tag:theconversation.com,2011:/uk/topics/flying-7131/articlesFlying – The Conversation2024-03-18T12:30:59Ztag:theconversation.com,2011:article/2228472024-03-18T12:30:59Z2024-03-18T12:30:59ZHow do airplanes fly? An aerospace engineer explains the physics of flight<figure><img src="https://images.theconversation.com/files/578175/original/file-20240227-28-cejldv.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C7668%2C4449&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">U.S. airlines carry more than 800 million passengers per year.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/airplane-isolated-on-sky-3d-rendering-royalty-free-image/1147868750?phrase=airplanes">Lasha Kilasonia/iStock via Getty Images Plus</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
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<p><strong>How do airplanes fly? – Benson, age 10, Rockford, Michigan</strong></p>
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<p>Airplane flight is one of the most significant technological achievements of the 20th century. The <a href="https://airandspace.si.edu/explore/stories/wright-brothers">invention of the airplane</a> allows people to travel from one side of the planet to the other in less than a day, compared with weeks of travel by boat and train.</p>
<p>Understanding precisely why airplanes fly is an ongoing challenge for <a href="https://www.clarkson.edu/people/craig-merrett">aerospace engineers, like me</a>, who study and design airplanes, rockets, satellites, helicopters and space capsules. </p>
<p>Our job is to make sure that flying through the air or in space is safe and reliable, by using tools and ideas from science and mathematics, like computer simulations and experiments. </p>
<p>Because of that work, flying in an airplane is <a href="https://usafacts.org/articles/is-flying-safer-than-driving/">the safest way to travel</a> – safer than cars, buses, trains or boats. But although aerospace engineers design aircraft that are stunningly sophisticated, you might be surprised to learn there are still some details about the physics of flight that we don’t fully understand.</p>
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<a href="https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram of an airplane that shows the four forces of flight." src="https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=381&fit=crop&dpr=1 600w, https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=381&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=381&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=479&fit=crop&dpr=1 754w, https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=479&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/577439/original/file-20240222-28-v3tjb4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=479&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The forces of weight, thrust, drag and lift act on a plane to keep it aloft and moving.</span>
<span class="attribution"><a class="source" href="https://www1.grc.nasa.gov/beginners-guide-to-aeronautics/airplane-cruise-balanced-forces/">NASA</a></span>
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<h2>May the force(s) be with you</h2>
<p>There are <a href="https://www.nasa.gov/stem-content/four-forces-of-flight/#:%7E">four forces</a> that aerospace engineers consider when designing an airplane: weight, thrust, drag and lift. Engineers use these forces to help design the shape of the airplane, the size of the wings, and figure out how many passengers the airplane can carry. </p>
<p>For example, when an airplane takes off, the thrust must be greater than the drag, and the lift must be greater than the weight. If you watch an airplane take off, you’ll see the wings change shape using flaps from the back of the wings. The flaps help make more lift, but they also make more drag, so a powerful engine is necessary to create more thrust. </p>
<p>When the airplane is high enough and is cruising to your destination, lift needs to balance the weight, and the thrust needs to balance the drag. So the pilot pulls the flaps in and can set the engine to produce less power.</p>
<p>That said, let’s define what force means. According to <a href="https://ca.pbslearningmedia.org/resource/4079abf0-7a4b-4f49-80ad-c69cd06a80f9/newtons-second-law-of-motion/">Newton’s Second Law</a>, a force is a mass multiplied by an acceleration, or F = ma. </p>
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<a href="https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black and white historical photograph of the first flight of the Wright brothers." src="https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=381&fit=crop&dpr=1 600w, https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=381&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=381&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=479&fit=crop&dpr=1 754w, https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=479&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/579678/original/file-20240304-22-jrh9mr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=479&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">On Dec. 17, 1903, the Wright brothers made their first flight at Kitty Hawk, N.C. Orville Wright is at the controls, while Wilbur looks on.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-flyer-takes-off-from-kill-devil-hill-with-orville-news-photo/517389284?adppopup=true">Bettmann via Getty Images</a></span>
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<p>A force that everyone encounters every day is <a href="https://spaceplace.nasa.gov/what-is-gravity/en/#:%7E">the force of gravity</a>, which keeps us on the ground. When you get weighed at the doctor’s office, they’re actually measuring the amount of force that your body applies to the scale. When your weight is given in pounds, that is a measure of force. </p>
<p>While an airplane is flying, gravity is pulling the airplane down. That force is the weight of the airplane. </p>
<p>But its engines push the airplane forward because they create <a href="https://www1.grc.nasa.gov/beginners-guide-to-aeronautics/what-is-thrust/">a force called thrust</a>. The engines pull in air, which has mass, and quickly push that air out of the back of the engine – so there’s a mass multiplied by an acceleration. </p>
<p>According to <a href="https://www.youtube.com/watch?v=a-wh3fJRdjo">Newton’s Third Law</a>, for every action there’s an equal and opposite reaction. When the air rushes out the back of the engines, there is a reaction force that pushes the airplane forward – that’s called thrust.</p>
<p>As the airplane flies through the air, the shape of the airplane pushes air out of the way. Again, by Newton’s Third Law, this air pushes back, <a href="https://www1.grc.nasa.gov/beginners-guide-to-aeronautics/what-is-drag/#:%7E">which leads to drag</a>. </p>
<p>You can experience something similar to drag when swimming. Paddle through a pool, and your arms and feet provide thrust. Stop paddling, and you will keep moving forward because you have mass, but you will slow down. The reason that you slow down is that the water is pushing back on you – that’s drag. </p>
<h2>Understanding lift</h2>
<p><a href="https://www1.grc.nasa.gov/beginners-guide-to-aeronautics/what-is-lift/">Lift</a> is more complicated than the other forces of weight, thrust and drag. It’s created by the wings of an airplane, and the shape of the wing is critical; that shape is <a href="https://howthingsfly.si.edu/media/airfoil#:%7E">known as an airfoil</a>. Basically it means the top and bottom of the wing are curved, although the shapes of the curves can be different from each other. </p>
<p>As air flows around the airfoil, <a href="https://www.youtube.com/watch?v=UO75jDwGCdQ">it creates pressure</a> – a force spread out over a large area. Lower pressure is created on the top of the airfoil compared to the pressure on the bottom. Or to look at it another way, air travels faster over the top of the airfoil than beneath. </p>
<p>Understanding why the pressure and speeds are different on the top and the bottom is <a href="https://airandspace.si.edu/multimedia-gallery/lift-and-copjpg">critical to understand lift</a>. By improving our understanding of lift, engineers can design more fuel-efficient airplanes and give passengers more comfortable flights.</p>
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<a href="https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram that shows how the airfoil of a plane works." src="https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/579698/original/file-20240304-24-6df49v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Note the airfoil, which is a specific wing shape that helps keep a plane in the air.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/how-airplanes-fly-royalty-free-illustration/1401215523?phrase=airfoil+diagram&adppopup=true">Dimitrios Karamitros/iStock via Getty Images Plus</a></span>
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<h2>The conundrum</h2>
<p>The reason why air moves at different speeds around an airfoil remains mysterious, and <a href="https://www.scientificamerican.com/video/no-one-can-explain-why-planes-stay-in-the-air/">scientists are still investigating</a> this question. </p>
<p>Aerospace engineers have measured these pressures on a wing in both wind tunnel experiments and during flight. We can create models of different wings to predict if they will fly well. We can also change lift by changing a wing’s shape to create airplanes that fly for long distances or fly very fast. </p>
<p>Even though we still don’t fully know why lift happens, aerospace engineers work with mathematical equations that recreate the different speeds on the top and bottom of the airfoil. Those equations describe a process <a href="https://howthingsfly.si.edu/media/circulation-theory-lift">known as circulation</a>. </p>
<p>Circulation provides aerospace engineers with a way to model what happens around a wing even if we do not completely understand why it happens. In other words, through the use of math and science, we are able to build airplanes that are safe and efficient, even if we don’t completely understand the process behind why it works.</p>
<p>Ultimately, if aerospace engineers can figure out why the air flows at different speeds depending on which side of the wing it’s on, we can design airplanes that use less fuel and pollute less.</p>
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<p class="fine-print"><em><span>Craig Merrett receives funding from the Office of Naval Research and L3Harris. He is affiliated with the American Institute for Aeronautics and Astronautics, and is a licensed professional engineering in Ontario, Canada. Dr. Merrett is an associate professor in the Department of Mechanical and Aerospace Engineering at Clarkson University, Potsdam, NY. </span></em></p>People have been flying airplanes for well over a century. Engineers know how to balance all the forces at play, but still aren’t exactly sure how some of the physics of flight actually works.Craig Merrett, Professor of Mechanical and Aerospace Engineering, Clarkson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2217802024-01-24T17:39:08Z2024-01-24T17:39:08ZHere’s what happens to your body during plane turbulence – and how to reduce the discomfort it causes<figure><img src="https://images.theconversation.com/files/570863/original/file-20240123-19-j98p69.jpg?ixlib=rb-1.1.0&rect=0%2C12%2C8179%2C5444&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-firmly-holds-mans-hand-during-1806710980">H Ko/Shutterstock</a></span></figcaption></figure><p>This week has seen another barrage of <a href="https://www.theguardian.com/uk-news/2024/jan/22/uk-weather-storm-jocelyn-to-follow-isha-with-more-strong-winds-and-heavy-rain">unsettled weather</a> sweep across the UK, with many flights delayed or cancelled. Some of those who were fortunate enough to take off found themselves arriving at destinations that weren’t on their boarding passes – such as passengers travelling from Stansted to Newquay who eventually diverted to <a href="https://uk.news.yahoo.com/storm-isha-creates-flight-diversion-142821278.html?">Malaga</a>.</p>
<p>One thing that was consistently described by passengers was that parts of the flights and the attempted landings were some of the most unnerving they’d ever experienced, due to turbulence.</p>
<p>Turbulence results from uneven air movement, which is <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023GL103814">increasing</a> in frequency. If you turn your hair dryer on at home and hold it still, the air moves at a constant rate, but once you begin drying your hair and moving the hairdryer around, the air movement becomes uneven, that is to say, turbulent.</p>
<p>Although turbulence may be unnerving and make you feel unwell, it is important to recognise that it is very common and typically <a href="https://pubmed.ncbi.nlm.nih.gov/18018437/">nothing to worry about</a> if you’re in your seat with your seatbelt fastened.</p>
<h2>How the body detects and responds to turbulence</h2>
<p>The body recognises itself within any environment. Its relationship with objects in terms of distance and direction is called <a href="https://www.sciencedirect.com/science/article/abs/pii/B9780123750006003414">spatial orientation</a>. </p>
<p>When flying, this is typically moving forwards, ascending, some turns and a descent. However, turbulence disrupts this relationship and confuses the sensory information being received by the brain – it makes the body want to respond or recalibrate.</p>
<p>Our inner ears play a pivotal role in all this. It consists of complex apparatuses that undertake more than hearing. These include the cochlea, <a href="https://www.ncbi.nlm.nih.gov/books/NBK279394/">three semi-circular canals</a>, <a href="https://radiopaedia.org/articles/utricle-ear?lang=gb">the utricle</a> and <a href="https://radiopaedia.org/articles/saccule-ear-1?lang=gb">the saccule</a>. </p>
<p>The cochlea is responsible for hearing. It converts <a href="https://www.ncbi.nlm.nih.gov/books/NBK531483/">sound energy into electrical energy</a> that is then “heard” by the brain. The remaining structures are responsible for the balance and position of the head and body. The semi-circular canals are positioned in a vertical (side to side), horizontal and front-to-back plane, detecting movement in a nodding, shaking and touching ear-to-shoulder direction. </p>
<p>Attached to these canals are <a href="https://www.ncbi.nlm.nih.gov/books/NBK532978/">the utricle and saccule</a>, which can detect <a href="https://www.ncbi.nlm.nih.gov/books/NBK10792/">movement</a> and <a href="https://www.cell.com/current-biology/pdf/S0960-9822(05)00837-7.pdf">acceleration</a>. </p>
<p>All of these apparatuses use microscopic hair cells in a specialised fluid called <a href="https://www.ncbi.nlm.nih.gov/books/NBK531505/">endolymph</a> that flows with the head to create a sense of movement. When the plane encounters turbulence, this fluid moves around, but unpredictably. It takes <a href="https://www.ncbi.nlm.nih.gov/books/NBK518976/">about ten to 20 seconds</a> for the fluid to recalibrate its position, while the brain struggles to understand what is going on.</p>
<p>When the aircraft hits turbulence, the balance apparatus <a href="https://www.frontiersin.org/articles/10.3389/fneur.2023.949227/full">cannot distinguish</a> the movement of the plane from that of the head, so the brain interprets the aircraft movement as that of the head or body. But this doesn’t match the visual information being received, which causes sensory confusion.</p>
<p>The reason the inner ear causes so much confusion is because during flights you are devoid of your primary sensory tool relative to the external environment – your sight and the horizon. </p>
<p>Eighty per cent of <a href="https://www.ncbi.nlm.nih.gov/books/NBK518976/">spatial information</a> comes from your eyes during flight. However, you only have the seat in front of you or the cabin as a reference point, which means your inner ear becomes the dominant sensory message to the brain during turbulence and disrupts the <a href="https://www.ncbi.nlm.nih.gov/books/NBK545297/">“vestibulo-ocular reflex”</a>. This reflex keeps your vision <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4130651/">aligned</a> with your balance or expected position. </p>
<p>Vision is the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6777262/">most valued</a> of the senses and one-third of the brain is attributed to its function, reinforcing its importance in spatial orientation.</p>
<p>This sensory mixed messaging often results in things like dizziness and sweating as well as gastrointestinal symptoms, such as <a href="https://www.airmedicaljournal.com/article/S1067-991X(02)70038-2/fulltext">nausea and vomiting</a>. </p>
<p>Motion sickness can be triggered by turbulence and although research into specific airsickness is limited, other modes that induce motion sickness suggest that <a href="https://pubmed.ncbi.nlm.nih.gov/16018346/">women</a> are <a href="https://pubmed.ncbi.nlm.nih.gov/26466829/">more susceptible</a> than men, particularly in the <a href="https://pubmed.ncbi.nlm.nih.gov/16235881/">early stages</a> of the menstrual cycle. </p>
<p>The turbulence also causes an increase in your heart rate, which is already higher than normal when flying because of a <a href="https://pubmed.ncbi.nlm.nih.gov/15819766/">decrease in oxygen saturation</a>.</p>
<h2>What about the pilots?</h2>
<p>Commercial pilots accrue thousands of hours at the controls, they are subject to the same forces as the passengers. </p>
<p>Over time, they can <a href="https://academic.oup.com/milmed/article/180/11/1135/4160573">adapt to these forces</a> and <a href="https://pubmed.ncbi.nlm.nih.gov/15828634/">experiences</a>, but they also have a couple of additional resources that most passengers don’t. </p>
<p>They have the view out of the cockpit windows, so have a horizon to use as a reference point and can see what lies immediately ahead. </p>
<p>If it is cloudy or visibility is low, their instruments provide additional visual <a href="https://www.faa.gov/sites/faa.gov/files/regulations_policies/handbooks_manuals/aviation/phak/19_phak_ch17.pdf">reference</a> to the position of the aircraft. This doesn’t mean they are immune to the effects of turbulence, with some studies reporting up to <a href="https://pubmed.ncbi.nlm.nih.gov/26540704/">71% of trainee pilots</a> reporting episodes of airsickness.</p>
<h2>How to reduce the discomfort</h2>
<p>A window seat can help, or even looking out the window. This gives the brain some sensory information through visual pathways, helping calm the brain in response to the vestibular information it is receiving.</p>
<p>If you can get one, a seat towards the front or over the wing reduces the effects of turbulence.</p>
<p>Deep or rhythmical breathing can help reduce motion sickness induced by turbulence. Focusing on your breathing <a href="https://pubmed.ncbi.nlm.nih.gov/25945662/">calms the nervous system</a>.</p>
<p>Don’t reach for the alcohol. While you may feel it calms your nerves, if you hit turbulence it’s going to interfere with your <a href="https://pubmed.ncbi.nlm.nih.gov/7610847/">visual and auditory processing</a> and increase the likelihood of vomiting.</p>
<p>If you suffer from motion sickness and are worried about turbulence while flying, then there are also <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6241144/">drugs that can help</a>, including certain <a href="https://www.nhs.uk/medicines/cinnarizine/about-cinnarizine/">antihistamines</a>. </p>
<p>Finally, it’s important to remember that although turbulence can be unpleasant, aircraft are designed to withstand the forces it generates and many passengers, even frequent fliers, will rarely encounter the most severe categories of turbulence because pilots actively plan routes to avoid it.</p><img src="https://counter.theconversation.com/content/221780/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adam Taylor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>An anatomist explains why turbulence on flights makes us feel so ill and disoriented.Adam Taylor, Professor and Director of the Clinical Anatomy Learning Centre, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2185442023-11-28T09:30:31Z2023-11-28T09:30:31ZWhy the world’s first flight powered entirely by sustainable aviation fuel is a green mirage<figure><img src="https://images.theconversation.com/files/561822/original/file-20231127-21-kn1l9m.jpg?ixlib=rb-1.1.0&rect=0%2C15%2C4516%2C3366&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Boeing 787 Dreamliner landing at Heathrow international airport in London.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/heathrow-london-united-kingdom-july-13-726338329">Fasttailwind/Shutterstock</a></span></figcaption></figure><p>A Boeing 787 Dreamliner is set to take off from Heathrow on November 28 and head for JFK airport in New York, powered by so-called sustainable aviation fuel (SAF). According to its operator, Virgin Atlantic, the world’s “first 100% SAF flight” <a href="https://www.virgin.com/about-virgin/latest/virgin-atlantics-historic-net-zero-transatlantic-flight-closer-to-takeoff">will mark</a> “a historic moment in aviation’s roadmap to decarbonisation”.</p>
<p>It is proof of concept, we are led to believe, of the dawn of <a href="https://twitter.com/grantshapps/status/1616329685251620864?lang=en">“guilt-free” flying</a>. Unfortunately, we have been here before, and the results last time were anything but green. </p>
<p>Based on <a href="https://theecologist.org/2021/aug/27/jet-zero-and-politics-technofix">our research</a> into how wealth and power shape the environment, we argue that continued growth of the aviation sector, as with the economy in general, is incompatible with preventing runaway climate change. The technology currently being developed by the aviation industry has zero chance of changing that. And the fuels being used in Virgin’s latest experiment are not significantly more sustainable than those in its previous attempt.</p>
<p>Virgin’s sustainability initiative dates back to the 2000s, when British business magnate Richard Branson was at the helm. In 2008, to some fanfare, a Virgin aircraft flew from <a href="https://www.inderscienceonline.com/doi/abs/10.1504/IJMCP.2008.021271">London to Amsterdam</a> using a fuel derived in part from palm oil and coconuts. Technically, the mission was a success, but the sustainability claims were laughable. </p>
<p>To have fuelled that short hop with 100% coconut oil would have consumed <a href="https://www.inderscienceonline.com/doi/abs/10.1504/IJMCP.2008.021271">3 million coconuts</a>. The entire global crop would supply Heathrow for only a few weeks — and it is one of 18,000 commercial airports worldwide. Following this stunt, Virgin gave up on coconut oil.</p>
<p>Virgin’s latest flight is simply a repeat of 2008. It’s a smoke-and-mirrors exercise to convince governments that SAF will enable aviation to continue its relentless growth on a sustainable basis – and in this, it is succeeding.</p>
<h2>Even waste products aren’t sustainable</h2>
<p>Virgin’s defence rests on the claim that its new SAF no longer comes exclusively from crops. It is blended with waste products. One of the main suppliers for Virgin’s transatlantic flight is Virent, an organisation based in Wisconsin. Virent makes SAF from conventional sugars such as corn, mixed with wood, agricultural waste and used cooking oil. </p>
<p>As with coconuts, any crop grown for fuel competes with foodstuffs and pushes the agricultural frontier further into forests and peatlands, with large releases of carbon.</p>
<p>But what of the waste products? Surely reusing cooking oils offers a sustainable solution? Unfortunately, in a notoriously unregulated market, it seems not. </p>
<p>Another of Virgin’s suppliers, Neste, collects cooking oils from sources worldwide, including <a href="https://journeytozerostories.neste.com/circular-economy/fries-miles-circularity-partnership">McDonald’s</a> restaurants in the Netherlands and <a href="https://www.neste.com/releases-and-news/circular-economy/nestes-acquisition-used-cooking-oil-collection-and-aggregation-business-crimson-renewable-energy">food processing plants</a> in California, Oregon and Washington. The US Department of Agriculture alleges that some trade in SAF feedstocks – including from Indonesia to Neste’s refinery in Singapore – may be “<a href="https://apps.fas.usda.gov/newgainapi/api/Report/DownloadReportByFileName?fileName=Biofuels%20Annual_Beijing_China%20-%20People%27s%20Republic%20of_CH2023-0109.pdf">fraudulent</a>”. </p>
<p>Neste has <a href="https://biofuels-news.com/news/neste-rejects-usda-claims-it-received-fraudulent-uco-volumes/">denied</a> the claim. But, even if its used cooking oil is entirely legitimate, there is still an allegation that palm oil from plantations responsible for tropical deforestation is <a href="https://www.opendemocracy.net/en/uk-airlines-sustainable-fuel-used-cooking-oil-deforestation-palm-oil/">being marketed as used cooking oil</a>. </p>
<p>Virgin Atlantic maintains that the SAF it uses is made entirely from used cooking oil. However, if the aviation industry bets big on used cooking oil, it is feared it will <a href="https://en.milieudefensie.nl/news/02097-opm-rapport-neste-21.pdf">turbocharge tropical logging</a> and the extermination of the orangutan and countless other endangered species.</p>
<figure class="align-center ">
<img alt="Orangutan in the rainforest on Borneo island with trees and palms behind." src="https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=416&fit=crop&dpr=1 600w, https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=416&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=416&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=522&fit=crop&dpr=1 754w, https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=522&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/561825/original/file-20231127-15-6glkuc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=522&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">More tropical logging would threaten the orangutan and countless other endangered species.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/orangutan-his-natural-environment-rainforest-on-1686141565">Michail_Vorobyev/Shutterstock</a></span>
</figcaption>
</figure>
<p>The real kicker is that even if all used cooking oils were traceable and sustainably sourced, they are <a href="https://theicct.org/sites/default/files/publications/Sustainable-aviation-fuel-feedstock-eu-mar2021.pdf">not scalable</a>. The US collects around <a href="https://www.researchgate.net/publication/344753554_Comparative_study_of_properties_and_fatty_acid_composition_of_some_neat_vegetable_oils_and_waste_cooking_oils">600,000 tonnes</a> of used cooking oil each year. If every last drop were diverted to SAFs, it would meet at most 1% of America’s current aviation demand. </p>
<h2>Capturing the White House</h2>
<p>The problems of scalability, the competition of agricultural inputs with foodstuffs, forests and wildlife, and the <a href="https://www.reuters.com/business/environment/us-corn-based-ethanol-worse-climate-than-gasoline-study-finds-2022-02-14/">carbon emissions</a> that result from <a href="https://grain.org/article/entries/4653-land-grabbing-for-biofuels-must-stop#6">land use change</a> are just three of the shortcomings that ensure SAFs will not be the magic bullet that the aviation industry would have us believe. Despite this, SAF fever has won over the White House. </p>
<p>The Inflation Reduction Act set targets for SAF production at 3 billion gallons by 2030 and <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2021/09/09/fact-sheet-biden-administration-advances-the-future-of-sustainable-fuels-in-american-aviation/">35 billion by 2050</a>. These targets are fantasies. But, to the extent that they are approached, they will only add to the pressure on food prices and wildlife.</p>
<p>That SAF is being touted so zealously attests to the shortage of <a href="https://www.noemamag.com/the-seductive-vision-of-green-aviation/">alternative technologies</a>. Battery-powered planes are viable but only as short-haul <a href="https://www.theguardian.com/world/2023/jun/24/your-electric-flying-taxi-is-just-around-the-corner">“flying taxis”</a> that compete with ground transport. The other panacea, <a href="https://stay-grounded.org/wp-content/uploads/2021/08/SG_factsheet_8-21_Hydrogen_FIN_Korr.pdf">hydrogen</a>, confronts colossal technological and infrastructural barriers, problems of scalability, competing uses, and <a href="https://theconversation.com/green-hydrogen-why-low-carbon-fuels-are-not-benefiting-from-high-fossil-fuel-prices-195774">environmental concerns</a>. </p>
<p>Tinkering with aircraft technology, such as engine size or wing shape has also faced <a href="https://theecologist.org/2021/aug/27/jet-zero-and-politics-technofix">diminishing returns</a>. Efficiency improvements lag far behind the sector’s growth, which is why aviation emissions are still soaring.</p>
<h2>Where do we go from here?</h2>
<p>Ahead of the 2008 coconut-fuelled flight, Virgin’s chief executive <a href="https://www.telegraph.co.uk/news/earth/earthnews/3291122/Virgin-plans-biofuel-aeroplanes.html">Steve Ridgway</a> explained its logic. He said the aviation industry needs “to be seen to be doing something”. Fifteen years on and the playbook remains the same. </p>
<p>The Virgin Atlantic SAF flight promises to rescue the airline from the threat of climate change, allowing them and their passengers to “keep calm and carry on”. In buying into this fantasy, governments give themselves an excuse to avoid taking climate breakdown seriously – an emergency that requires radical action if the planet is to remain habitable for humans.</p>
<p>There is the potential to create a <a href="https://theconversation.com/is-it-possible-for-everyone-to-live-a-good-life-within-our-planets-limits-91421">good life for all within planetary boundaries</a>. But getting there requires clipping the wings of the aviation industry. </p>
<p>This would begin, for short-haul, with ground-based alternatives. Within the US, many flights could be swiftly replaced by coach travel, and <a href="https://theicct.org/aviation-rail-shift-lower-carbon-mar22/">over a quarter</a> of flights between EU destinations could be replaced by high-speed rail. For long-haul, the first step is <a href="https://theecologist.org/2021/aug/31/jet-zero-one-way-ticket-climate-hell">demand management</a>, which will expedite the use of virtual conferencing, marine transportation and other alternatives.</p>
<figure class="align-center ">
<img alt="Modern high-speed train driving past a station in a city." src="https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/561828/original/file-20231127-15-f776rj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Many flights could be replaced by high-speed rail.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/modern-high-speed-electric-passenger-driving-1229706781">aappp/Shutterstock</a></span>
</figcaption>
</figure>
<p>Developing alternatives would be <a href="https://www.bbc.com/future/article/20220519-what-if-we-all-stopped-flying">practical, efficient and create jobs</a>. And now is a good time to begin. Americans have been “<a href="https://www.ft.com/content/4341f119-09e4-4644-ab6f-fac585040358">falling out of love with flying</a>” in recent years, in part due to large numbers of flight cancellations following bad weather, which is only likely to increase with climate breakdown. </p>
<p>As the weather chaos worsens, the aviation industry will find it harder to shrug off its responsibility through PR stunts and greenwashed gimmickry.</p>
<p><em>In response to this article, a Virgin Atlantic spokesperson said that the organisation is committed to achieving net zero by 2050, and has set interim targets, including 10% SAF by 2030. It sees SAF as a mid-term solution for decarbonising aviation, and that Flight100 aims to demonstrate the safe use of 100% SAF within existing infrastructure. Virgin Atlantic referred to a Sustainable Aviation report, which indicates that there is sufficient feedstock to meet the government’s 2030 target without environmental impact or competition with crop production.</em></p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A flight powered by sustainable aviation fuel is making a trip across the Atlantic. But is it really a greener way to fly?Gareth Dale, Reader in Political Economy, Brunel University LondonJosh Moos, Lecturer in Economics and Politics, Leeds Beckett UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2180372023-11-28T03:49:33Z2023-11-28T03:49:33ZAlmost half the men surveyed think they could land a passenger plane. Experts disagree<figure><img src="https://images.theconversation.com/files/561998/original/file-20231127-29-h9xkjy.jpg?ixlib=rb-1.1.0&rect=69%2C0%2C5754%2C3877&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Picture this: you’re nestled comfortably in your seat cruising towards your holiday destination when a flight attendant’s voice breaks through the silence: </p>
<blockquote>
<p>Ladies and gentlemen, both pilots are incapacitated. Are there any passengers who could land this plane with assistance from air traffic control?</p>
</blockquote>
<p>If you think you could manage it, you’re not alone. <a href="https://today.yougov.com/topics/politics/survey-results/daily/2023/01/02/fd798/3">Survey results</a> published in January indicate about one-third of adult Americans think they could safely land a passenger aircraft with air traffic control’s guidance. Among male respondents, the confidence level rose to nearly 50%.</p>
<p>Can a person with no prior training simply guide everyone to a smooth touchdown?</p>
<p>We’ve all heard stories of passengers who saved the day when the pilot became unresponsive. For instance, last year <a href="https://www.youtube.com/watch?v=qbMoyWukjbs">Darren Harrison</a> managed to land a twin-engine aircraft in Florida – after the pilot passed out – with the guidance of an air traffic controller who also happened to be a flight instructor. </p>
<p>However, such incidents tend to take place in small, simple aircraft. Flying a much bigger and heavier commercial jet is a completely different game. </p>
<h2>You can’t always rely on autopilot</h2>
<p>A pilot spends about 90% of their time monitoring autopilot systems and making sure everything is working as intended. The other 10% is spent managing problems, taxiing, taking off and landing. </p>
<p>Takeoffs and landings are arguably the most difficult tasks pilots perform, and are always performed manually. Only on very few occasions, and in a handful of aircraft models, can a pilot use autopilot to land the aircraft for them. This is the exception, and not the rule.</p>
<p>For takeoff, the aircraft must build up speed until the wings can generate enough lift to pull it into the air. The pilot must <a href="https://youtu.be/16XTAK-4Xbk?si=66yDo5g5I086Q2y2&t=65">pay close attention</a> to multiple instruments and external cues, while keeping the aircraft centred on the runway until it reaches lift-off speed. </p>
<p>Once airborne, they must coordinate with air traffic control, follow a particular path, retract the landing gear and maintain a precise speed and direction while trying to climb. </p>
<p>Landing is even more complicated, and requires having precise control of the aircraft’s direction and descent rate.</p>
<p><a href="https://youtu.be/u_it9OiTnSM?si=xNZrLB9ZH870LEa3&t=360">To land successfully</a>, a pilot must keep an appropriate speed while simultaneously managing gear and flap configuration, adhering to air traffic regulations, communicating with air traffic control and completing a number of paper and digital checklists.</p>
<p>Once the aircraft comes close to the runway, they must accurately judge its height, reduce power and adjust the rate of descent – ensuring they land on the correct area of the runway.</p>
<p>On the ground, they will use the brakes and reverse thrust to bring the aircraft to a complete stop before the runway ends. This all happens within just a few minutes. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Nyx4NyMrvOs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>Both takeoff and landing are far too quick, technical and concentration-intensive for an untrained person to pull off. They also require a range of skills that are only gained through extensive training, such as understanding the information presented on different gauges, and being able to coordinate one’s hands and feet in a certain way.</p>
<h2>Training a pilot</h2>
<p>The journey from student to commercial pilot is a long one. It normally starts with a recreational licence, followed by a private licence, and then a commercial licence (which allows them to fly professionally). </p>
<p>Even before stepping into a cockpit, the student must study aerodynamics, air law and flight rules, meteorology, human factors, navigation, aircraft systems, and performance and flight planning. They also need to spend time learning about the specific aircraft they will be flying. </p>
<p>Once the fundamentals are grasped, an instructor takes them for training. Most of this training is conducted in small, lightweight aircraft – with a simulator introduced briefly towards the end.</p>
<p>During a lesson, each manoeuvre or action is demonstrated by the instructor before the student attempts it. Their attempt may be adjusted, corrected or even terminated early in critical situations.</p>
<p>The first ten to fifteen lessons focus on takeoff, landing, basic in-flight control and emergency management. When the students are ready, they’re allowed to “go solo” – wherein they conduct a complete flight on their own. This is a great milestone.</p>
<p>After years of experience, they are ready to transition to a commercial aircraft. At this point they might be able to take off and land reasonably well, but they will still undergo extensive training specific to the aircraft they are flying, including hours of advanced theory, dozens of simulator sessions and hundreds of hours of real aircraft training (most of which is done with passengers onboard).</p>
<p>So, if you’ve never even learned the basics of flying, your chances of successfully landing a passenger aircraft with air traffic control’s help are close to zero.</p>
<h2>Yet, flying is a skill like any other</h2>
<p>Aviation training has been democratised by the advent of high-end computers, virtual reality and flight simulation games such as Microsoft’s <a href="https://www.flightsimulator.com/">Flight Simulator</a> and <a href="https://www.x-plane.com/">X-Plane</a>.</p>
<p>Anyone can now rig up a desktop flight simulator for a few thousand dollars. Ideally, such a setup should also include the basic physical controls found in a cockpit, such as a control yoke, throttle quadrant and pedals. </p>
<p>Flight simulators provide an immersive environment in which professional pilots, students and aviation enthusiasts can develop their skills. So if you really think you could match-up against a professional, consider trying your hand at one. </p>
<p>You almost certainly won’t be able to land an actual passenger plane by the end of it – but at least you’ll gain an appreciation for the immense skill pilots possess.</p><img src="https://counter.theconversation.com/content/218037/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>We conducted a research project with funds provided by Boeing Research & Technology Australia.</span></em></p>Takeoff and landing are among the most difficult tasks commercial pilots perform.Guido Carim Junior, Senior Lecturer in Aviation, Griffith UniversityChris Campbell, Adjunct Associate Professor, Griffith UniversityElvira Marques, Aviation PhD candidate, Griffith UniversityNnenna Ike, Research Assistant, Griffith Aviation, Griffith UniversityTim Ryley, Professor and Head of Griffith Aviation, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2172312023-11-20T14:37:27Z2023-11-20T14:37:27ZAirlines are frustrating travelers by changing frequent flyer program rules – here’s why they keep doing it<figure><img src="https://images.theconversation.com/files/558086/original/file-20231107-267500-6jwx0k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A boom time for airlines can a bust for loyal passengers.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/friends-at-the-international-airport-in-barcelona-royalty-free-image/1009031554">Martin-dm/E+/Getty Images</a></span></figcaption></figure><p>As the U.S. <a href="https://theconversation.com/us/topics/holiday-travel-47493">holiday travel season</a> picks up, many people are noticing that their frequent flyer benefits aren’t going as far as they used to. </p>
<p>In September 2023, <a href="https://www.wsj.com/business/airlines/delta-loyalty-program-changes-reward-biggest-spenders-most-dcefa85e">Delta Air Lines revamped its frequent flyer program</a> to make it tougher to earn status — a tiered system offering travel privileges based on the reward points earned — only to partially <a href="https://www.wsj.com/business/airlines/delta-air-lines-makes-changes-to-its-skymiles-loyalty-programagain-b66519e6">reverse course</a> a month later and make it easier. American Airlines also made <a href="https://news.aa.com/news/news-details/2022/American-Airlines-to-Offer-AAdvantage-Members-More-Rewards-More-Often-Before-and-Beyond-Reaching-Status-AADV-12/default.aspx">big changes to its loyalty scheme in 2022</a> and <a href="https://www.foxbusiness.com/lifestyle/american-airlines-adjusts-loyalty-program-switches-to-dynamic-pricing">minor changes in spring 2023</a>. And British Airways recently announced that it is <a href="https://www.britishairways.com/en-us/executive-club/faqs/collecting-avios-changes">adjusting the way it awards points for travel</a>.</p>
<p><a href="https://www.bu.edu/questrom/profile/huseyin-karaca/">We are</a> <a href="https://www.bu.edu/questrom/">business school</a> <a href="https://www.bu.edu/questrom/profile/jay-zagorsky/">professors</a> who study <a href="https://theconversation.com/whens-the-best-time-to-use-frequent-flyer-miles-to-book-flights-two-economists-crunched-the-numbers-on-maximizing-their-dollar-value-194893">rewards</a> <a href="https://theconversation.com/starbucks-fans-are-steamed-the-psychology-behind-why-changes-to-a-rewards-program-are-stirring-up-anger-even-though-many-will-get-grande-benefits-198361">programs</a>. Many people think <a href="https://www.theguardian.com/us-news/2023/jun/12/us-air-travel-workers-passengers">flying is a miserable experience</a>, and having status sometimes makes flights better. So it’s only fair that frequent flyers are asking why it’s seemingly harder to obtain such status.</p>
<h2>Why miles are a multibillion-dollar business</h2>
<p>One big idea to understand is that <a href="https://www.mckinsey.com/industries/travel-logistics-and-infrastructure/our-insights/the-six-secrets-of-profitable-airlines">airlines don’t earn very much money</a>, if any at all, from ticket sales. This is mainly due to the highly competitive and capital-intensive structure of the airline industry, which often leads to reduced profit margins. Instead, they make their profits from <a href="https://www.bts.gov/topics/airlines-and-airports/baggage-fees-airline-2022">bag fees</a>, <a href="https://www.bts.gov/cancellation-change-fees">ticket change fees</a> and — importantly — <a href="https://www.transportation.gov/individuals/aviation-consumer-protection/frequent-flyer-programs">frequent flyer</a> programs. </p>
<p>On many airlines, there are two ways to earn status. <a href="https://www.washingtonpost.com/opinions/2023/06/23/united-airlines-very-frequent-flyer">One is to fly a lot</a>. But that means spending time in crowded airports. The other way is to <a href="https://www.delta.com/us/en/skymiles/medallion-program/2024-program-updates">spend a lot of money using a rewards credit card</a>.</p>
<p>Frequent flyer programs, coupled with rewards credit cards, are very profitable for airlines. For example, Delta’s <a href="https://s2.q4cdn.com/181345880/files/doc_downloads/2023/02/DAL-12.31.2022-10K-2.10.23.pdf">latest annual report</a> shows last year that the company earned US$5.7 billion from selling credit card miles. Given Delta only made $3.6 billion in profits, this frequent flyer program clearly boosts the bottom line.</p>
<h2>Designing the optimal rewards program</h2>
<p>Many types of businesses, not just airlines, offer <a href="https://www.starbucks.com/rewards">rewards programs</a>. From a company’s perspective, a <a href="https://knowledge.insead.edu/operations/optimal-design-loyalty-programmes">well-designed loyalty program</a> should cost little or nothing, give customers great value and prevent them from using a competitor. </p>
<p>Frequent flyer programs fit this bill: Giving some passengers the ability to board early or access to a lounge costs airlines almost nothing, but many customers desire it. Plus, the chase for status or free flights <a href="https://hbr.org/1995/05/do-rewards-really-create-loyalty">locks people</a> into using only one airline.</p>
<p>Much of the appeal of status programs comes from their exclusivity. This leaves airlines with a problem: where to set the bar. A low bar means nearly everyone gains status. But customers <a href="https://nymag.com/intelligencer/2019/05/heres-why-airplane-boarding-got-so-ridiculous.html">get no value</a> being allowed to board first if almost everyone on the plane can also do it, and <a href="https://www.marketwatch.com/story/why-are-clubs-so-crowded-these-days-airport-lounges-have-lost-their-peaceful-privilege-are-they-worth-it-anymore-54572642">airport lounges aren’t a haven</a> when travelers can’t find empty seats. At the same time, setting the bar too high results in empty lounges and unhappy customers.</p>
<p>Striking the right balance is tough, since the number of flyers is constantly changing due to <a href="http://businessmacroeconomics.com/">economic conditions</a>. When the economy is doing well, <a href="https://www.trade.gov/national-travel-and-tourism-office">people want to travel</a>. This gives airlines an incentive to tighten frequent flyer rules. When the economy is doing poorly, people stay home and airlines relax their rules.</p>
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<figcaption><span class="caption">Delta’s CEO discusses the backlash to recent loyalty program changes on Bloomberg Television on Oct. 25, 2023.</span></figcaption>
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<p>For example, at the height of the COVID-19 pandemic, <a href="https://www.mckinsey.com/industries/travel-logistics-and-infrastructure/our-insights/taking-stock-of-the-pandemics-impact-on-global-aviation">few people flew</a>, so <a href="https://www.nytimes.com/2021/11/05/travel/airline-loyalty-programs.html">airlines made it easy to earn</a> or keep status. Today, with the economy doing better and flying back to pre-pandemic levels, airlines are making it much tougher.</p>
<p>Many airlines are switching from a frequent flyer status model based on miles traveled to one based on dollars spent. This move aligns with the main design principle of these programs: The benefits a company gives to customers must mirror the value it gets from them.</p>
<h2>Who pays for all those rewards, anyway?</h2>
<p>Rewards programs are very profitable for airlines and their credit card partners. But for cardholders, the value proposition is less clear. These cards promise “free” rewards, but don’t actually deliver anything for free.</p>
<p>First, rewards cards often come with an annual fee. <a href="https://www.forbes.com/advisor/credit-cards/best/airline/">Fees typically range</a> from around $100 per year for a simple airlines reward card to $600 for a card that gives lounge access. Second, since many people don’t pay off their credit card balance each month, these card companies <a href="https://www.consumerfinance.gov/about-us/blog/americans-pay-120-billion-in-credit-card-interest-and-fees-each-year/">make billions of dollars charging</a> people interest.</p>
<p>Credit card companies also charge merchants roughly 2.5% every time a customer swipes a reward card — what’s known as <a href="https://www.usatoday.com/money/blueprint/business/credit-card-processing/interchange-fee/">the interchange fee</a>. The more generous the card, the higher the fee merchants have to pay. In general, when sellers encounter many consumers using reward cards, they <a href="https://luluywang.github.io/PaperRepository/payment_jmp.pdf">raise prices to offset the additional cost</a>.</p>
<p>What do all these fees mean for the typical flyer? People who pay off their reward card balances in full every month get roughly back the extra amount they pay in fees and charges. People who don’t pay off their balances, or who use debit cards or cash, pay more so that reward card holders get “free” travel. The result is that poorer and less financially savvy people <a href="https://www.cnbc.com/2023/05/27/lower-income-americans-pay-for-wealthys-credit-card-rewards-some-economists-say.html">end up subsidizing</a> the flights of richer people.</p>
<h2>A boom time for airlines, less so for passengers</h2>
<p>Since the deregulation of air travel in the 1970s, airlines have <a href="https://www.faa.gov/sites/faa.gov/files/2022-06/Forecast_Highlights.pdf">gone through boom and bust cycles</a>. Right now, it’s a boom for airlines and a bust for people looking for frequent flyer status. There’s no reason for airlines to be as rewarding today as they were in the past. <a href="https://theconversation.com/passport-bottleneck-is-holding-up-international-travel-by-americans-eager-to-see-the-world-as-covid-19-eases-205271">Planes are full</a> of people willing to pay with money. Sometime in the future, however, it will reverse, and it will be a boom time for flyers looking for status when planes begin having empty capacity.</p>
<p>In the meantime, what should you do? Our general advice is that if you are going to use a reward card, choose a card that gives cash back, not one that gives airplane miles. Good old cash is far more useful than miles. <a href="https://www.forbes.com/advisor/credit-cards/travel-rewards/how-to-protect-points/">Miles can be devalued</a> by an airline at any moment. Plus, even the most elite status doesn’t help much when <a href="https://public.tableau.com/app/profile/flightaware/viz/AirlineCancellationDelayUpdate/USAirlineCancellationsDelays">your plane is delayed</a> — and that’s happening more and more these days.</p><img src="https://counter.theconversation.com/content/217231/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Loyalty schemes tend to be the most generous when the economy has hit a patch of turbulence.Jay L. Zagorsky, Clinical Associate Professor of Markets, Public Policy and Law, Boston UniversityH. Sami Karaca, Professor of Business Analytics, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2165032023-11-03T17:29:56Z2023-11-03T17:29:56ZIt’s time to limit how often we can travel abroad – ‘carbon passports’ may be the answer<figure><img src="https://images.theconversation.com/files/556887/original/file-20231031-15-1auro3.jpg?ixlib=rb-1.1.0&rect=64%2C0%2C7128%2C4748&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-carries-luggage-airport-terminal-403443151">Shine Nucha/Shutterstock</a></span></figcaption></figure><p>The summer of 2023 has been very significant for the travel industry. By the end of July, international tourist arrivals globally <a href="https://www.unwto.org/news/international-tourism-swiftly-overcoming-pandemic-downturn">reached 84% of pre-pandemic levels</a>. In <a href="https://joint-research-centre.ec.europa.eu/jrc-news-and-updates/eu-tourism-almost-full-recovery-pre-pandemic-levels-2023-10-23_en">some European countries</a>, such as France, Denmark and Ireland, tourism demand even surpassed its pre-pandemic level.</p>
<p>This may be great <a href="https://skift.com/insight/state-of-travel/">news economically</a>, but there’s concern that a return to the status quo is already showing dire environmental and social consequences. </p>
<p>The summer saw record-breaking heatwaves across many parts of the world. People
were forced to flee <a href="https://www.theguardian.com/world/2023/jul/24/greece-wildfires-corfu-evia-rhodes-heatwave-northern-hemisphere-extreme-weather-temperatures-europe">wildfires in Greece</a> and <a href="https://www.independent.co.uk/climate-change/news/hawaii-fires-update-biden-b2393188.html">Hawaii</a>, and extreme <a href="https://www.manchestereveningnews.co.uk/news/world-news/foreign-office-issues-spain-weather-27339111">weather warnings</a> were issued in many popular holiday destinations like Portugal, Spain and Turkey. Experts <a href="https://theconversation.com/european-heatwave-whats-causing-it-and-is-climate-change-to-blame-209653">attributed these extreme conditions</a> to climate change.</p>
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Read more:
<a href="https://theconversation.com/european-heatwave-whats-causing-it-and-is-climate-change-to-blame-209653">European heatwave: what’s causing it and is climate change to blame?</a>
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<p>Tourism is part of the problem. The tourism sector <a href="https://wttc.org/Portals/0/Documents/Reports/2021/WTTC_Net_Zero_Roadmap.pdf">generates around one-tenth</a> of the greenhouse gas emissions that are driving the climate crisis.</p>
<p>The negative impacts of tourism on the environment have become so severe that some are suggesting drastic changes to our travel habits are inevitable. In a <a href="https://www.intrepidtravel.com/sites/intrepid/files/basic_page/files/A%20Sustainable%20Future%20For%20Travel%20From%20Crisis%20To%20Transformation-231016-02.pdf">report</a> from 2023 that analysed the future of sustainable travel, tour operator Intrepid Travel proposed that “carbon passports” will soon become a reality if the tourism industry hopes to survive. </p>
<h2>What is a carbon passport?</h2>
<p>The idea of a carbon passport centres on each traveller being assigned a yearly carbon allowance that they cannot exceed. These allowances can then “ration” travel. </p>
<p>This concept may seem extreme. But the idea of personal carbon allowances is not new. A <a href="https://publications.parliament.uk/pa/cm200708/cmselect/cmenvaud/565/565.pdf">similar concept</a> (called “personal carbon trading”) was discussed in the House of Commons in 2008, before being shut down due to its perceived complexity and the possibility of public resistance. </p>
<p>The <a href="https://www.nature.org/en-us/get-involved/how-to-help/carbon-footprint-calculator/#:%7E:text=A%20carbon%20footprint%20is%20the,is%20closer%20to%204%20tons.">average annual carbon footprint</a> for a person in the US is 16 tonnes – one of the highest rates in the world. In the UK this figure sits at 11.7 tonnes, still more than five times the figure recommended by the <a href="https://www.openaccessgovernment.org/the-average-british-carbon-footprint-is-five-times-over-paris-agreement-recommendations/152669/#:%7E:text=Despite%20rising%20environmental%20awareness%20across,equivalent%20(tCO2e)%20per%20year.">Paris Agreement</a> to keep global temperature rise below 1.5°C. </p>
<p>Globally, the average annual carbon footprint of a person is closer to 4 tonnes. But, to have the best chance of preventing temperature rise from overshooting 2°C, the average global carbon footprint <a href="https://www.nature.org/en-us/get-involved/how-to-help/carbon-footprint-calculator/#:%7E:text=Globally%2C%20the%20average%20carbon%20footprint,tons%20doesn't%20happen%20overnight!">needs to drop</a> to under 2 tonnes by 2050. This figure equates to around <a href="https://www.theguardian.com/environment/ng-interactive/2019/jul/19/carbon-calculator-how-taking-one-flight-emits-as-much-as-many-people-do-in-a-year">two return flights</a> between London and New York. </p>
<p>Intrepid Travel’s report predicts that we will see carbon passports in action by 2040. However, <a href="https://www.politico.eu/article/travel-short-haul-flights-europe-under-fire-climate-change-cop26/">several laws and restrictions</a> have been put in place over the past year that suggest our travel habits may already be on the verge of change.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Boeing 777 with Manhattan in the background lining up on at JFK airport in New York." src="https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=155&fit=crop&dpr=1 600w, https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=155&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=155&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=195&fit=crop&dpr=1 754w, https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=195&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/556889/original/file-20231031-23-kfakh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=195&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Taking a flight from London to New York generates about 986kg of CO₂ per passenger.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/new-york-january-2-boeing-777-93592174">Eliyahu Yosef Parypa/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Targeting air travel</h2>
<p>Between 2013 and 2018, the amount of CO₂ emitted by commercial aircrafts worldwide <a href="https://theicct.org/sites/default/files/publications/ICCT_CO2-commercl-aviation-2018_20190918.pdf">increased by 32%</a>. Improvements in fuel efficiency are slowly reducing per passenger emissions. But <a href="https://www.sciencedirect.com/science/article/pii/S1352231014004889">research</a> from 2014 found that whatever the industry’s efforts to reduce its carbon emissions, they will be outweighed by the growth in air traffic. </p>
<p>For emission reductions to have any meaningful effect, ticket prices would have to rise by 1.4% each year, discouraging some people from flying. However, in reality, <a href="https://www.climatecentral.org/news/increase-in-flights-will-outweigh-carbon-cuts-17875">ticket prices are falling</a>.</p>
<p>Some European countries are beginning to take measures to reduce air travel. As of April 1 2023, passengers on short-haul flights and older aircraft in Belgium have been <a href="https://www.euronews.com/green/2022/12/12/private-jets-and-short-haul-flights-face-pollution-busting-tax-increases-in-belgium">subject to increased taxes</a> to encourage alternative forms of travel.</p>
<p>Less than two months later France banned <a href="https://www.bbc.co.uk/news/world-europe-65687665">short-haul domestic flights</a> where the same trip can be made by train in two-and-a-half hours or less. <a href="https://businesstravelerusa.com/news/spain-to-follow-frances-lead-plans-to-ban-short-haul-domestic-flights/">Spain</a> is expected to follow suit. </p>
<p>A similar scheme could also be on the horizon for Germany. In 2021, a <a href="https://www.cleanenergywire.org/news/seventy-percent-germans-favour-banning-short-haul-flights-survey">YouGov poll</a> found that 70% of Germans would support such measures to fight climate change if alternative transport routes like trains or ships were available. </p>
<h2>Cruises and carbon</h2>
<p>It’s not just air travel that’s being criticised. An <a href="https://www.transportenvironment.org/wp-content/uploads/2023/06/The-return-of-the-cruise-June-2023.pdf">investigation</a> by the European Federation for Transport and Environment in 2023 found that cruise ships pump four times as many sulphuric gases (which are proven to cause acid rain and <a href="https://www.forbes.com/sites/jamesellsmoor/2019/04/26/cruise-ship-pollution-is-causing-serious-health-and-environmental-problems/?sh=468ee2f637db">several respiratory conditions</a>) into the atmosphere than all of Europe’s 291 million cars combined. </p>
<p>Statistics like these have forced European destinations to <a href="https://www.ft.com/content/8727387d-590d-43bd-a305-b5ec208a4dfe">take action</a> against the cruise industry. In July, Amsterdam’s council <a href="https://www.bbc.co.uk/news/world-europe-66264226">banned cruise ships</a> from docking in the city centre in a bid to reduce tourism and pollution – an initiative that has shown success elsewhere.</p>
<p>In 2019 Venice was the most polluted European port, due to large numbers of cruise ship visits. But it dropped to 41st place in 2022 after a ban on large cruise ships entering the city’s waters <a href="https://www.transportenvironment.org/discover/europes-luxury-cruise-ships-emit-as-much-toxic-sulphur-as-1bn-cars-study/">reduced air pollutants from ships</a> in Venice by 80%.</p>
<figure class="align-center ">
<img alt="Gondolas in the foreground of a huge cruise ship in Venice." src="https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/556894/original/file-20231031-23-krj8r8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In 2022, Venice imposed a ban on large cruise ships entering the city’s waters.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/gondolas-on-background-huge-cruise-ship-243221659">Ugis Riba/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Changing destinations</h2>
<p>Intrepid Travel’s report also highlights that not only how we travel, but <a href="https://joint-research-centre.ec.europa.eu/jrc-news-and-updates/global-warming-reshuffle-europes-tourism-demand-particularly-coastal-areas-2023-07-28_en">where we travel</a> will soon be impacted by climate change. Boiling temperatures will probably diminish the allure of traditional beach destinations, prompting European tourists to search for cooler destinations such as Belgium, Slovenia and Poland for their summer holidays. </p>
<p><a href="https://www.travelweekly.com/Travel-News/Tour-Operators/Travelers-seek-cooler-destinations-this-summer">Several travel agencies</a> reported seeing noticeable increases in holiday bookings to cooler European destinations like Scandinavia, Ireland and the UK during 2023’s peak summer travel months.</p>
<p>Whatever the solution may be, changes to our travel habits look inevitable. Destinations across the globe, from <a href="https://www.theneweuropean.co.uk/barcelonas-war-on-tourism-ada-colau/">Barcelona</a> to the <a href="https://www.dw.com/en/italy-tourism-bans-controls-fees-restrictions/a-66453047">Italian riveria</a> and even <a href="https://theconversation.com/death-on-everest-the-boom-in-climbing-tourism-is-dangerous-and-unsustainable-114033">Mount Everest</a> are already calling for limits on tourist numbers as they struggle to cope with crowds and pollution. </p>
<p>Holidaymakers should prepare to change their travel habits now, before this change is forced upon them. </p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p class="fine-print"><em><span>Ross Bennett-Cook does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The clock could be ticking for the travel industry unless action is taken to change our travel habits.Ross Bennett-Cook, Visiting Lecturer, School of Architecture + Cities, University of WestminsterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2107782023-08-09T12:55:43Z2023-08-09T12:55:43ZAir travel is in a rut – is there any hope of recapturing the romance of flying?<figure><img src="https://images.theconversation.com/files/540440/original/file-20230801-15-96mm6.jpg?ixlib=rb-1.1.0&rect=6%2C0%2C4019%2C2685&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The high-risk adventure of air travel has been subdued, yet today's long flights can paradoxically feel torturous.</span> <span class="attribution"><span class="source">Christopher Schaberg</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Amelia Earhart broke a transcontinental speed record 90 years ago, in July 1933, by flying <a href="https://airandspace.si.edu/multimedia-gallery/web11183-2009640jpg">her signature red Lockheed Vega</a> from Los Angeles to New Jersey in just 17 hours, seven and a half minutes. Earlier that year, Earhart had flown as an observer on a Northwest Airways winter flight across the U.S., testing the possibilities of a “Northern Transcontinental” route. </p>
<p>Because those early airplanes couldn’t reach high altitudes, they weaved through dangerous peaks and the erratic weather patterns that mountain ranges helped create. One co-pilot <a href="https://www.deltamuseum.org/about-us/blog/from-the-hangars/2019/07/24/delta-stories-amelia-earhart">remembers the journey</a> as “seat-of-the-pants flying across the Dakota and Montana plains and through, over and around the Western mountain ranges.” </p>
<p>How does air travel today compare? </p>
<p>I’ve studied <a href="https://www.theatlantic.com/technology/archive/2018/02/engine-failure/552959/">airplane technology</a>, <a href="https://www.theatlantic.com/technology/archive/2013/09/a-forgettable-passage-to-flight/279346/">airport design</a> and <a href="https://www.upress.umn.edu/book-division/books/grounded">cultural attitudes</a> toward air travel, and I’ve noticed how aspects of flying seem to have calcified over time. </p>
<p>Long-distance flight <a href="https://theconversation.com/longing-for-the-golden-age-of-air-travel-be-careful-what-you-wish-for-34177">advanced rapidly between the 1930s and the early 1960s</a>, shaving off the number of hours in the sky by half. But over the past 60 years, the duration of such flights has remained roughly the same. Meanwhile, the ecosystem of air travel has grown more elaborate, often leaving passengers squirming in their seats on the tarmac before or after flight. </p>
<p>Coast-to-coast air travel is in a rut – but there are still efforts to improve this mode of transit.</p>
<h2>Just another ordinary miracle</h2>
<p>Transcontinental air journeys are clearly different 90 years after Earhart’s record-breaking exploratory flights: Travelers now take such trips for granted, and often find them to be pure drudgery. </p>
<p>In 2018, <a href="https://thepointsguy.com/reviews/united-757-200-first-class-ewr-sea/">travel blogger Ravi Ghelani reviewed in minute detail</a> a United Airlines flight from Newark, New Jersey, to Seattle – roughly the same northern route that Earhart explored in 1933. </p>
<p>But for Ghelani, seated in first class, it wasn’t the terrain or frigid temperatures that were the most cumbersome part of his adventure. It was a cheap complimentary blanket, which “barely qualified as one – it was very thin, very scratchy.” </p>
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<a href="https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Black and white photo of woman smiling and waving in front of an airplane." src="https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=807&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=807&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=807&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1015&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1015&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541779/original/file-20230808-21-f9i0u2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1015&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Amelia Earhart grins in Newark, N.J., after completing her first nonstop flight across the U.S. in 1932.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/newark-new-jersey-a-wide-grin-covers-the-face-of-amelia-news-photo/104404070?adppopup=true">Keystone-France/Getty Images</a></span>
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<p>The dreaded blanket reappears in Ghelani’s summary of his trip: “My main qualm with this flight was the lack of a decent blanket – the tiny, scratchy blanket that was provided wasn’t cutting it for the six-hour flight.” </p>
<p>I can imagine Earhart rolling in <a href="https://airandspace.si.edu/stories/editorial/legend-amelia-earharts-disappearance">her watery grave</a>: “You zip across the continent in six hours and you complain about a scratchy blanket?”</p>
<p>Yet Ghelani’s account of a mundane cross-country flight reveals a truth: Commercial air travel just isn’t the adventure it was back in Earhart’s time.</p>
<p>As one captain of a major U.S. airline who regularly flies long routes told me, “Today jetliners fly across the country from Los Angeles to New York, or Boston to Seattle, full of passengers oblivious to the commonplace practice it has become.” </p>
<p>This pilot compared coast-to-coast flights to “iPhones, microwaves or automobiles” – just one more ordinary miracle of modern life. </p>
<h2>Little indignities multiply</h2>
<p>The high-risk adventure of air travel has been subdued, yet long flights today can paradoxically feel torturous. </p>
<p>As philosopher Michael Marder puts it in his 2022 book “<a href="https://mitpress.mit.edu/9780262543712/philosophy-for-passengers/">Philosophy for Passengers</a>”: “When crew members wish passengers a ‘pleasant journey,’ I hear a dash of cruel irony in their words. How pleasant can the passenger experience be when you are crammed in your seat, with little fresh air, too hot or miserably cold, and sleep deprived?” </p>
<p>I asked my colleague and <a href="http://airplanereading.org/story/55/frequent-flight">frequent flier</a> Ian Bogost about his experience of coast-to-coast trips, and his reply was illuminating: “The same trip seems to get longer every year, and less comfortable. There are reasons – consolidation, reduced routes, pilot and air-traffic labor shortages, decaying technical infrastructure – but it still feels like moving backwards.” In spite of widespread attempts to update aircraft and modernize terminals, the vast system of air travel can seem cumbersome and outdated. </p>
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<img alt="Glum-looking people in an airport terminal stand in a line that snakes out of the frame." src="https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=404&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=404&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=404&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=507&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=507&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541783/original/file-20230808-19-5kb2r6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=507&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Passengers wait in line amid a series of cancellations at Newark (N.J.) International Airport in June 2023.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/people-queue-for-their-flight-reschedule-inside-of-the-news-photo/1259132586?adppopup=true">Kena Betancur/Getty Images</a></span>
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<p>Recently at The Atlantic, reporter <a href="https://www.theatlantic.com/technology/archive/2023/07/clear-airport-security-lines-tsa-infrastructure/674809/">Amanda Mull wrote about</a> the biometric screening company Clear, describing this firm’s high-tech service to skip the ubiquitous toil of identity checks before flight, at the cost of surrendering some privacy and personal information. Mull concludes the reason more travelers will likely enroll in this service is that “traversing American airport security is simply that grim.” </p>
<p>For Mull, the adventure of contemporary air travel isn’t the destination, or even the journey itself – it’s what you must do to get through the airport. </p>
<p>Still, it’s worth noting that the majority of the human population has never boarded an airplane; flying cross-country remains <a href="https://www.smithsonianmag.com/air-space-magazine/how-much-worlds-population-has-flown-airplane-180957719/">a relatively exclusive experience</a>. For most people, the closest they’ll get to a coast-to-coast flight is seeing a small white scratch across the sky, as another airliner makes its arc at 35,000 feet. </p>
<h2>2 futures of cross-country flight</h2>
<p>Coast-to-coast travel is no longer about breakneck speed or defying elemental odds, and Earhart’s quests to push the limits of aviation couldn’t be further from the bland routines of contemporary air travel. Nor does it involve people dressing to the hilt to step aboard a jetliner for the first time, with passengers stowing their fancy hats in spacious overhead bins. </p>
<p>Where are the new frontiers for transcontinental flight today? </p>
<p>One area of innovation is in a greener form of flight. Solar Impulse, a completely solar-powered plane, took two months to fly coast-to-coast in 2013. It averages a plodding 45 mph at cruising altitude. As <a href="https://apnews.com/ded34ccc19f24aeea67ba3da130a2be0">The Associated Press reported</a>: “Solar Impulse’s creators view themselves as green pioneers – promoting lighter materials, solar-powered batteries, and conservation as sexy and adventurous. Theirs is the high-flying equivalent of the Tesla electric sports car.” Solar Impulse was more recently <a href="https://aviationweek.com/aerospace/aircraft-propulsion/solar-powered-skydweller-completes-first-autonomous-flights?check_logged_in=1">reconfigured as a remotely piloted aircraft</a>, with new experiments in long-distance solar flight underway. </p>
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<img alt="Futuristic looking plane with long wingspan flies over bay and city." src="https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541781/original/file-20230808-16-r1r69n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Solar Impulse 2 flies over the Golden Gate Bridge in San Francisco in 2016.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/solar-impulse-2-a-solar-powered-plane-piloted-by-swiss-news-photo/523604684?adppopup=true">Jean Revillard/Getty Images</a></span>
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<p>The comparison of Solar Impulse to a Tesla is handy because a different extreme can be found in Elon Musk’s company SpaceX. As part of the relentless development of its biggest vehicle, “Starship,” SpaceX has advertised the possibility of “<a href="https://www.spacex.com/human-spaceflight/earth/">point-to-point</a>” travel on Earth: for example, flying on a commercial rocket from Los Angeles to New York in 25 minutes. Never mind the physical tolls of a normal <a href="https://theconversation.com/why-would-anyone-want-to-sit-on-a-plane-for-over-18-hours-an-economist-takes-the-worlds-longest-flight-122433">19-hour flight</a>; it’s hard to imagine what such a brief yet fast trip would feel like, not to mention what sort of class divisions and bleak industrial launch sites such jaunts would rely on.</p>
<p>Get there as fast as possible, using as much fuel as necessary; or glide lazily along, powered by the sun, saving the planet. These are two starkly different visions of coast-to-coast flight, one a dystopian nightmare and the other a utopian dream. </p>
<p>In the middle, there’s what most flying mortals do: wait in lines, board unceremoniously and be relieved if you get to your destination without too much discomfort or delay.</p><img src="https://counter.theconversation.com/content/210778/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Schaberg does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Over the past 60 years, the duration of flights has remained roughly the same, while passengers have been subjected to more indignities, longer waits and more cancellations.Christopher Schaberg, Director of Public Scholarship, Arts & Sciences at Washington University in St. LouisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2075742023-06-14T15:44:53Z2023-06-14T15:44:53ZAviation turbulence soared by up to 55% as the world warmed – new research<figure><img src="https://images.theconversation.com/files/531659/original/file-20230613-27-xtjkgf.jpg?ixlib=rb-1.1.0&rect=1609%2C334%2C1987%2C1917&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Potentially dangerous air turbulence has increased on busy flight routes across the globe.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/cumulonimbus-airplane-landing-storm-clouds-77635738">Jaromir Chalabala/Shutterstock</a></span></figcaption></figure><p>Turbulence on flights isn’t most people’s idea of fun. Drinks start wobbling, hearts start racing and even rational minds start to wonder whether the aircraft can cope. But for the <a href="https://doi.org/10.3389/fpsyg.2016.00754">many people</a> who have a diagnosable fear of flying, turbulence can be terrifying.</p>
<p>That’s why it has given us no great pleasure to have published many studies over the past decade predicting that climate change will worsen turbulence in the future. But these studies have left one gaping question unanswered: given that humans started changing the climate over a century ago, has atmospheric turbulence already started to increase?</p>
<p>According to <a href="https://doi.org/10.1029/2023GL103814">our new study</a>, the answer is a resounding yes. Over the course of the past four decades, severe turbulence has increased on many busy flight routes around the world, including in Europe, the US and the north Atlantic.</p>
<figure class="align-center ">
<img alt="A man sat in front of an airplane window with his head in his hands." src="https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/531664/original/file-20230613-29-5kqhvn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Many people have a diagnosable fear of flying.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/man-sits-front-airplane-window-nervous-2027486114">Marko Aliaksandr/Shutterstock</a></span>
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<h2>The climate–turbulence link</h2>
<p>Clear-air turbulence is an invisible form of rough air that is undetectable by in-flight weather radar and is challenging to forecast. It has nothing to do with clouds and storms, but instead is generated by windshear (wind variations with altitude), which is concentrated largely in the jet streams.</p>
<p>Windshear in the jet streams has <a href="http://dx.doi.org/10.1038/s41586-019-1465-z">increased by 15%</a> at aircraft cruising altitudes since satellites began observing it in 1979. A further increase of <a href="https://doi.org/10.1029/2020EA001556">around 17%–29%</a> is projected by 2100. </p>
<p>These increases are consistent with the expected effects of climate change: <a href="https://feedbackloopsclimate.com/atmosphere">atmospheric feedback loops</a> (where warming generates further warming) are strengthening the temperature differences that generate windshear in the upper atmosphere.</p>
<p>That’s why climate models indicate that clear-air turbulence will <a href="http://dx.doi.org/10.1038/nclimate1866">become much more common in future</a>. Turbulence strong enough to pose an injury risk could <a href="http://dx.doi.org/10.1007/s00376-017-6268-2">double or triple</a> in frequency. </p>
<p>These increases are projected to occur all around the world. Some regions, including North America, the north Atlantic and Europe, are set to experience <a href="http://dx.doi.org/10.1002/2017GL074618">several hundred per cent</a> more turbulence in the coming decades. Every additional 1°C of global warming <a href="https://doi.org/10.1007/s00382-023-06694-x">will increase</a> the amount of turbulence further still.</p>
<p>And for those wondering whether climate models can be trusted with the task of making future turbulence predictions, <a href="http://dx.doi.org/10.1002/qj.4270">the evidence shows that they can</a>. The key factor limiting these predictions is not the performance of the climate models, but our understanding of turbulence itself.</p>
<figure class="align-center ">
<img alt="Weather radar screen inside the cockpit of an aircraft." src="https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=225&fit=crop&dpr=1 600w, https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=225&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=225&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=283&fit=crop&dpr=1 754w, https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=283&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/531933/original/file-20230614-31-aaakle.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=283&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Clear-air turbulence is undetectable by in-flight weather radar.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/cu-on-airplane-weather-radar-screen-2207518471">Supamotionstock.com/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Past turbulence trends</h2>
<p>So have the predicted turbulence increases already begun? A previous analysis of pilot reports of turbulence found <a href="https://doi.org/10.1175/2008JAMC1799.1">evidence of an upward trend</a>. But the short coverage period of 12 years raised questions about whether the increase was genuine or simply a statistical blip. </p>
<p>A longer study analysed 44 years of atmospheric data from 1958 to 2001 and found <a href="https://doi.org/10.1029/2006JD008189">turbulence increases of 40%–90%</a>. But the lack of satellite data for the first half of this period leaves huge observational gaps and raises questions about the reliability of the results.</p>
<p>Our new study analyses turbulence in atmospheric data over the entire meteorological satellite era, from 1979 onwards. Although satellites cannot detect clear-air turbulence, what they can measure is the three-dimensional shape and structure of the jet streams. </p>
<p>From this we can calculate how much clear-air turbulence was being generated by the windshear. Our work has produced the most detailed picture yet of how turbulence has already started to change around the world.</p>
<p>We find that severe clear-air turbulence has increased by 55% over the north Atlantic and 41% over the US since 1979. It does go up and down from one year to the next, but there’s a clear long-term upward trend, consistent with the expected effects of climate change. We find similar increases on other busy flight routes over Europe, the Middle East and the south Atlantic.</p>
<h2>The future of turbulence</h2>
<p>We’ve been warning for the past decade that climate change would increase atmospheric turbulence. And now we see that it is happening. So what can be done to stop the more turbulent atmosphere leading to bumpier flights and more injuries to passengers and crew?</p>
<p>The aviation sector uses <a href="https://www.aviationweather.gov/turbulence/gtg">specialised turbulence forecasts</a> to plot smooth flight routes around turbulent air. These forecasts have improved greatly over the past few decades, but there is still plenty of room for improvement. </p>
<p>Technological advances might one day allow pilots to <a href="http://www.delicat.inoe.ro">remotely sense</a> invisible clear-air turbulence from the cockpit in real time. But high costs mean such technology is not yet viable.</p>
<figure class="align-center ">
<img alt="Fasten Seat belt sign on a plane." src="https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/531936/original/file-20230614-9255-jl252o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The best advice to passengers is to keep your seatbelt fastened.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/security-on-plane-fasten-seat-belt-664653046">marako85/Shutterstock</a></span>
</figcaption>
</figure>
<p>For now, the best advice to passengers is to keep your seatbelt fastened. It’s what you do when driving down the road at 20mph, so it makes sense to do it when hurtling through the sky at 600mph. During a turbulence encounter, remember that turbulence strong enough to cause injuries is relatively rare.</p>
<p>If that thought doesn’t calm you down, we have heard that it helps to order a large drink, place it on the table in front of you and observe how little the liquid surface actually moves. You will see that the turbulent forces are rarely as bad as they feel.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<hr><img src="https://counter.theconversation.com/content/207574/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul D. Williams has received funding from the Royal Society, Natural Environment Research Council, Leverhulme Trust, European Union, and Heathrow Airport.</span></em></p><p class="fine-print"><em><span>Isabel Smith receives funding from NERC</span></em></p><p class="fine-print"><em><span>Mark Prosser receives funding from NERC. </span></em></p>Turbulence strong enough to pose an injury risk could be set to double or triple in frequency in the future.Paul Williams, Professor of Atmospheric Science, University of ReadingIsabel Smith, PhD Candidate, Meteorology, University of ReadingMark Prosser, PhD Student in the Department of Meteorology, University of ReadingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2049962023-05-07T12:38:13Z2023-05-07T12:38:13ZCanadian airlines brace for a summer of change as U.S. airlines consider reforms<figure><img src="https://images.theconversation.com/files/524221/original/file-20230503-19-okemwv.JPG?ixlib=rb-1.1.0&rect=399%2C296%2C2510%2C1836&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An Air Canada jet takes off from Montréal's Pierre Elliott Trudeau International Airport on June 30, 2022.</span> <span class="attribution"><span class="source">THE CANADIAN PRESS/Graham Hughes</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/canadian-airlines-brace-for-a-summer-of-change-as-u-s--airlines-consider-reforms" width="100%" height="400"></iframe>
<p>The United States Government Accountability Office (GAO) recently issued a report <a href="https://www.gao.gov/assets/gao-23-105524-highlights.pdf">on the causes of flight disruptions before and after the pandemic</a>. The report also outlined the challenges airlines faced managing and responding to these flight disruptions.</p>
<p><a href="https://www.gao.gov/assets/gao-23-105524.pdf">The report</a> was the result of requests made by the U.S. Congress to the GAO to examine key changes in the U.S. passenger airline industry resulting from the pandemic.</p>
<p>For those of us who experienced <a href="https://theconversation.com/air-canada-flight-reductions-faqs-about-the-chaos-in-the-airline-industry-185750">the chaotic Canadian aviation environment last summer</a> — especially those that used Toronto’s Pearson Airport and Montréal’s Trudeau Airport — it is difficult to forget the lines of <a href="https://www.cbc.ca/news/canada/toronto/toronto-pearson-airport-delays-1.6481605">passengers waiting in queues for hours</a>, <a href="http://prod-test.thestar.com/news/gta/2022/06/28/you-%20think-you-have-baggage-luggage-is-piling-up-at-pearson-perplexing-travellers.html">mishandled baggage</a> and <a href="https://globalnews.ca/news/8970277/air-canada-pearson-rank-no-1-delays-worldwide-montreal-check-%20in-freezes/">unprecedented flight delays</a>.</p>
<p>For an industry with extensive regulatory oversight provided by the federal government, it has been interesting to examine and contrast the <a href="https://www.ourcommons.ca/DocumentViewer/en/44-1/TRAN/meeting-26/evidence">parliamentary efforts made in Canada to address flight disruptions</a> with similar efforts being made by U.S. Congress.</p>
<h2>Canadian airline reforms</h2>
<p>Canada’s Standing Committee on Transport, Infrastructure and Communities <a href="https://www.ourcommons.ca/DocumentViewer/en/44-1/TRAN/meeting-27/evidence">held a meeting on Aug. 19, 2022 to hear Omar Alghabra</a>, the minister of transport, voice his concerns about flight delays and cancellations. </p>
<p>The meeting focused on the need to better protect air travellers’ rights in the face of such events. </p>
<p>This focus on passenger rights continues to this day. <a href="https://globalnews.ca/news/9646294/air-passenger-rights-changes-compensation-loopholes/">At the end of April, Alghabra announced reforms</a> for the Canadian Transportation Agency’s appeal-handling process and the Canadian Transportation Act. Airlines will be required to handle claims and provide a response to complaints within 30 days.</p>
<figure class="align-center ">
<img alt="A man wearing a suit and glasses speaks from behind a microphone on a desk. A row of Canadian flags stand behind him." src="https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524217/original/file-20230503-17-n9r1yz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Minister of Transport Omar Alghabra speaks at a news conference on proposed changes to air passenger rights, in Ottawa, on April 24, 2023.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Justin Tang</span></span>
</figcaption>
</figure>
<p>The amendments, which are currently tabled in the House of Commons as part of a budget implementation bill, will affect the penalties air carriers face for violating air passenger protection rights. </p>
<p>In particular, the amendments will increase the maximum fine for violations to $250,000 and charge carriers with the regulatory cost of complaints.</p>
<p>The GAO’s analysis and recommendations, by comparison, are much more detailed.</p>
<h2>U.S. airline reforms</h2>
<p>The U.S. Department of Transportation has <a href="https://www.businessinsider.com/flight-delays-would-mean-compensation-for-customers-under-proposed-rule-2022-8">recently initiated passenger protection regulation development</a> similar to the ones Canada has had in place since 2019.</p>
<p>However, the Department of Transportation has yet to address specific compensation levels for passengers that have experienced flight delays — provisions that have already been adopted by Canada and are <a href="https://eur-lex.europa.eu/legal-%20content/EN/TXT/?uri=LEGISSUM%3Al24173">similar to those in effect in the European Union</a>.</p>
<p>An intriguing element of the GAO report is its review of the U.S. Department of Transportation’s awareness of airline scheduling practices and how such practices have impacted flight delays and cancellations.</p>
<p><a href="https://www.gao.gov/assets/820/819136.pdf">In its report, the GAO stated</a> the department of transportation has the authority to “regulate unfair and deceptive practices of airlines, which includes unrealistic scheduling practices.”</p>
<p>The Department of Transportation defines unrealistic scheduling as “the scheduling of flights that airlines cannot generally and reasonably be expected to fulfill.”</p>
<figure class="align-center ">
<img alt="A woman walks in front of a screen displaying flight schedules." src="https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524216/original/file-20230503-24-1sjo91.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cancelled flights are seen in red on the flight schedules at the Southwest terminal at Los Angeles International Airport in December 2022.</span>
<span class="attribution"><span class="source">(AP Photo/Damian Dovarganes)</span></span>
</figcaption>
</figure>
<p>The report concludes that various stakeholders, including several airlines and worker unions, published unrealistic flight schedules, which carriers cannot reasonably be expected to fulfill.</p>
<p>The Department of Transportation indicated it will make an effort next year to build and sustain its oversight and analysis of airline scheduling practices. This will ensure airlines maintain realistic schedules and minimize the impact of flight disruptions on passengers.</p>
<h2>Lessons for Canada</h2>
<p>It is critical that effort be made to provide fair and meaningful compensation in a timely manner to air passengers that have been subjected to airline delays and cancellations. But it is equally — if not more — important to address the underlying causes of such disruptions.</p>
<p>Effective oversight of published airline schedules must be provided. Canadian air travellers should be able to trust an airline’s published schedule — especially as air travellers often purchase tickets long before their flight. </p>
<p>Should Transport Canada step into this oversight role? It might be time to seriously consider establishing a distinct civil aviation authority, separate from Transport Canada.</p>
<p>Canadians’ patience with the actions of various organizations in Canada’s aviation sector has been wearing thin. At the same time, <a href="https://www.commondreams.org/news/united-ceo-airlines-scheduling-flights">rumblings of a return to regulation is starting up</a> in the U.S. airline industry.</p>
<p>Canada’s <a href="https://www.thecanadianencyclopedia.ca/en/article/transportation-regulation">experiment with deregulation occurred close to 40 years ago</a>, but airline scheduling oversight might be one of several areas ripe for similar scheduling reforms in the face of airline disruptions.</p><img src="https://counter.theconversation.com/content/204996/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Gradek does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>While it is critical that air passengers be compensated for airline delays and cancellations, it is equally — if not more — important to address the underlying causes of such disruptions.John Gradek, Faculty Lecturer and Program Co-ordinator, Supply Chain, Logistics and Operations Management, McGill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1988532023-02-07T22:01:18Z2023-02-07T22:01:18ZAfter months of chaos and disruption, has the Canadian commercial aviation industry learned its lesson?<figure><img src="https://images.theconversation.com/files/508494/original/file-20230206-21-w2ddtu.JPG?ixlib=rb-1.1.0&rect=13%2C85%2C2856%2C1796&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The last seven months have seen delays, cancellations, mishandled baggage and miscommunication at Canadian airlines.</span> <span class="attribution"><span class="source">THE CANADIAN PRESS/Graham Hughes</span></span></figcaption></figure><p>Canadian air travellers can finally breathe a sigh of relief. The chaos at airlines and airports appears to finally be over, allowing travellers to once again take to the skies without frustrating delays and cancellations.</p>
<p>But how long will this relief last? Spring Break and the corresponding surge in holiday travel are just around the corner. </p>
<p>Will Canadian commercial aviation prove to have learned its lesson from the last seven months of <a href="https://theconversation.com/air-canada-flight-reductions-faqs-about-the-chaos-in-the-airline-industry-185750">delays, cancellations</a>, <a href="https://www.cbc.ca/news/business/missing-baggage-air-canada-1.6727981">mishandled baggage</a> and <a href="https://theconversation.com/passengers-need-more-than-apologies-from-airlines-after-holiday-chaos-198377">miscommunication</a>? </p>
<p>And if it hasn’t, how can Canadians better prepare themselves for potential disruptions in the future?</p>
<h2>Summer airline chaos</h2>
<p>In early 2022, Canadian air carriers celebrated when <a href="https://www.cbc.ca/news/canada/edmonton/covid-alta-edmonton-kenney-1.6343576">COVID-19 restrictions were lifted</a>. <a href="https://media.aircanada.com/2022-02-22-Air-Canada-Expands-its-Summer-2022-International-Schedule-Relaunching-34-Routes-to-Europe,-Asia,-Africa-and-The-Middle-East">Air Canada</a> and <a href="https://www.westjet.com/en-ca/news/2022/welcome-back-to-the-skies-canada">WestJet</a> announced significant increases in their summer 2022 operations, touting a relaunch of services to regain traffic and revenue lost during 2020 and 2021 from service interruptions.</p>
<p>Canadian air travellers welcomed these services back, anxious to shed the yoke of COVID-19 travel restrictions and return to the wanderlust of seeing the world in person. </p>
<p>As summer 2022 flights filled with travellers, faint alarm bells were heard about <a href="https://www.cbc.ca/news/business/air-canada-flights-july-august-reductions-1.6506451">the aviation infrastructure’s ability to accommodate operations</a> amid the influx. These alarm bells grew louder when passengers were subjected to long wait times, both at departure and arrival. </p>
<p>Flight delays and cancellations quickly became the norm at major Canadian airports. Toronto Pearson International Airport and Montreal-Trudeau International Airport <a href="https://www.cnn.com/travel/article/worst-airports-delays-cancellations-summer-2022/index.html">led the world in flight disruptions</a> during the peak summer months.</p>
<figure class="align-center ">
<img alt="A man in a suit and tie wearing square glasses looks off-camera as he speaks" src="https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508490/original/file-20230206-21-dt35qf.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Federal Transport Minister Omar Alghabra speaks with reporters before appearing as a witness at a House of Commons Standing Committee on Transport, Infrastructure and Communities in Ottawa in January 2023. The committee is looking into the air passenger protection regulations following travel complications over the holiday season.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Spencer Colby</span></span>
</figcaption>
</figure>
<p>There was no shortage of finger-pointing when it came to laying blame for the cause of the summer chaos. <a href="https://www.ourcommons.ca/DocumentViewer/en/44-1/TRAN/meeting-27/evidence">Transport Minister Omar Alghabra stated</a> in August 2022:</p>
<blockquote>
<p>“In May, all agencies, companies and airports had a massive labour shortage compared with the surge in demand that occurred then. We acted quickly. We were preparing for it, but the surge ended up being beyond what was expected.”</p>
</blockquote>
<p>It’s clear the federal government and airlines misjudged the ability of airport infrastructure to handle the sheer volume of air travellers. While the minister may have stated the surge was unexpected, it appears as though <a href="https://www.cnbc.com/2022/07/21/airlines-temper-flying-ambitions-after-chaotic-travel-rebound.html">airlines knew about passenger volumes</a> but <a href="https://www.businessinsider.com/airline-workers-summer-flight-chaos-is-deepening-tension-with-management-2022-8">didn’t listen to workers</a>.</p>
<h2>Holiday airline chaos</h2>
<p>Fast forward to December 2022. While Mother Nature received the lion’s share of blame for disrupting air services during the winter months, it is once again evident that <a href="https://globalnews.ca/news/9362160/edmonton-calgary-vancouver-airport-stranded-passengers-delays-cancelled-flights/">neither airports nor airlines were adequately prepared</a>. </p>
<p>While staffing levels were <a href="https://www.cbc.ca/news/business/air-canada-summer-service-1.6553708">touted to have reached pre-pandemic levels</a>, a lack of winter conditions experience and poor operations planning appear to be major contributing factors to the chaos.</p>
<figure class="align-center ">
<img alt="People sit on the floor and on benches in an airport" src="https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508493/original/file-20230206-13-wepocu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">People sit on the floor at Vancouver International Airport after a snowstorm disrupted operations leading to cancellations and major delays, in Richmond, B.C., in December 2022.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Darryl Dyck</span></span>
</figcaption>
</figure>
<p>Disruption has also been the hallmark of the United States’ last six months, from summer delays to the <a href="https://www.usatoday.com/story/travel/airline-news/2023/01/11/faa-computer-outage-delays-flights/11030719002/">Federal Aviation Administration’s system failure</a> to <a href="https://www.cnn.com/2022/12/27/business/southwest-airlines-service-meltdown/index.html">Southwest Airlines’ computer system meltdown</a>. </p>
<p>Perhaps the current state of commercial aviation can <a href="https://www.nbcnews.com/business/consumer/whats-going-on-with-air-travel-today-how-to-fix-it-rcna66501">best be summarized by Scott Kirby, CEO of United Airlines</a>. When asked about his views of the airline industry in 2023, he said:</p>
<blockquote>
<p>“The system simply can’t handle the volume today, much less the anticipated growth. There are a number of airlines who cannot fly their schedules. The customers are paying the price.”</p>
</blockquote>
<p>The U.S. Secretary of Transportation has been the focus of media attention for <a href="https://www.nytimes.com/2023/01/20/us/politics/pete-buttigieg-southwest-faa.html">his pronouncements on the need for airlines and airports</a> to increase their customer service levels and ensure flight schedules are realistic and operable.</p>
<h2>What to expect in the future</h2>
<p>What might Canadian air travellers expect over the next few months? Some airlines, like <a href="https://www.cbc.ca/news/canada/saskatchewan/sunwing-cancels-regina-service-1.6716836">Sunwing</a>, have reduced services to operate a schedule that is more likely to meet customer expectations.</p>
<p>Other carriers remain operating at an aggressive level, looking to maximize their revenue, profit and targets. While the <a href="https://www.ctvnews.ca/politics/airport-delays-transport-minister-says-feds-not-asking-airlines-to-cut-back-flights-1.5907284">minister of transport has stated</a> he won’t ask airlines to cut back their schedules, air services need to ensure infrastructure and staffing levels are adequate enough to prevent further disruptions.</p>
<p>In contrast to Canada, the U.S. Transportation Department recognizes its role in reviewing unrealistic airline scheduling and <a href="https://thehill.com/policy/transportation/3831396-transportation-department-looking-into-whether-unrealistic-scheduling-played-role-in-southwest-holiday-meltdown/">is actively investigating such practices</a>.</p>
<figure class="align-center ">
<img alt="The silhouette of a man walks in front of a massive window overlooking an airport tarmac with a WestJet plane sitting on it" src="https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/508492/original/file-20230206-23-prvko2.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">WestJet is one of the airlines that has announced reductions in services to better meet customer expectations for air travel services.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Jeff McIntosh</span></span>
</figcaption>
</figure>
<h2>Dealing with disruptions</h2>
<p>Short of increased airline regulation in Canada, how can air travellers deal with the potential for continued disruption? </p>
<p>The Air Passenger Protection Regulations of 2019, <a href="https://otc-cta.gc.ca/eng/air-passenger-protection-regulations">which were amended in 2022</a>, offer passengers a way to receive compensation for delays, cancellations and other mishandling. However, the realities of processing a claim through the Canadian Transportation Agency are daunting, to say the least.</p>
<p>The Canadian Transportation Agency <a href="https://www.ctvnews.ca/canada/backlog-of-airline-complaints-balloons-by-6-395-since-december-travel-chaos-canadian-transportation-agency-1.6254745">currently has a backlog of over 36,000 appeals</a> requiring investigation and resolution, meaning complainants are facing wait times of up to 18 months for their appeal to be addressed. </p>
<p>The minister of transport has <a href="https://www.travelweek.ca/news/more-changes-for-air-passenger-protection-regulations-on-the-way-alghabra/">promised a review of the air passenger protection regulations</a> to address enforcement and efficiency. Canada should take inspiration from <a href="https://www.europarl.europa.eu/cmsdata/226409/Case_analysis_on_the_transposition_and_implementation_of_the_Regulation_on_air_passenger_rights_.pdf">the European Union’s approach to mishandling compensation</a>, where the onus is on air carriers to defend their rationale for not paying compensation.</p>
<p>Canadians have great expectations for the actions about to be taken by the minister of transport and the Canadian government. Patience with the air travel system has worn thin and changes are most definitely needed. I, for one, am looking forward to a solution that quells Canadians’ anxiety on air travel.</p><img src="https://counter.theconversation.com/content/198853/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Gradek does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The chaos at airlines and airports appears to finally be over, but will the relief last? Or will Canadians have to brace themselves for more delays, cancellations and miscommunications?John Gradek, Faculty Lecturer and Program Co-ordinator, Supply Chain, Logistics and Operations Management, McGill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1977542023-01-12T21:13:47Z2023-01-12T21:13:47ZWhat is the FAA’s NOTAM? An aviation expert explains how the critical safety system works<p><em>Late in the evening of Jan. 10, 2023, an important digital system known as NOTAM run by the Federal Aviation Administration <a href="https://www.npr.org/2023/01/11/1148340708/faa-notam-ground-stop-flight-delay">went offline</a>. The FAA was able to continue getting necessary information to pilots overnight using a phone-based backup, but the stopgap couldn’t keep up with the morning rush of flights, and on Jan. 11, 2022, the FAA grounded all commercial flights in the U.S. In total, <a href="https://www.npr.org/2023/01/11/1148340708/faa-notam-ground-stop-flight-delay">nearly 7,000 flights</a> were canceled. <a href="https://aviation.osu.edu/people/strzempkowski.1">Brian Strzempkowksi</a> is the interim director of the Center for Aviation Studies at The Ohio State University and a commercial pilot, flight instructor and dispatcher. He explains what the NOTAM system is and why planes can’t fly if the system goes down.</em></p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A number of planes line up for takeoff on a runway." src="https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=200&fit=crop&dpr=1 600w, https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=200&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=200&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=251&fit=crop&dpr=1 754w, https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=251&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/504319/original/file-20230112-60827-1gx11f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=251&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Pilots must check the NOTAM system before takeoff so that they know about any situations that may affect safety.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:6_planes_in_one_photo!_United_Airlines_Boeing_787,_747,_777,_WOW_Airbus_A330_takeoff,_SWA_737,_United_CRJ_landing_SFO_runway_28_L_and_R_(30480576501).jpg#/media/File:6_planes_in_one_photo!_United_Airlines_Boeing_787,_747,_777,_WOW_Airbus_A330_takeoff,_SWA_737,_United_CRJ_landing_SFO_runway_28_L_and_R_(30480576501).jpg">Bill Abbott/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>What is NOTAM?</h2>
<p>Aviation is full of acronyms, and Notice to Air Missions, or NOTAM, is one acronym that pilots learn early on in their training. A NOTAM is quite simply a message that is disseminated to flight crews of every aircraft in the U.S.</p>
<p>The NOTAM system is a computer network run by the Federal Aviation Administration that provides real-time updates to crews about situations relating to weather, infrastructure, ground conditions or anything else that may <a href="https://www.faa.gov/sites/faa.gov/files/regulations_policies/handbooks_manuals/aviation/phak/03_phak_ch1.pdf">affect the safety of flight</a>. Trained professionals – like air traffic controllers, airport managers, airport operations personnel and FAA personnel in charge of national airspace infrastructure – can access the system and enter any information they need to share broadly.</p>
<p>Pilots, air traffic controllers and anyone else who needs to know about flying conditions can access the NOTAM system and make appropriate changes to planned flights. It’s similar to checking the traffic on your phone or on the local news before you head to work in the morning. A traffic report will inform you of potential hazards or backups on the roadways that may lead you take a different route to work.</p>
<h2>What’s in the NOTAM system and how is it used?</h2>
<p>NOTAMs are issued for a wide range of reasons. Some of the notices are good to know but don’t affect a flight – such as personnel mowing grass alongside a runway or a crane working on a building next to the airport. Others are more critical, such as a runway being closed because of snow, ice or damage, forcing a plane to take off or land on a different runway. Changes in access to airspace are also logged with a NOTAM. For example, airspace is always closed above the president and when he or she travels; a NOTAM will alert pilots to changes in airspace closures.</p>
<p>Pilots <a href="https://pilotweb.nas.faa.gov/PilotWeb/">review these NOTAMs</a> during their preflight briefings. Generally this is done digitally using a computer, but pilots and air traffic controllers can also access the system by calling flight service briefers, who can share <a href="https://www.1800wxbrief.com/Website/home;jsessionid=624B2EEA87E48B2E1DF67CB0B791E054?desktop=true#!/phone-numbers-quick-steps">live weather and NOTAM information</a>. Airline pilots also rely on their dispatchers to relay any relevant NOTAMs not only before but also during the flight. </p>
<p>The NOTAMs themselves use a lot of abbreviations and are often cryptic to nonaviation folks, but a small amount of text <a href="https://www.notams.faa.gov/downloads/contractions.pdf">can carry a lot of information</a>. Hundreds of different acronyms can convey a range of information, from taxiway closures to certain types of airport lighting being out of service to a notice that some pavement markings may be obscured.</p>
<p>But not all NOTAMs are straightforward. I remember once seeing a notice from an airport alerting pilots that a fire department was conducting a controlled burn of a house nearby.</p>
<h2>Why can’t you fly if the NOTAM system is down?</h2>
<p>The Federal Aviation Authority requires flight crews to <a href="https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F/part-91/subpart-B/subject-group-ECFRe4c59b5f5506932/section-91.103">review NOTAMs before every flight</a> for safety reasons. Without access to this information, a plane cannot legally depart, because there may be an unknown hazard ahead. </p>
<p>As an example, a pilot departing Seattle to fly to Miami would need to know that the Miami airport is open, that the runways are clear and that all the navigational sources – like GPS signals and ground-based navigation antennas – that a pilot may use while in the air are working. Theoretically, they could call the Miami airport and ask, and then call the person who oversees every navigational aid on their route, but that would take a lot of time. A much more efficient way to gather this information before and during a flight is to use the NOTAM system. </p>
<p>At the end of the day, the NOTAM system is about safety. When the system is down, pilots can’t fly as safely. It is for good reason that planes don’t go anywhere unless the NOTAM system is up and running.</p><img src="https://counter.theconversation.com/content/197754/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brian Strzempkowski does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The Notices to Air Mission system failed on Jan. 10, 2023, leading to thousands of canceled flights. The system is where all important safety information for pilots and dispatchers gets posted.Brian Strzempkowski, Interim Director, Center for Aviation Studies, The Ohio State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1948932022-11-21T13:16:29Z2022-11-21T13:16:29ZWhen’s the best time to use frequent flyer miles to book flights? Two economists crunched the numbers on maximizing their dollar value<figure><img src="https://images.theconversation.com/files/496314/original/file-20221120-12-5vwh0m.jpeg?ixlib=rb-1.1.0&rect=54%2C155%2C5020%2C3300&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The value of frequent flyer miles can change significantly in the weeks and months ahead of a given travel date.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/landing-airplane-royalty-free-image/539327295?phrase=airplane%20landing&adppopup=true">Jetlinerimages/E+</a></span></figcaption></figure><p>Traveling during major holidays like Thanksgiving can be expensive, since so many people want to see their friends and families, wherever they might be. </p>
<p>It’s especially hard this year with <a href="https://fred.stlouisfed.org/series/CPIAUCSL">inflation soaring</a> at the fastest pace since the early 1980s. Airline fares <a href="https://fred.stlouisfed.org/series/CUSR0000SETG01#0">were up 43% in October</a> from a year earlier – only a <a href="https://www.bls.gov/news.release/cpi.t02.htm">handful of categories increased by more</a>. </p>
<p>One way to ease the blow to your wallet or purse is by using frequent flyer miles. While there’s <a href="https://doi.org/10.1145/2733384">quite a bit</a> of research on when is the <a href="https://conservancy.umn.edu/handle/11299/215872">best time to use cash</a> to buy flights, <a href="https://www.bu.edu/questrom/profile/huseyin-karaca/">we wondered</a> – as travel lovers – if there’s an optimal time to use miles. So with the help of <a href="https://drive.google.com/file/d/1HikpvLqt_M8OfXrCXta4rm76Z_JreLJt/view">our research assistant</a>, we investigated this question, with a focus on flights over the Thanksgiving holiday. </p>
<h2>Americans return to the skies</h2>
<p>The day before Thanksgiving is one of the busiest days to travel in the U.S. </p>
<p>Before the COVID-19 pandemic upended travel, the Transportation Security Administration <a href="https://www.tsa.gov/coronavirus/passenger-throughput">screened 2.6 million people</a> on Thanksgiving eve of 2019, just shy of the 2.9 million record. While the number plunged in 2020 as demand dropped, it picked up to 2.3 million last year and <a href="https://www.wsj.com/articles/this-thanksgiving-is-expected-to-be-one-of-the-busiest-for-travel-in-decades-11668532148">is expected to return</a> to pre-COVID-19 levels this year. </p>
<p>The surge in demand, along with significantly higher jet fuel costs, are key factors in leading to more expensive air fares. </p>
<p>To offset these higher costs, <a href="https://newsroom.wf.com/English/news-releases/news-release-details/2022/New-Study-Americans-Lean-Into-Credit-Card-Rewards-to-Offset-Rising-Costs--Including-Travel/default.aspx">many consumers</a> may turn to frequent flyer miles – whether accumulated from other travel or from credit cards – to avoid forking over so much cash. </p>
<figure class="align-center ">
<img alt="many people wait in lines at a security checkpoint at an airport" src="https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496244/original/file-20221119-9492-w10x35.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Thanksgiving holiday is one of the busiest travel times of the year.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/OffTheChartsAirlinesHolidayTest/2a0103aedfa842ab93a0f6d0d89d400f/photo?Query=thanksgiving%20air%20travel&mediaType=photo&sortBy=arrivaldatetime:desc&dateRange=Anytime&totalCount=56&currentItemNo=0">AP Photo/Steven Senne</a></span>
</figcaption>
</figure>
<h2>Frequent flying 101</h2>
<p><a href="https://doi.org/10.1080/10253866.2015.1096095">Frequent flyer mile programs started</a> in the late 1970s after the <a href="https://www.faa.gov/about/history/brief_history">federal government stopped regulating</a> airfares. Before the change, fares, routes and schedules for all domestic flights were set by the federal Civil Aeronautics Board. </p>
<p>Besides slashing fares, <a href="https://abcnews.go.com/Travel/airline-frequent-flyer-miles-30-years/story?id=13616082">airlines reacted by creating frequent flyer programs</a>. Texas International Airlines, which ultimately merged with United, and Western Airlines, which later joined Delta, were among the first to institute frequent flyer programs.</p>
<p>In a particular airline’s frequent flyer program, you earn miles when you fly with that airline. Many people get miles by using their credit cards as well. These accumulated miles can then be redeemed for free air travel.</p>
<p>Frequent flyer programs were designed to <a href="https://doi.org/10.1108/02634509810199535">build customer loyalty</a>, as they provide a rebate to regular passengers. They are also <a href="https://hbr.org/1995/05/do-rewards-really-create-loyalty">meant to lock travelers</a> into a particular airline – since they have a strong incentive to only fly with that carrier.</p>
<p>One downside is that many business flyers go out of their way to use their preferred airline, <a href="https://www.informs.org/About-INFORMS/News-Room/Press-Releases/Study-Finds-that-Frequent-Flyer-Programs-Increase-Cost-of-Business-Travel">which boosts their company’s travel costs</a>.</p>
<p>And although airlines use frequent flyer programs to increase customer goodwill, they frequently <a href="https://www.thrillist.com/news/nation/united-airlines-loyalty-program-status-update">change the rules and rewards</a>, which often <a href="https://www.inc.com/jason-aten/delta-just-announced-a-change-that-will-make-people-very-mad-its-actually-a-brilliant-move.html">frustrates customers</a>.</p>
<p><a href="https://doi.org/10.1145/2733384">Researchers have looked</a> at the <a href="https://conservancy.umn.edu/handle/11299/215872">optimal time to buy</a> airplane <a href="https://doi.org/10.1057/s41272-019-00193-7">tickets</a> with cash. In general, <a href="https://www.forbes.com/sites/suzannerowankelleher/2022/08/31/best-time-to-book-a-cheap-flight/?sh=23fdd1e72ebc">they have found prices</a> tend to dip anywhere from two months to three weeks before the travel dates. Prices are highest for those who want to book their flights very early, to lock it in, and last-minute travelers booking just before their departure dates. </p>
<h2>How frequent flyer miles compare</h2>
<p>To see when’s the best time to book with miles, we looked at <a href="https://www.oag.com/busiest-routes-right-now">one of the busiest routes in the U.S.</a> – New York (JFK) to Los Angeles (LAX). Each month, airlines have over a quarter of a million seats flying direct on that route. There are about 30 nonstop flights a day, run by <a href="https://www.aa.com/en-us/flights-from-new-york-to-los-angeles">three</a> <a href="https://www.delta.com/us/en/flight-deals/united-states-flights/flights-to-los-angeles">different</a> <a href="https://www.jetblue.com/destinations/los-angeles-california-flights">airlines</a>.</p>
<p>Starting about three months before Thanksgiving, we collected weekly data from the online booking sites of these three airlines. We tracked the frequent flyer miles needed as well as the price for every coach flight scheduled to take place within one week of Thanksgiving.</p>
<p>As miles are not interchangeable between airlines in general, we needed an alternative measure for more direct comparison between different airlines. So we calculated how much a frequent flyer mile is worth by dividing the number of frequent flyer miles needed by the ticket price. We then compared the dollar worth of 1,000 miles, depending on the airline, when the booking was made and the flight date.</p>
<p><a href="http://businessmacroeconomics.com/">Economic theory</a> tells us that when there is lots of competition and the product is almost identical, competition should result in all businesses charging roughly the same price.</p>
<p>That wasn’t what we found.</p>
<p>In mid-October, Delta was asking 69,000 miles to fly the Tuesday before Thanksgiving. American Airlines was only asking 33,000 miles for roughly the same flight. This means if you have a <a href="https://www.cnbc.com/select/best-travel-credit-cards/">general travel rewards credit card</a> that lets you use miles on different airlines, it pays to shop around.</p>
<p>Just because an airline has a high price in miles doesn’t mean the price will not come down. At the start of November, Delta wanted 69,000 miles to fly at dinnertime on the Tuesday before Thanksgiving. A week later the airline cut the price to 53,000 miles. A week after that, it was down to 36,500 miles, a price drop of almost 50% in two weeks.</p>
<p><iframe id="bakbg" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/bakbg/2/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>While in general the earlier you book, the better, booking too early can cost you. We found the best time to spend your frequent flyer miles for Thanksgiving travel was to book during the first week of October, which was about eight weeks out. In early October, 1,000 frequent flyer miles were worth over $14 in airfare. The last week of October, about four weeks before Thanksgiving, those same miles were only worth shy of $12. </p>
<h2>The best day to fly</h2>
<p>As for what is the best day on which to travel to get the most from your miles, there are two answers. On the Monday before Thanksgiving, your miles are typically worth the most, on average $15 per 1,000 miles. This is in sharp contrast to $11 for the day before Thanksgiving. However, flying Thanksgiving Day itself had required the lowest average number of miles, about 27,000 miles.</p>
<p>If you haven’t booked flights yet, you may be too late to find the best value in frequent flyer miles. However, while we are still gathering and analyzing data, these tips look like they will hold up for future holidays.</p><img src="https://counter.theconversation.com/content/194893/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The value of frequent flyer miles sometimes seems to defy the laws of economics.H. Sami Karaca, Professor of Business Analytics, Boston UniversityJay L. Zagorsky, Clinical associate professor, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1924632022-10-19T15:16:56Z2022-10-19T15:16:56Z3-D techniques shed light on what makes a bird’s lungs so efficient<figure><img src="https://images.theconversation.com/files/490042/original/file-20221017-25-7od4j8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Cinnamon-Chested Bee-Eater is released after being ringed at the National Museum of Kenya.</span> <span class="attribution"><span class="source">Luke Dray/Getty Images</span></span></figcaption></figure><p>Birds are profoundly important animals. As predators, <a href="https://theconversation.com/biodiversity-depends-on-pollinators-a-first-estimate-of-how-many-plants-rely-on-animals-166908">pollinators</a>, seed dispersers, scavengers and <a href="https://theconversation.com/mistletoes-locust-bean-trees-and-birds-work-together-in-nigerias-forest-ecology-177264">ecosystem bioengineers</a>, the world’s 11,000 species of birds play critical roles in the food chain and therefore the existence of animal life. </p>
<p>They have also shaped the advancement of human societies <a href="https://theconversation.com/how-birds-are-used-to-reveal-the-future-130844">culturally</a>, philosophically, artistically, economically and scientifically. Birds feature prominently in the history of painting, poetry, commerce and <a href="https://theconversation.com/birdsong-has-inspired-humans-for-centuries-is-it-music-79000">music</a>. </p>
<p>Since they can easily escape from unsuitable habitats, birds are important “sentinel” animals: the number and diversity of species indicates environmental health. BirdLife International’s <a href="https://www.birdlife.org/state-of-the-worlds-birds/">State of the World’s Birds Report for 2022</a> says that about half of all bird species are decreasing and more than one in eight of them are at risk of extinction.</p>
<p>Knowledge of bird biology and their place in ecosystems contributes to devising conservation efforts. Biology explains why animals behave the way they do and what threatens their survival.</p>
<p>One of the aspects of bird biology that has long interested scientists is their lungs. They are structurally very complex and functionally efficient. Their lungs are what allows birds to fly. Flying uses a huge amount of energy and some birds fly nonstop over <a href="https://theconversation.com/as-far-as-the-moon-and-back-twice-heres-a-look-at-the-most-extraordinary-journeys-migrating-birds-make-168904">very long distances</a> or at very <a href="https://theconversation.com/migratory-birds-found-to-be-flying-much-higher-than-expected-new-research-167582">high altitudes</a> where there is little oxygen.</p>
<p>Even after extensive study, questions about the bioengineering of the avian respiratory system have persisted. They relate to how the airways and blood vessels are shaped, arranged and connected, and how air flows around the lung. </p>
<p>To explore these aspects of the avian lung, my colleagues and I have used a variety of techniques. Three-dimensional (3-D) serial section computer reconstruction is one of them. </p>
<p>Using this technique <a href="https://wap.hillpublisher.com/UpFile/202105/20210518180525.pdf">showed us</a> that the tiny structures (air- and blood capillaries) between which oxygen is exchanged are not the shape they were long thought to be. Because they are so small and so tightly entangled with each other, it wasn’t possible to see their shapes and connections clearly until we used 3-D reconstruction. We were then able to see what makes the bird lung so efficient at taking up the oxygen needed to release energy – key to survival.</p>
<h2>The approach</h2>
<p>For hundreds of years, scientists could only study biological structures in two dimensions – sections of tissue were placed under a transmission microscope. In the late 1970s, the South African-born Nobel prize winner <a href="https://www.nobelprize.org/prizes/medicine/2002/brenner/facts/">Sydney Brenner</a> was the first to apply computing to reconstruct series of sections. More recently, 3-D reconstruction methodologies have revolutionised various fields of biology.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=527&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=527&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490026/original/file-20221017-12-g3xky2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=527&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plate 1: airways, arteries and veins of the fowl lung.</span>
<span class="attribution"><span class="source">John Ndegwa Maina</span></span>
</figcaption>
</figure>
<p>3-D reconstruction <a href="https://wap.hillpublisher.com/UpFile/202105/20210518180525.pdf">showed us</a> that the airways and blood vessels track each other and supply specific parts of the bird’s lung. The various branches of the airway system do not interconnect and neither do the branches of the blood system. We were able to get a much clearer view of the shapes and connections of the air capillaries and blood capillaries in the lung. The compact entwining of the capillaries increases respiratory surface area while minimising the thickness of the blood-gas barrier. </p>
<p>The design of the bird’s lungs forms a highly efficient gas exchange system with large functional reserve. The lungs are ventilated continuously and in one direction (from back to front) with “fresh” air by coordinated actions of the very large air sacs. During every respiratory cycle, the air in the lung is replaced with “clean” air. This maintains a high pressure that drives oxygen into the blood circulating across the lung. It gives birds their flying power. </p>
<p>Our 3-D serial section reconstruction supplied new details and underscored the value of the technique for investigating complex biological structures.</p>
<h2>3-D reconstruction</h2>
<p>3-D reconstruction entails preparing a spatial model of a structure from 2-D images. Because it takes time, a lot of materials and specialised skills, it’s not often used in biological studies. </p>
<p>We used the method on a chicken lung because this is the model animal for study of the biology of birds. </p>
<p>We cut 2,689 serial sections of a chicken lung at a thickness of 8 micrometres (each micrometre is one millionth of a metre). We stained and mounted them onto glass slides, photographed sections and aligned the images for reconstruction using open-source software. </p>
<p>There are other modern 3-D reconstruction methods that are faster, cheaper and easier to use. But 3-D histological serial section reconstruction (building up a picture from thin slices of tissue) remains a very important technique. The reconstructions have better contrast and signal-to-noise ratio (there’s less unwanted information). Also, dyes and markers can be used to enhance identification of structures. </p>
<h2>Bird lung capillaries</h2>
<p>The process showed us that the extremely small terminal respiratory units of the bird lung – long called “air capillaries” – are not so: they are rather rotund structures, interconnected by very narrow passages.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490032/original/file-20221017-21-zpl43s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plate II. Air capillaries (top) and blood capillaries (bottom)</span>
<span class="attribution"><span class="source">John N Maina</span></span>
</figcaption>
</figure>
<p>Moreover, the “blood capillaries” are not “true” capillaries like those found in most other tissues and organs that are much longer than they are wide. They comprise clearly separate parts that are about as long as they are wide and interconnect in 3-D. The air- and the blood capillaries of the bird lung intertwine very tightly in a “honeycomb” arrangement. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=358&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=358&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=358&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=449&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=449&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490037/original/file-20221017-2267-67rk2p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=449&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plate IV. Comparing images.</span>
<span class="attribution"><span class="source">John N Maina</span></span>
</figcaption>
</figure>
<p>Knowing the shape and size of these units provides information about the gas exchange efficiency of the bird’s lung, which is a flow-through system. </p>
<h2>More to come</h2>
<p>As more efficient ways of applying 3-D reconstruction technology are developed, 3-D imaging and animation will become a vital means of research in a biologist’s toolbox. It will be possible to fully conceptualise the forms of structural components and hence allow better understanding of how they work.</p>
<p>Vital insights into the biology of animals, including birds, will allow us to formulate more effective measures that will ensure their conservation in the face of challenges from global warming and environmental pollution.</p><img src="https://counter.theconversation.com/content/192463/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Maina receives funding from the National Research Foundation of South Africa </span></em></p>An understanding of bird biology is the starting point for conservation efforts. 3-D reconstructions of biological structures greatly add to this understanding.John Maina, Professor of Comparative Respiratory Morphology, University of JohannesburgLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1855622022-07-11T12:30:45Z2022-07-11T12:30:45ZD.B. Cooper, the changing nature of hijackings and the foundation for today’s airport security<figure><img src="https://images.theconversation.com/files/473071/original/file-20220707-16-frr26z.jpg?ixlib=rb-1.1.0&rect=180%2C212%2C3291%2C2024&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The hijacking of U.S. aircraft – like the three hijacked in 1970 by the Popular Front for the Liberation of Palestine – made it impossible for American policymakers to ignore the threat.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/terrorists-blow-up-one-of-three-hijacked-airplanes-after-news-photo/514880334?adppopup=true">Bettmann/Getty Images</a></span></figcaption></figure><p>Though many Americans may associate airport security with 9/11, it was a wave of hijackings in the late 1960s and early 1970s that laid the foundation <a href="https://theconversation.com/an-entire-generation-of-americans-has-no-idea-how-easy-air-travel-used-to-be-166082">for today’s airport security protocols</a>.</p>
<p>During that period, a hijacking occurred, on average, <a href="https://today.ku.edu/2019/06/10/first-soviet-hijacking-triggers-insights-cold-war-boundaries">once every five days globally</a>. The U.S. dealt with its own spate of mile-high crimes, convincing reluctant government officials and airport executives to adopt the first important airport security protocols. </p>
<p>The subject of <a href="https://www.imdb.com/title/tt21063148/?ref_=nv_sr_srsg_0">a new Netflix docuseries</a>, hijacker D.B. Cooper emerged as something of a folk hero during this era. While other more violent hijackings might have played a bigger role in prompting early airport security measures, it was the saga of Cooper that captured the imagination of the American public – and helped transform the perception of the overall threat hijackings posed to U.S. air travel and national security. </p>
<h2>Incidents become impossible to ignore</h2>
<p>The first airplane hijacking happened in <a href="https://www.britannica.com/topic/hijacking">1931 in Peru</a>. Armed revolutionaries approached the grounded plane of pilot Byron Richards and demanded that he fly them over Lima so they could drop propaganda leaflets. Richards refused, and a 10-day standoff ensued before he was eventually released.</p>
<p>That remained a somewhat isolated incident until the <a href="https://en.wikipedia.org/wiki/List_of_aircraft_hijackings">late 1940s and 1950s</a>, when several people hijacked airplanes to escape from Eastern Europe to the West. In the context of the Cold War, Western governments granted these hijackers <a href="https://www.ojp.gov/ncjrs/virtual-library/abstracts/hijacking-and-right-asylum-aerial-piracy-and-international-law-p">political asylum</a>. Importantly, none of the airplanes hijacked were flown by U.S. carriers.</p>
<p>Beginning in the early 1960s, however, hijackers began targeting U.S. airlines. Most of these individuals were <a href="https://www.tsi-mag.com/the-cuban-hijackings-their-significance-and-impact-sixty-years-on/">Cubans</a> living in the U.S. who, for one reason or another, wished to return to their native land and were otherwise blocked due to <a href="https://www.thecubareader.com/blog/the-strange-story-of-the-us-cuba-hijacking-accord">the U.S. embargo</a> against Cuba.</p>
<p>U.S. officials responded by <a href="https://www.law.cornell.edu/uscode/text/49/46502">officially and specifically making hijacking a federal crime</a>. Though the new law didn’t stop hijackings altogether, the crime remained relatively rare. When they did occur, they usually didn’t involve much violence.</p>
<p><a href="https://www.aerotime.aero/articles/15042-take-me-to-cuba-the-skyjacking-craze-of-the-1960s">Officials wanted to downplay hijackings as much as possible</a>, and the best way to do this was to simply give the hijacker what they wanted to avert the loss of life. Above all, airline executives wanted to avoid deterring people from flying, so they resisted the implementation of anxiety-inducing security protocols.</p>
<p>That changed in 1968. On July 23 of that year, members of the Popular Front for the Liberation of Palestine <a href="https://www.jpost.com/israel-news/on-this-day-el-al-flight-426-hijacked-by-pflp-674735">hijacked an El Al flight</a> from Rome to Tel Aviv. Though that 39-day ordeal ended without any loss of life, it ushered in a new era of more violent – often politically motivated – hijackings of international airlines. </p>
<p>From 1968 to 1974, U.S. airlines experienced <a href="https://www.vox.com/2016/3/29/11326472/hijacking-airplanes-egyptair">130 hijackings</a>. Many fell into this new category of politically motivated hijackings, including what has become known as the <a href="https://www.hsdl.org/c/tl/dawsons-field-hijackings/">Dawson’s Field hijackings</a>. In September 1970, the Popular Front for the Liberation of Palestine hijacked four aircraft, including three belonging to U.S. carriers, and forced them to land at Dawson’s Field in Libya. No hostage lives were lost, but the hijackers used explosives to destroy all four aircraft.</p>
<figure class="align-center ">
<img alt="Charred tail fin of destroyed plane." src="https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=524&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=524&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473061/original/file-20220707-10739-9fzsly.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=524&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Remains of a Pan Am plane that Palestinian hijackers blew up at Dawson’s Field in Libya in 1970.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/photo-dated-07-september-1970-of-the-debris-left-over-from-news-photo/97635079?adppopup=true">AFP/Getty Images</a></span>
</figcaption>
</figure>
<p>Additionally, and more worrying to U.S. officials, two different groups of hijackers, <a href="https://www.latimes.com/archives/la-xpm-2001-sep-23-mn-48746-story.html">one in 1971</a> and <a href="https://www.freep.com/story/news/local/michigan/detroit/2016/06/06/detroit-skyjacker-airplane-explanation/85314438/">another in 1972</a>, threatened to crash planes into nuclear power plants. </p>
<h2>Cooper inspires copycats</h2>
<p>Amid this dramatic rise in the number of hijackings, on Nov. 24, 1971, a man known to the American public as <a href="https://www.fbi.gov/history/famous-cases/db-cooper-hijacking">D.B. Cooper</a> boarded a Northwest Orient 727 flight from Portland, Oregon, to Seattle. Shortly after takeoff, he showed a stewardess the contents of his briefcase, which he said was a bomb. He then instructed the stewardess to take a note to the cockpit. In it, he demanded US$200,000 in $20 bills and four parachutes. </p>
<p>Upon arrival in Seattle, Cooper allowed the other passengers to deplane in exchange for the money and the parachutes. Cooper then ordered the pilot to fly to Mexico but low and slowly – <a href="https://www.biography.com/crime-figure/db-cooper">no higher than 10,000 feet (3,048 meters) and under 200 knots (230 mph, 370 kph)</a>. Somewhere between Seattle and a fuel stop in Reno, Nevada, Cooper and the loot disappeared out the back of the aircraft via the 727’s <a href="https://saverocity.com/taggingmiles/wp-content/uploads/sites/16/2016/07/727-Aft-Stairs.jpg">aft stairwell</a>. No one knows for sure what happened to him, though some of the money was recovered in 1980.</p>
<figure class="align-center ">
<img alt="Decomposed bills arranged in a grid." src="https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=409&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=409&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=409&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=514&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=514&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473058/original/file-20220707-16-ucwl40.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=514&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The serial numbers on these $20 bills found in 1980 matched those given to Cooper in 1971.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-badly-decomposed-20-dollar-bills-were-shown-to-newsmen-news-photo/515123698?adppopup=true">Bettmann/Getty Images</a></span>
</figcaption>
</figure>
<p>Cooper wasn’t the first person to hijack an American airliner and demand money. That dubious honor belongs to <a href="https://content.time.com/time/subscriber/article/0,33009,909374,00.html">Arthur Barkley</a>. Frustrated with his inability to get government officials to take seriously his dispute with the IRS, on June 4, 1970, Barkley hijacked a TWA aircraft, demanding $100 million and a hearing before the U.S. Supreme Court. Barkley’s efforts failed, and he ended up confined to a mental institution. </p>
<p>The idea that Cooper might have succeeded, however, clearly inspired several imitators. While it remains uncertain whether Cooper lived to enjoy the fruits of his escapade, none of his imitators did. They included <a href="https://www.fbi.gov/history/famous-cases/richard-floyd-mccoy-jr">Richard McCoy, Jr.</a>, <a href="https://www.stltoday.com/news/local/metro/article_1aac5de6-6eb4-5245-a126-7adf324d5eb2.html">Martin J. McNally</a> and <a href="https://www.wfmz.com/features/historys-headlines/historys-headlines-skyjack-of-1972/article_940d5703-8e18-528b-80c4-443b3607b6b0.html">Frederick Hahneman</a>, all of whom successfully parachuted out of the aircraft once they received their ransom payments, only to be eventually caught and punished.</p>
<h2>Tightening the screws</h2>
<figure class="align-right ">
<img alt="Man in suit walks with arms and legs handcuffed." src="https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=836&fit=crop&dpr=1 600w, https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=836&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=836&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1051&fit=crop&dpr=1 754w, https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1051&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/473067/original/file-20220707-14-z1nker.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1051&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Four months after D.B. Cooper’s daring extortion, Richard McCoy, Jr. hijacked a plane, received $500,000 and parachuted out of the aircraft. Two days later, he was apprehended.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/newsmen-try-to-elicit-comment-from-accused-hijacker-richard-news-photo/515402276?adppopup=true">Bettmann/Getty Images</a></span>
</figcaption>
</figure>
<p>In response to the spate of more violent and costly hijackings, the U.S. government established the <a href="https://www.ibm.com/blogs/systems/a-brief-history-of-airline-security-hijackings-and-metal-detectors/">first anti-hijacking security protocols</a>. Most of them aimed to prevent hijackers from getting on aircraft in the first place. The measures included a hijacker profile, metal detectors and X-ray machines. Specific to Cooper, airlines retrofitted aircraft with a devise known as a <a href="https://www.wikimotors.org/what-is-a-cooper-vane.htm">Cooper vane</a> that made it impossible to open aft stairwells during flight. </p>
<p>The protocols put in place in the 1970s also laid the foundation for the expansive security measures taken after 9/11. A series of court cases upheld the constitutionality of these early measures. For example, <a href="https://law.justia.com/cases/federal/district-courts/FSupp/328/1077/1428246/">United States v. Lopez</a>, decided in 1971, upheld the use of the hijacker profile. </p>
<p>More importantly, in <a href="https://law.justia.com/cases/federal/appellate-courts/F2/454/769/438142/">United States v. Epperson</a>, a federal court ruled in 1972 that the government’s interest in preventing hijackings justified the requirement for passengers to pass through a magnetometer at the airport. And in 1973, the Ninth Circuit Court, in <a href="https://casetext.com/case/united-states-v-davis-51">United States v. Davis</a>, declared that the government’s need to protect passengers from hijackings rendered all searches of passengers for weapons and explosives as reasonable and legal. </p>
<p>These rulings upholding early anti-hijacking measures helped create <a href="https://www.ojp.gov/ncjrs/virtual-library/abstracts/post-9-11-challenges-aviation-security-homeland-security-law-and">the strong legal grounds</a> for the rapid adoption of the more rigorous security protocols – including detailed identification checks, random pat-downs and full body scans – adopted after 9/11. </p>
<p>The mystery surrounding the fate of Cooper may have afforded him an outsized place in American popular culture, but his crime should also be remembered as one in a consequential wave of hijackings that finally forced the U.S. government, airline executives and airport officials to adopt the first versions of the security measures travelers take for granted today.</p><img src="https://counter.theconversation.com/content/185562/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Janet Bednarek does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>From 1968 to 1974, US airlines experienced 130 hijackings. But it was Cooper’s hijacking-as-extortion plot that captured the public’s imagination – and inspired a copycat crime wave.Janet Bednarek, Professor of History, University of DaytonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1835552022-07-01T10:50:51Z2022-07-01T10:50:51ZHere are the most effective things you can do to fight climate change<figure><img src="https://images.theconversation.com/files/470246/original/file-20220622-14-3m51x5.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C6709%2C4466&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cutting driving and flying are two of the most eco-friendly actions you can take.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/portrait-young-africanamerican-woman-giving-speech-1818952307">Shutterstock</a></span></figcaption></figure><p>Limiting global warming to 1.5°C above pre-industrial levels requires reaching <a href="https://theconversation.com/net-zero-carbon-neutral-carbon-negative-confused-by-all-the-carbon-jargon-then-read-this-151382">net zero</a> emissions by the middle of this century. This means that, in less than three decades, we need to reverse more than a century of rising emissions <em>and</em> bring annual emissions down to near zero, while balancing out all remaining <a href="https://www.cdp.net/en/articles/climate/how-can-companies-handle-so-called-residual-emissions">unavoidable emissions</a> by actively removing carbon from the atmosphere.</p>
<p>To help speed this process as individuals, we’ve got to do everything we can to cut down our use of fossil fuels. But many people <a href="https://www.ipsos.com/en/ipsos-perils-perception-climate-change">aren’t aware</a> of the most effective ways to do this. Thankfully, the <a href="https://theconversation.com/five-key-points-in-the-ipcc-report-on-climate-change-impacts-and-adaptation-178195">latest report</a> by the UN climate change panel <a href="https://www.ipcc.ch/">IPCC</a> devotes a chapter to all the ways in which changes in people’s behaviour can accelerate the transition to net zero.</p>
<p>The chapter includes an analysis of 60 individual actions which can help fight climate change, building on <a href="https://iopscience.iop.org/article/10.1088/1748-9326/ab8589">research</a> led by Diana Ivanova at the University of Leeds – and to which I contributed. We grouped these actions into three areas: avoiding consumption, shifting consumption and improving consumption (making it more efficient). The charts below, produced for the <a href="https://www.ipcc.ch/report/ar6/wg3/">IPCC report</a>, show what we found.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Five charts showing how reducing different activities could cut emissions" src="https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=824&fit=crop&dpr=1 600w, https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=824&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=824&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1036&fit=crop&dpr=1 754w, https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1036&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/470042/original/file-20220621-11-drcbgs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1036&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The first three charts show, in descending order, how effective different behaviours are at cutting emissions.</span>
<span class="attribution"><span class="source">Max Callaghan</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What to avoid</h2>
<p>By far the most effective things to avoid involve transport. Living <a href="https://theconversation.com/car-ownership-is-likely-to-become-a-thing-of-the-past-and-so-could-public-transport-110550">without a car</a> reduces greenhouse gas emissions by an average of 2 tonnes of CO₂ emissions per person per year, while avoiding a single long distance return flight cuts emissions by an average of 1.9 tonnes. That’s equivalent to driving a <a href="https://www.eea.europa.eu/ims/co2-performance-of-new-passenger">typical EU car</a> more than 16,000km from <a href="https://www.google.com/maps/dir/Hamburg/Ulaanbaatar,+Mongolia/@50.3406451,40.6332697,4z/data=!3m1!4b1!4m14!4m13!1m5!1m1!1s0x47b161837e1813b9:0x4263df27bd63aa0!2m2!1d9.9936819!2d53.5510846!1m5!1m1!1s0x5d96925be2b18aab:0xe606927864a1847f!2m2!1d106.9057439!2d47.8863988!3e0">Hamburg, Germany to Ulaanbaatar, Mongolia</a> and back.</p>
<figure class="align-center ">
<img alt="People seated on an aeroplane viewed from the central back aisle" src="https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/470241/original/file-20220622-23-7ds6gj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Taking fewer flights can have a significant impact on your carbon footprint.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/interior-airplane-passengers-on-seats-waiting-256478011">Shutterstock</a></span>
</figcaption>
</figure>
<p>Since the vast majority of the world’s population do not fly at all – and of those who do, only a <a href="https://www.businesstraveller.com/business-travel/2021/03/31/majority-of-flights-taken-by-a-small-percentage-of-flyers/">small percentage</a> fly frequently – fliers can make very substantial reductions to their carbon footprints with each flight they avoid.</p>
<h2>What to shift</h2>
<p>But living sustainably is not just about giving things up. Large reductions in emissions can be achieved by shifting to a different way of doing things. Because driving is so polluting, for example, shifting to <a href="https://theconversation.com/12-best-ways-to-get-cars-out-of-cities-ranked-by-new-research-180642">public transport</a>, walking or cycling can make an enormous change, with <a href="https://theconversation.com/we-transformed-a-london-borough-into-a-game-to-get-fewer-people-travelling-by-car-heres-what-happened-171035">added benefits</a> for your personal health and local air pollution levels.</p>
<p>Likewise, because of the high emissions associated with <a href="https://theconversation.com/meat-eating-is-a-big-climate-issue-but-isnt-getting-the-attention-it-deserves-170855">meat and dairy</a> – particularly those produced by farming sheep and cows – shifting towards more sustainable diets can substantially reduce your carbon footprint. A <a href="https://www.independent.co.uk/life-style/health-and-families/veganism-environmental-impact-planet-reduced-plant-based-diet-humans-study-a8378631.html">totally vegan diet</a> is the most effective way to do this, but sizeable savings can be made simply by <a href="https://theconversation.com/five-ways-the-meat-on-your-plate-is-killing-the-planet-76128">switching</a> from beef and lamb to pork and chicken. </p>
<h2>What to improve</h2>
<p>Finally, the things we do already could be made more efficient by improving <a href="https://theconversation.com/oceans-and-their-largest-inhabitants-could-be-the-key-to-storing-our-carbon-emissions-180901">carbon</a> efficiency at home: for example by using insulation and <a href="https://theconversation.com/no-space-for-a-heat-pump-heres-how-your-whole-street-could-get-off-gas-heating-180005">heat pumps</a>, or producing your own renewable energy by installing <a href="https://theconversation.com/solar-panels-on-half-the-worlds-roofs-could-meet-its-entire-electricity-demand-new-research-169302">solar panels</a>. Switching from a combustion car to an electric one – ideally a battery EV, which generates <a href="https://www.energy.gov/sites/default/files/2014/03/f9/thomas_fcev_vs_battery_evs.pdf">much larger reductions</a> in emissions than hybrid or fuel cell EVs – will make your car journeys more efficient. Plus, its effect on emissions will increase as time goes by and the amount of electricity generated by renewables grows. </p>
<figure class="align-center ">
<img alt="A person in a grey jumper holds a bowl of greens on their lap" src="https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=360&fit=crop&dpr=1 600w, https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=360&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=360&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=452&fit=crop&dpr=1 754w, https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=452&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/470240/original/file-20220622-26-y6ds2e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=452&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Vegan diets are hugely beneficial for the environment.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/healthy-vegetarian-dinner-woman-jeans-warm-1317602774">Shutterstock</a></span>
</figcaption>
</figure>
<p>In the race to net zero, <a href="https://theconversation.com/climate-breakdown-even-if-we-miss-the-1-5-c-target-we-must-still-fight-to-prevent-every-single-increment-of-warming-178581">every tonne of CO₂</a> really does count. If more of us take even a few of these suggestions into account, we’re collectively more likely to be able to achieve the ambitious goals set out in the <a href="https://theconversation.com/the-paris-agreement-is-working-as-intended-but-weve-still-got-a-long-way-to-go-173478">Paris climate agreement</a>. Of course, these changes will need to be backed by major political action on sustainability at the same time. </p>
<p>If we’re to use less fossil fuel energy, the use of fossil fuels needs to be either restricted or made more expensive. The social consequences of this need to be carefully managed so that <a href="https://carbonpricingdashboard.worldbank.org/what-carbon-pricing">carbon pricing schemes</a> can benefit people on lower incomes: which can happen if <a href="https://www.mcc-berlin.net/en/research/policy-briefs/taxreform.html">revenues are redistributed</a> to take the financial burden off poorer households. </p>
<p>But there’s a whole lot more that governments could do to help people to live more sustainably, such as providing better, safer public transport and “<a href="https://theconversation.com/from-walking-to-cycling-how-we-get-around-a-city-is-a-gender-equality-issue-new-research-175014">active travel</a>” infrastructure (such as bike lanes and pedestrian zones) so that people have alternatives to driving and flying. </p>
<p>There’s no avoiding the fact that if political solutions are to address climate change with the urgency our global situation requires, these solutions will limit the extent to which we can indulge in carbon-intensive behaviours. More than anything, we must vote into power those prepared to make such tough decisions for the sake of our planet’s future.</p>
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<p class="fine-print"><em><span>Max Callaghan does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Our research shows the best changes individuals can make to cut carbon emissions and reduce the effects of climate change.Max Callaghan, PhD Student, University of LeedsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1761942022-03-14T12:20:05Z2022-03-14T12:20:05ZWhy do flocks of birds swoop and swirl together in the sky? A biologist explains the science of murmurations<figure><img src="https://images.theconversation.com/files/450675/original/file-20220308-21-1nhx7v8.jpg?ixlib=rb-1.1.0&rect=325%2C135%2C4196%2C2542&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Murmurations can have as many as 750,000 birds flying in unison.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/murmuration-of-starlings-royalty-free-image/481428151">mikedabell/iStock via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
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<blockquote>
<p><strong>Why do flocks of birds swoop and swirl together in the sky? – Artie W., age 9, Astoria, New York</strong></p>
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<p>A shape-shifting flock of thousands of starlings, called a murmuration, is amazing to see. As many as 750,000 birds join together in flight. The birds spread out and come together. The flock splits apart and fuses together again. Murmurations constantly change direction, flying up a few hundred meters, then zooming down to almost crash to the ground. <a href="https://www.worldphoto.org/blogs/10-05-18/these-are-most-amazing-photos-starling-murmurations">They look like swirling blobs</a>, making teardrops, figure eights, columns and other shapes. A murmuration can move fast – starlings fly up to 50 miles per hour (80 kilometers per hour).</p>
<p>The <a href="https://birdsoftheworld.org/bow/species/eursta/cur/introduction">European or common starling</a>, like many birds, forms groups called flocks when foraging for food or migrating. But a murmuration is different. This special kind of flock is named for the sound of a low murmur it makes from thousands of wingbeats and soft flight calls.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/V4f_1_r80RY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">‘Flight of the Starlings’ by Jan van IJken was shot in the Netherlands; the audio lets you hear how a murmuration gets its name.</span></figcaption>
</figure>
<p>Murmurations form about an hour before sunset in fall, winter and early spring, when the birds are near where they’ll sleep. After maybe 45 minutes of this spectacular aerial display, the birds all at once drop down into their roost for the night.</p>
<h2>Why do starlings form murmurations?</h2>
<p><a href="https://theconversation.com/how-do-geese-know-how-to-fly-south-for-the-winter-149225">Unlike the V formations of migrating geese</a>, murmurations provide no aerodynamic advantage.</p>
<p>Scientists think a murmuration is a <a href="https://www.cell.com/current-biology/pdf/S0960-9822(11)01315-7.pdf">visual invitation to attract other starlings</a> to join a group night roost. One theory is that spending the night together <a href="https://doi.org/10.1371/journal.pone.0179277">keeps the starlings warmer</a> as they share their body heat. It might also reduce the chance an individual bird would be eaten overnight by a predator such as an owl or <a href="https://animalia.bio/american-marten">marten</a>.</p>
<p>This dilution effect might be part of the reason murmurations happen: The more starlings in the flock, the lower the risk to any one bird of being the one that gets snagged by a predator. Predators are more likely to catch the nearest prey, so the swirling of a murmuration could happen as individual birds try to move toward the safer middle of the crowd. Scientists call this the <a href="https://doi.org/10.1093/beheco/arq157">selfish herd effect</a>. </p>
<p>Of course, the more birds in a flock, the more eyes and ears to detect the predator before it’s too late.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/iRNqhi2ka9k?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">‘Murmuration’ by Sophie Windsor Clive & Liberty Smith.</span></figcaption>
</figure>
<p>And a gigantic mass of whirling, swirling birds can make it <a href="https://doi.org/10.1007/s00265-018-2609-0">hard to focus on a single target</a>. A falcon or hawk can get <a href="https://doi.org/10.1016/j.anbehav.2011.07.006">confused and distracted by tricky wave patterns</a> in the murmuration’s movements. It also must be careful not to collide with the flock and get hurt. </p>
<p>Over <a href="https://doi.org/10.1371/journal.pone.0179277">3,000 citizen scientist volunteers reported spotting murmurations</a> in a recent study. A third of them saw a raptor attack the murmuration. That observation suggests that murmurations do form to help protect the birds from predators – but it’s also possible a huge murmuration would be what attracted a hawk, for instance, in the first place. </p>
<h2>How do starlings coordinate their behavior?</h2>
<p>Murmurations have no leader and follow no plan. Instead, scientists believe movements are coordinated by starlings observing what others around them are doing. Birds in the middle can <a href="https://doi.org/10.1073/pnas.1402202111">see through the flock on all sides</a> to its edge and beyond. Somehow they keep track of how the flock is moving as a whole and adjust accordingly. </p>
<p>To learn what’s happening inside murmurations, <a href="https://doi.org/10.1016/j.anbehav.2008.02.004">some researchers film them</a> using many cameras at the same time. Then they use computer programs to track the movements of individual starlings and create 3D models of the flock.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="equally spaced group of birds flying against blue sky" src="https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/450678/original/file-20220308-13-l69vf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Within the murmuration, individual birds aren’t tightly packed together.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/murmuration-of-european-starlings-in-flight-across-royalty-free-image/1368050180">K C Bailey/iStock via Getty Images</a></span>
</figcaption>
</figure>
<p>The videos reveal that the birds are not as densely packed as they might appear from the ground; there is room to maneuver. Starlings are closer to their side neighbors than those in front or behind. Starlings on the edge frequently move deeper into the flock.</p>
<p>Mathematicians and computer scientists try to <a href="https://doi.org/10.1007/s00285-021-01675-2">create virtual murmurations using rules</a> that birds might follow in a flock – like moving in the same direction as their neighbor, staying close and not colliding. From these simulations, it seems that <a href="https://doi.org/10.1093/beheco/arq149">each bird must keep track of seven neighbors</a> and adjust based on what they’re doing to keep the murmuration from falling apart in a chaotic mess. And they do all this while flying as fast as they can.</p>
<p>Large schools of fish can appear to behave like murmurations, as do groups of some swarming insects, including honeybees. All these synchronized movements can happen so fast within flocks, herds, swarms and schools that some scientists <a href="https://doi.org/10.1016/j.tics.2018.08.001">once thought it required animal ESP</a>!</p>
<p>Biologists, mathematicians, physicists, computer scientists and engineers are all working to figure out how animals carry out these displays. Curiosity drives this research, of course. But it may also have practical applications too, like helping develop autonomous vehicles that can travel in tight formation and work in coordinated groups without colliding.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/176194/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tom Langen does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>These coordinated movements of a flock of starlings follow no plan or leader. Scientists used to think the animals must communicate via ESP to create these fast-moving blobs.Tom Langen, Professor of Biology, Clarkson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1711842021-11-05T14:12:35Z2021-11-05T14:12:35ZReducing air travel by small amounts each year could level off the climate impact<figure><img src="https://images.theconversation.com/files/430219/original/file-20211104-27-q5x093.jpg?ixlib=rb-1.1.0&rect=1%2C1%2C1276%2C848&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Aviation is a significant contributor to global greenhouse gas emissions.</span> <span class="attribution"><a class="source" href="https://pixabay.com/photos/airport-travelers-persons-business-731196/">Free-Photos/Pixabay</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Just before the pandemic, aircraft engines were burning <a href="https://www.iata.org/en/iata-repository/pressroom/fact-sheets/industry-statistics/">one billion litres</a> of fuel a day. But then the number of daily civil aviation flights fell from <a href="https://www.iata.org/en/iata-repository/pressroom/fact-sheets/industry-statistics/">110,000</a> to less than 50,000 during 2020, on average. With the easing of travel restrictions, air traffic is increasing back towards its pre-pandemic peak.</p>
<p>Most world leaders and delegates will have flown to Glasgow to attend COP26 – the 26th annual UN climate change summit – in person. But as they haggle over emissions targets to limit global warming to 1.5°C, and not <a href="https://theconversation.com/cop26-what-would-the-world-be-like-at-3-c-of-warming-and-how-would-it-be-different-from-1-5-c-171030">3°C or more</a>, aviation is unlikely to be included in them, given the lack of low-carbon alternatives to long-haul flights.</p>
<p>But it should be. <a href="https://iopscience.iop.org/article/10.1088/1748-9326/ac286e">In new research</a>, my colleagues and I calculated that if the aviation sector continues to grow on its present trajectory, its jet fuel consumption will have added 0.1˚C to global warming by 2050 – half of it to date, the other half in the next three decades. </p>
<p>Aviation is responsible for 4% of the 1.2°C rise in the global mean temperature we have already experienced since the industrial revolution. Without action to reduce flights, the sector will account for 17% of the remaining 0.3°C left in the 1.5°C temperature target, and 6% of the 0.8°C left to stay within 2°C. Airlines effectively add more to global warming <a href="http://globalcarbonatlas.org/en/CO2-emissions">than most countries.</a></p>
<h2>Warming footprints</h2>
<p>At the current rate, the world will have warmed by 2°C <a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM_final.pdf">within three decades</a>. To quantify how different activities contribute to warming, scientists measure carbon emissions. This is because how much the Earth warms is proportional to cumulative carbon emissions in the atmosphere. This is a very good approximation in many cases, but it is inaccurate for emissions caused by aeroplanes travelling at altitudes of up to 12 kilometres.</p>
<p>As well as CO₂, aircraft engines emit nitrogen oxides, water vapour, sulphur and soot, causing <a href="https://www.nature.com/articles/s41467-018-04068-0">contrail cirrus clouds</a> and other complicated chemical reactions in the atmosphere. The sum of these so-called non-CO₂ effects adds more warming on top of the CO₂ emissions. So the total warming footprint of aviation is between two and three times higher than a conventional carbon footprint.</p>
<figure class="align-center ">
<img alt="An aeroplane's trail viewed from between two tall buildings" src="https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/430221/original/file-20211104-21-xa7pet.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Condensation trails produced by aircraft engines contribute to global warming.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/architecture-skyscraper-skyline-3984725/">MichaelGaida/Pixabay</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>While a large share of a flight’s CO₂ emissions remain in the atmosphere for many thousands of years, the non-CO₂ effects diminish over time, <a href="https://doi.org/10.1016/j.atmosenv.2020.117834">vanishing within about ten years</a>. So any growth in aviation, measured in global jet fuel consumption, has an amplified impact as both CO₂ and non-CO₂ effects add up. </p>
<p>But a decline in aviation can partly reverse some warming, as the non-CO₂ effects disappear over time until only the CO₂ effects remain. Think of the non-CO₂ effects like a bathtub – it fills up when the taps are turned further and further, despite a slow outflow down the plughole. But the same bathtub will eventually empty if the taps are gradually turned down.</p>
<p>The non-CO₂ effects of flights on the atmosphere will slowly disappear if fewer and fewer flights are taken, so that aviation’s contribution to warming eventually levels off. In that situation, the increase from continued CO₂ emissions would balance the fall in non-CO₂ effects, and although aviation would still contribute to climate change, the total warming from both would remain constant over time. How much would aviation need to shrink to level off its influence on global warming? </p>
<p>Our calculations show that flying does not need to stop immediately to prevent aviation’s contribution to global warming expanding. Flying has already caused 0.04°C of warming to date. But with a yearly decrease of 2.5% in jet fuel consumption, currently only achievable with cuts in air traffic, this warming will level off at a constant level over the coming decades.</p>
<h2>When do we really need to fly?</h2>
<p>COVID-19 had a huge impact on the aviation sector. Air traffic is still approximately 10-20% below pre-pandemic levels, but is <a href="https://doi.org/10.1088/1748-9326/ac286e">rebounding quickly</a>. Politicians should shift subsidies from flying to more sustainable modes of transport, such as train journeys. And there is much more that can be done.</p>
<figure class="align-center ">
<img alt="An aeroplane parked at an airport" src="https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/430217/original/file-20211104-25-1v0sxdb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Forced changes in flying habits due to the pandemic have led some to permanently cut back on flights.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/airplane-aircraft-airport-travel-4885803/">Dmncwndrlch/Pixabay</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Lockdowns and the shift to remote working made many people rethink the necessity of flying. People resolving to fly less can contribute considerably to reducing the number of unnecessary flights. Combining in-person and virtual attendance in hybrid meetings wherever possible is a great way to support that shift.</p>
<p>Reducing the space that business classes take on aeroplanes is another way to cut the number of flights, as it allows more passengers to travel on one flight. </p>
<p>Not allowing airport expansions could also have a big impact. The UK’s Climate Change Committee, an expert body which advises the UK government, has recommended <a href="https://www.theccc.org.uk/wp-content/uploads/2020/12/Sector-summary-Aviation.pdf">not expanding airports</a> to align the sector with climate targets. Yet the expansion of Heathrow airport is currently <a href="https://www.bbc.co.uk/news/explainers-51646562">planned to go ahead</a>.</p>
<p>Sustainable aviation fuels, and hydrogen or electric planes, are being developed, but none of these technologies are currently available at the necessary scale. At the moment, there is little chance of the aviation industry meeting any climate targets if it aims for a return to its pre-pandemic rate of growth.</p>
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<img alt="COP26: the world's biggest climate talks" src="https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/424739/original/file-20211005-17-cgrf2z.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong>This story is part of The Conversation’s coverage on COP26, the Glasgow climate conference, by experts from around the world.</strong>
<br><em>Amid a rising tide of climate news and stories, The Conversation is here to clear the air and make sure you get information you can trust. <a href="https://page.theconversation.com/cop26-glasgow-2021-climate-change-summit/"><strong>More.</strong></a></em> </p>
<hr><img src="https://counter.theconversation.com/content/171184/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Milan Klöwer receives funding from the UK's Natural Environmental Research Council, the Copernicus Programme of the European Commission and the European Research Council.</span></em></p>Reducing jet fuel consumption by 2.5% each year could halt aviation’s growing influence on climate change.Milan Klöwer, Postdoctoral Researcher in Weather and Climate Modelling, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1660822021-09-02T12:23:09Z2021-09-02T12:23:09ZAn entire generation of Americans has no idea how easy air travel used to be<figure><img src="https://images.theconversation.com/files/418911/original/file-20210901-19-1k3wxe6.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C6016%2C3998&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Airplane passengers line up for TSA security screenings at Denver International Airport in 2019.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/airplane-passengers-line-up-for-tsa-security-screenings-at-news-photo/1159430281?adppopup=true">Robert Alexander/Getty Images</a></span></figcaption></figure><p>During the mid-1990s I traveled between Dayton, Ohio, and Washington, D.C., twice a month during the school year as half of a commuting couple. I could leave Dayton by 5:15 p.m., drive nearly 80 miles to the Columbus airport during rush hour, park my car in the economy lot, and still get to my gate in plenty of time for a 7:30 p.m. departure. </p>
<p>Then 9/11 happened.</p>
<p>The terrorist attacks brought swift and lasting changes to the air travel experience in the United States. And after more than 20 years of ever-more-elaborate airport security protocols, many air travelers have no knowledge of – or only vague memories of – what air travel was like before 9/11. </p>
<p>As someone <a href="https://udayton.edu/directory/artssciences/history/bednarek_janet.php">who has studied the history of airports in the United States</a> – and someone old enough to remember air travel before 9/11 – I find it striking, on the one hand, how reluctant the federal government, the airlines, and airports were to adopt early security measures. </p>
<p>On the other hand, it’s been jarring to watch how abruptly the sprawling <a href="https://www.dhs.gov/transportation-security-overview">Transportation Security Agency system</a> was created – and how quickly American air travelers came to accept those security measures as both normal and seemingly permanent features of all U.S. airports.</p>
<h2>Security Kabuki</h2>
<p>In the early decades of air travel, airport security – beyond basic policing – <a href="https://www.sun-sentinel.com/news/fl-xpm-2011-09-10-fl-security-then-and-now-20110910-story.html">was essentially nonexistent</a>. Getting on a plane was no different from getting on a bus or train.</p>
<p>But in the late 1960s and early 1970s, there was a wave of hijackings, terrorist attacks and extortion attempts – the most infamous being that of the man known as <a href="https://www.fbi.gov/history/famous-cases/db-cooper-hijacking">D.B. Cooper</a>, who commandeered a Boeing 727, demanded US$200,000 and, upon securing the case, dramatically parachuted from the plane, never to be found.</p>
<figure class="align-right ">
<img alt="Man with tie, sunglasses and pursed lips." src="https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=867&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=867&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=867&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1089&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1089&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418912/original/file-20210901-17-5wdgzd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1089&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">A sketch of suspected hijacker D.B. Cooper, whose dramatic hijacking prompted calls for enhanced security.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-fbi-released-11-27-this-artists-drawing-of-d-b-cooper-news-photo/515418618?adppopup=true">Bettmann/Getty Images</a></span>
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<p><a href="https://www.latimes.com/archives/la-xpm-2011-jun-12-la-tr-airline-safety-timeline-20110612-story.html">Attacks on U.S. flights usually prompted another new security measure</a>, whether it was the formation of the air marshal program, which placed armed federal agents on U.S. commercial aircraft; the development of a hijacker profile, aimed at identifying people deemed likely to threaten an aircraft; or the screening of all passengers.</p>
<p>By 1973, under the new protocols, <a href="https://www.latimes.com/archives/la-xpm-2011-jun-12-la-tr-airline-safety-timeline-20110612-story.html">air travelers had</a> to pass through a metal detector and have any bags X-rayed to check for weapons or suspicious objects.</p>
<p>For the most part, however, these measures were intended to reassure nervous flyers – <a href="http://www.aviationfacts.eu/uploads/thema/file_en/58f65f0b70726f5be9020000/Security_US_after_9-11_Fact_sheet.pdf">security theater</a> that sought to minimally impede easy passage from check-in to gate. For domestic travel, it was possible to arrive at the airport terminal 20 to 30 minutes before your flight <a href="https://www.cntraveler.com/story/what-airports-were-like-in-1987">and still be able to reach the gate in time to board</a>. Families and friends <a href="https://www.usatoday.com/story/travel/roadwarriorvoices/2016/03/16/flying-in-the-1980s/81817754/">could easily accompany a traveler</a> to their gate for take-off and meet them at the gate upon their return. </p>
<p>Above all, airlines didn’t want to inconvenience passengers, and airports were <a href="https://www.cntraveler.com/story/what-airports-were-like-in-1987">reluctant to lose the extra revenue</a> from family and friends who might frequent airport restaurants, bars and shops when dropping off or picking up those passengers.</p>
<p>In addition, these security measures, though called for by the Federal Aviation Administration, were the responsibility of not the federal government, but the airlines. And to keep costs down, the airlines tended to contract private companies to conduct security screenings <a href="https://www.cntraveler.com/story/how-airport-security-has-changed-since-september-11">that used minimally trained low-paid employees</a>.</p>
<h2>The clampdown</h2>
<p>All that changed with the 9/11 terrorist attacks.</p>
<p>Once the airlines returned to the skies on Sept. 14, 2001, it was immediately apparent that flying was going to be different. Passengers arriving at airports were greeted by armed military personnel, as governors throughout the country <a href="http://www.cnn.com/2001/US/11/09/rec.bush.airportsecurity/index.html">had mobilized the National Guard to protect the nation’s airports</a>. They remained on patrol for several months.</p>
<p>Security measures only increased in December 2001, when Richard Reid, the so-called “Shoe Bomber,” attempted to <a href="https://www.fbi.gov/history/artifact-of-the-month/december-2020-richard-reids-shoes">set off explosives in his shoes</a> on an international flight from Paris to Miami. Taking off your shoes before passing through security quickly became a requirement. </p>
<figure class="align-center ">
<img alt="Barefoot woman stands next to her luggage." src="https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=324&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=324&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=324&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=407&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=407&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418919/original/file-20210901-17-1petico.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=407&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Removing shoes became one of many added security measures.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-feet-of-a-barefoot-traveler-are-seen-with-her-luggage-news-photo/2203634?adppopup=true">Tim Boyle/Getty Images</a></span>
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<p>Then, in 2006, British officials intercepted an attempt to carry liquid explosives aboard a flight, resulting in a ban on all liquids. This was later modified to restricting passengers to liquids of <a href="https://www.latimes.com/archives/la-xpm-2011-jun-12-la-tr-airline-safety-timeline-20110612-story.html">no more than 3.4 ounces</a>. By 2010, <a href="https://www.latimes.com/archives/la-xpm-2011-jun-12-la-tr-airline-safety-timeline-20110612-story.html">the full-body scanner</a> had become a familiar sight at airports throughout the U.S.</p>
<p><a href="https://www.statista.com/chart/19056/average-and-peak-waiting-time-at-tsa-security-screening/">A 2019 study</a> indicated that the average time to get through security at some of the nation’s busiest airports varied from just over 23 minutes at Newark Liberty to 16.3 minutes at Seattle-Tacoma, but could go as high as 60 minutes and 34 minutes, respectively, at those same two airports during peak times.</p>
<p>These new security measures became the responsibility of the federal government to enforce. In November 2001, Congress created the <a href="https://www.tsa.gov/sites/default/files/aviation_and_transportation_security_act_atsa_public_law_107_1771.pdf">Transportation Security Agency</a>, and by the early months of 2002, their employees had become the face of transportation security throughout the United States – at airports as well as railroads, subways and other forms of transportation. </p>
<p>Today, the TSA employs <a href="https://www.tsatestprep.com/tsa-hiring-process/">over 50,000 agents</a>.</p>
<p>[<em>Over 110,000 readers rely on The Conversation’s newsletter to understand the world.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=100Ksignup">Sign up today</a>.]</p>
<h2>No end in sight</h2>
<p>In the first decade after 9/11, the federal government <a href="https://www.scirp.org/journal/paperinformation.aspx?paperid=102057">spent over $62 billion on airport security</a> in total, as annual spending for the TSA increased from $4.34 billion in 2002 to $7.23 billion in 2011, and <a href="https://www.dhs.gov/sites/default/files/publications/dhs_bib_-_web_version_-_final_508.pdf">has only grown since then</a>.</p>
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<img alt="An arm patch featuring an eagle and an American flag." src="https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=925&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=925&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=925&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1163&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1163&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418915/original/file-20210901-23-13606vm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1163&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The Transportation Security Administration was created in the wake of the 9/11 terrorist attacks.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/armpatch-for-the-transportation-security-administration-new-news-photo/563534711?adppopup=true">Bryan Chan/Los Angeles Times via Getty Images</a></span>
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<p>In many ways, the post-9/11 scramble by airport officials to address security concerns was similar to the impulse to address public health concerns <a href="https://www.forbes.com/sites/suzannerowankelleher/2020/06/18/the-future-of-airport-design-after-covid-19-according-to-an-airport-architect/?sh=5c35c5053919">in the wake of the COVID-19 pandemic</a>, when plastic barriers, hand sanitizers and floor markings encouraging social distancing appeared at airports throughout the U.S. </p>
<p>How long the COVID-19 measures will need to stay in place remains to be seen. However, the security measures adopted after 9/11 have proved permanent enough that they have become incorporated into recent airport terminal renovations. </p>
<p>For example, when Reagan National Airport’s new terminal opened in 1997, passengers could move freely between <a href="https://www.washingtonpost.com/local/trafficandcommuting/work-moves-forward-on-a-new-concourse-at-reagan-national-airport/2019/12/30/65235d8a-1dd1-11ea-8d58-5ac3600967a1_story.html">the shop- and restaurant-filled National Hall and the gates in Terminals B and C</a>. After 9/11, airport officials placed security checkpoints at the entrances to Terminals B and C, effectively making shops and restaurants no longer accessible to passengers who had passed through security.</p>
<p>Now, <a href="https://www.flyreagan.com/travel-information/construction-project/new-security-checkpoints">the almost-completed $1 billion redesign</a> will move the security checkpoints to a new building constructed above the airport’s roadway and open up access among National Hall, Terminals B and C and a new commuter terminal. </p>
<p>Nearly a generation has passed since the terrorist attacks of 9/11. Even those of us old enough to remember air travel before that fateful date have grown accustomed to the new normal. And while passengers today might quite happily mark the eventual end of the COVID-19 public health security measures, they’re far less likely to see a return to pre-9/11 security levels at the airport anytime soon.</p><img src="https://counter.theconversation.com/content/166082/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Janet Bednarek does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Since 9/11, billions have been spent beefing up airport security. Was it worth it?Janet Bednarek, Professor of History, University of DaytonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1590102021-04-28T14:15:21Z2021-04-28T14:15:21ZShort-haul flight ban is a good start – now we need to reimagine the modern airport<p>If your journey takes two and a half hours or less by train, then <a href="https://www.theguardian.com/business/2021/apr/12/france-ban-some-domestic-flights-train-available-macron-climate-convention-mps">no flights are allowed</a>. That’s the idea recently approved by the French national assembly as a strategy for reining in the aviation sector’s greenhouse gas emissions.</p>
<p>Now the fine print. Connecting flights are exempt and, in practice, only five routes within France are likely to be affected, mainly from the secondary airport of Paris-Orly (ORY). About <a href="https://www.theguardian.com/commentisfree/2021/apr/13/france-ban-short-domestic-flights-britain-air-travel">12% of France’s domestic flights</a> will be curtailed, but most of the network will remain intact.</p>
<p>Flights <a href="https://www.eurocontrol.int/publication/eurocontrol-data-snapshot-co2-emissions-flight-distance">shorter than 500 km</a> contributed less than 4% of the EU’s total emissions from aviation in 2019, despite making up one-quarter of all European flights. Meanwhile, 6% of EU flights travelled 4,000 km or further in 2020 but produced more than half of EU-wide emissions from flying. Short-haul flights are far less efficient than long-haul ones because a large portion of an aircraft’s fuel is burned during take-off. So cutting them where possible <a href="https://www.sciencedirect.com/science/article/pii/S0959652619310455">makes sense</a>, even if the overall effect on emissions is small. </p>
<p>But banning short-haul flights is important for another reason: it marks one of the first times that politicians in a wealthy country have endorsed something that most, if not all, have been reluctant even to consider. That high-carbon conveniences aren’t always necessary, or even desirable, and that curbs on the most polluting aspects of consumption are necessary to tackle climate change.</p>
<h2>Slower but greener</h2>
<p>Until now, most of the initiatives for making air transport sustainable have focused on making aeroplanes <a href="https://www.eurocontrol.int/sites/default/files/2021-04/eurocontrol-think-paper-10-perfect-green-flight.pdf">more energy efficient</a> or <a href="https://www.theguardian.com/environment/2021/mar/23/sweden-to-increase-airport-fees-for-high-polluting-planes">penalising high-polluting flights</a>. </p>
<p>These approaches, along with the <a href="https://www.iata.org/en/programs/environment/sustainable-aviation-fuels/">use of sustainable fuels</a>, might gradually lower emissions on long-haul routes with no possible substitution. But for shorter journeys with multiple travel options, <a href="https://www.researchgate.net/profile/Sara-Mingorria/publication/340931513_Degrowth_of_aviation/links/5ea577e5299bf1125610463f/Degrowth-of-aviation.pdf">some academics argue</a> that a cultural change is necessary. One that promotes lower consumption and greater sufficiency over speed and convenience and raises the question of whether alternative ways of travel that leave a lighter footprint could suffice.</p>
<p>Research suggests that encouraging such a transformation in attitudes might be effective. <a href="https://www.sciencedirect.com/science/article/abs/pii/S1361920916302371">An Australian study</a> showed that scrapping air journeys in favour of high-speed rail travel between Sydney and Melbourne would reduce CO₂ emissions by 18% over three decades – and that includes emissions from developing and maintaining the entire rail infrastructure.</p>
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Read more:
<a href="https://theconversation.com/plane-train-or-automobile-the-climate-impact-of-transport-is-surprisingly-complicated-117350">Plane, train, or automobile? The climate impact of transport is surprisingly complicated</a>
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<p>In Finland, a recent <a href="https://www.sciencedirect.com/science/article/pii/S2213624X20300663">analysis</a> suggested that replacing all national short-haul flights with train travel could reduce CO₂ emissions in these trips by 95%. Even travelling by car or bus for similar distances is <a href="https://www.sciencedirect.com/science/article/pii/S0959652619310455">better for the planet</a> than hopping on a plane. </p>
<h2>Connecting flights</h2>
<p>Convincing people to ditch short-distance travel by air might be a tough sell though. As the French proposals highlight, most short-haul flights carry connecting passengers between airline <a href="https://www.sciencedirect.com/science/article/abs/pii/0966692394900477">hubs</a>, which opens up more options for worldwide travel, particularly for people living in more remote places.</p>
<p>As passengers, we know that even if we <a href="https://doi.org/10.1177%2F0361198106195100104">miss our connecting flight</a>, the airline is obliged to book us a seat on the next plane. If we decide to make the connection by rail, that burden falls on us. People often buy flexi-tickets or consider long times between connections, meaning more waiting and higher costs, which overall make rail alternatives less appealing. A solution could be integrated ticketing across all modes of transport, ensuring connections are automatically rebooked, whether by land or sky.</p>
<figure class="align-center ">
<img alt="A cartoon of a man sat with a suitcase under an airport departures board." src="https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=339&fit=crop&dpr=1 600w, https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=339&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=339&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=426&fit=crop&dpr=1 754w, https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=426&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/397589/original/file-20210428-21-r9pdy3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=426&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">People can spend hours, and even days, waiting in airports for connecting flights.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/passenger-waiting-plane-boarding-delays-strikes-1011713659">Naeblys/Shutterstock</a></span>
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</figure>
<p>This idea is already taking off. Some airlines, including <a href="https://www.airfrance.us/US/en/common/resainfovol/avion_train/reservation_avion_train_bruxelles_airfrance.htm">AirFrance</a>, offer passengers combined air and rail tickets. <a href="https://www.railtech.com/infrastructure/2021/03/10/deutsche-bahn-and-lufthansa-launch-new-joint-offers/">Lufthansa is working with Deutsche Bahn</a> to replace flights with trains for national connections. <a href="https://elpais.com/tecnologia/digitalizacion/2021-04-16/la-aplicacion-que-unira-y-simplificara-nuestros-viajes.html">Renfe</a>, the national rail provider in Spain, is also working towards an integrated service which could include short air segments alongside longer train journeys. In the UK, <a href="https://www.businesstraveller.com/features/connecting-low-cost-airlines-gatwick/">Gatwick Connects</a> - rolled out at London Gatwick airport in 2015 - simplified connections between low-cost airlines, automatically rebooking passengers if needed. A similar concept could be used with ground connections to the airport.</p>
<p>If the goal is to eliminate short-haul flights altogether, simply having a rail station next to the airport is not good enough. It’s time to <a href="https://www-sciencedirect-com.uow.idm.oclc.org/science/article/pii/S0967070X06000187">reimagine airports</a> as fully connected hubs seamlessly linking ground and air travel – providing integrated tickets, smooth (but longer) ground-based connections, and a coordinated air-ground transport system.</p><img src="https://counter.theconversation.com/content/159010/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Luis Delgado receives funding from H2020-SESAR-2019-2 project Modus - grant agreement n° 891166.</span></em></p><p class="fine-print"><em><span>Enrica Papa does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Banning short-haul flights should be just the first step on the path to greener transport systems.Enrica Papa, Reader in Transport Planning, University of WestminsterLuis Delgado, Senior Research Fellow on Air Transport, University of WestminsterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1511802021-01-25T13:29:51Z2021-01-25T13:29:51ZWhy does it take longer to fly from east to west on an airplane?<figure><img src="https://images.theconversation.com/files/378155/original/file-20210111-17-hrdaro.jpg?ixlib=rb-1.1.0&rect=0%2C50%2C1533%2C970&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The jet stream can have a big impact on how long a plane ride will last.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?title=Special:Search&limit=500&offset=500&profile=default&search=boeing+747&advancedSearch-current=%7B%7D&ns0=1&ns6=1&ns12=1&ns14=1&ns100=1&ns106=1&searchToken=6ddmgacgqvctsdphhxwo6ty0n#%2Fmedia%2FFile%3AG-CIVA_Boeing_747_British_Airways_%288401802240%29.jpg">Aeroprints via Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>Why does it take longer to fly from east to west on an airplane? – Henry D, Age 7, Cambridge, Massachusetts</strong></p>
</blockquote>
<hr>
<p>I am a retired <a href="https://www.unomaha.edu/college-of-public-affairs-and-community-service/aviation/about-us/faculty-staff/skip-bailey.php">United States Air Force pilot and flight instructor</a>, and a few years ago I was sitting in the cockpit of a Boeing 747 airplane. I was 29,000 feet in the sky, flying from New Jersey to Sacramento, California, and then to Hawaii. It took six hours to fly and land the plane safely in Sacramento. After a few hours in California, I continued to Hawaii,which took almost another five hours of flying. That was 11 total hours of flying. </p>
<p>After enjoying the sunshine in Hawaii, it was time to fly back to New Jersey. This trip went much faster. I didn’t stop in California this time, but flying back only took about eight and a half hours. I was still flying the same airplane, and New Jersey wasn’t any closer to California or Hawaii than it had been a few days before. </p>
<p>So why was my flight to Hawaii, from east to west, so much longer than my flight home?</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graphic showing the rough locations of jet streams around the globe." src="https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=345&fit=crop&dpr=1 600w, https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=345&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=345&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=433&fit=crop&dpr=1 754w, https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=433&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/378134/original/file-20210111-13-mc63ul.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=433&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Jet streams always blow from west to east and can found in many places around the world.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Jet_stream#/media/File:Jetstreamconfig.jpg">Lyndon State College Meteorology via Wikipedia</a></span>
</figcaption>
</figure>
<h2>Riding on a river of air</h2>
<p>The reason it took so much longer to fly back is the <a href="https://en.wikipedia.org/wiki/Jet_stream">jet stream</a>, a river of fast-moving air high up in the sky. </p>
<p>Jet streams are usually about 100 miles wide. They can be thousands of miles long and are found all over the earth. To be called a jet stream, the wind must be moving faster than 60 mph. </p>
<p>Jet streams generally blow from the west to the east around the Earth, often <a href="https://doi.org/10.1029/2008GL033614">following a meandering, curved path</a> just like a river on land. The jet stream over the United States never stays in one place – it tends to move <a href="https://doi.org/10.1175/1520-0469(1961)018%3C0172:TSJSOW%3E2.0.CO;2">farther south and blow stronger in the winter</a>, and to move farther north and not blow as strong in the summer. </p>
<p>So what does this have to do with planes?</p>
<h2>Flying into the wind</h2>
<p>Airplane pilots measure speed in two different ways. First is airspeed – how fast the wind would feel if you stuck your hand out the window. The second is ground speed – how fast the plane is moving over the ground. When you fly in the jet stream, your airspeed always stays the same, but your ground speed can change a lot because the air around the plane is moving.</p>
<p>On the way to Hawaii, I was flying with an airspeed of 562 mph. But because the jet stream was blowing against my airplane – called a headwind – at 140 mph, I was actually only moving across the ground at 422 mph.</p>
<p>But flying from Hawaii to New Jersey, the jet stream blows from behind the plane and pushes it forward. I was still flying with an airspeed of 562 mph, but the 140 mph tailwind meant that my airplane was moving across the ground at 702 mph.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graphic showing how routes differ when a plan flies from east to west or west to east." src="https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=275&fit=crop&dpr=1 600w, https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=275&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=275&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=346&fit=crop&dpr=1 754w, https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=346&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/378135/original/file-20210111-15-4p9wus.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=346&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Planes will try to avoid the jet stream when flying east to west, but try to hitch a ride on the way back.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Jet_stream#/media/File:Greatcircle_Jetstream_routes.svg">ChaosNil via Wikipedia</a></span>
</figcaption>
</figure>
<h2>Pilots plan to go fast</h2>
<p>When pilots plan the route of their flights, they often use weather forecasts <a href="https://doi.org/10.1175/1520-0493(1981)109%3C2450:COTWPJ%3E2.0.CO;2">to find where the jet stream is blowing</a>. When they fly from the east to the west, they try <a href="https://simpleflying.com/why-aircraft-dont-fly-in-a-straight-line-from-origin-to-destination/">to plan their flight</a> so the jet stream isn’t blowing against their airplane and giving them a bad headwind. When they plan their flight from the west to the east, they look for the jet stream and try to fly so it can give them a big tailwind and help them fly faster. A good plan can help conserve fuel too.</p>
<p>The next time you are flying high across the country from east to west, don’t be surprised when it takes a little longer than you expect. But be excited knowing that when you fly back your pilot is probably hitching a ride along the jet stream to get you home fast.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/151180/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Skip Bailey does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>When planes fly from east to west, they are flying against a river of air called a jet stream. These air currents can make your flight longer or shorter, depending on which way you are going.Skip Bailey, Aviation Institute Flight Training Coordinator and Instructor, University of Nebraska OmahaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1441492020-11-16T20:04:25Z2020-11-16T20:04:25ZHow to plan successful e-conferences during and after the COVID-19 pandemic<figure><img src="https://images.theconversation.com/files/369176/original/file-20201112-19-1dq25ud.jpg?ixlib=rb-1.1.0&rect=44%2C0%2C7304%2C3448&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Exploring the unique capacities of online events, instead of trying to replicate in-person conventions, will yield the best results. </span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Many professionals, including academics, are accustomed to flying a lot. Or they were before <a href="https://www.bbc.com/future/article/20200709-how-covid-19-will-change-air-travel-as-we-know-it">COVID-19 drastically reduced air travel</a> and disrupted conference plans globally. For now, the mingling of many people in hotel conference rooms, flown in from many places, isn’t an option.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/canadians-are-less-willing-to-fly-during-covid-19-than-americans-144995">Canadians are less willing to fly during COVID-19 than Americans</a>
</strong>
</em>
</p>
<hr>
<p>Conferences are increasingly <a href="https://www.nature.com/articles/d41586-020-01489-0">being organized online</a>. What this should look like and what changes it implies for the nature of professional networks and knowledge-sharing remains to be seen. </p>
<p>But <a href="https://www.openbookpublishers.com/product/1178">smart design choices</a> can translate into significant gains in the sustainability, accessibility and the insights people can gain from conferences in the COVID-19 era and beyond. </p>
<p>Online conferencing provides new opportunities to broaden conversations and invite more inclusive feedback. Our work is interested in how <a href="https://www.estsjournal.org/index.php/ests/article/view/363/223">low-carbon research practices</a> can be good for the planet and good for research outcomes. </p>
<h2>Costs of travelling</h2>
<p>Being and working together, particularly in smaller workshop settings, is an invaluable way to generate new ideas and connections in many fields and professional settings. But older models of gathering, particularly in their scale and carbon intensity, have drawbacks that we can no longer afford to ignore.</p>
<p>Flying was a fraught proposition before the pandemic. Air travel contributes to <a href="https://stay-grounded.org/airport-conflicts-struggles-for-environmental-justice-webinar-summary/">environmental injustices</a> in communities located near airports and on the front lines of <a href="https://www.versobooks.com/books/2901-mobility-justice">climate change</a>. </p>
<p>Travel requirements also exclude many from participation, whether it’s due to <a href="https://www.theguardian.com/higher-education-network/2017/aug/30/expensive-academic-conferences-give-us-old-ideas-and-no-new-faces">high costs</a>, <a href="https://www.insidehighered.com/news/2019/03/28/scholars-complain-visa-problems-ahead-international-conference-canada">border restrictions</a>, accessibility challenges or pressures on participants with <a href="https://slate.com/human-interest/2015/09/academic-conferences-and-on-site-child-care-an-academic-speaks-out-on-a-long-standing-lack.html">care responsibilities</a>. Not everyone can travel. Certainly, not everyone should. Many of us, particularly in the Global North, need to travel much less.</p>
<p>Planes aside, both in universities <a href="https://www.zdnet.com/article/coronavirus-will-end-tech-conferences-and-events-as-we-know-them/">and beyond</a>, some people are <a href="https://www.insidehighered.com/news/2017/07/25/article-sparks-new-round-criticism-costs-associated-academic-conferences">increasingly wondering</a> if conference conventions are serving them well. </p>
<p>Is a brief talk within a marathon of other presentations really worth it? Are there other ways to gather that might do more for knowledge-sharing and the planet?</p>
<figure class="align-center ">
<img alt="The Los Angeles skyline seen on a smartphone." src="https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369177/original/file-20201112-23-15pn0lh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Foregoing travel may seem unglamourous, but virtual conference attendees can benefit from creative multimedia sharing.</span>
<span class="attribution"><span class="source">(Jakub Gorajek/Unsplash)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>New models, new possibilities</h2>
<p>The good news is there’s no need to reinvent the wheel. Researchers attuned to the environmental and equity challenges of flying have been experimenting with alternative formats for years. </p>
<p>The <a href="https://hiltner.english.ucsb.edu/index.php/ncnc-guide/">Nearly Carbon Neutral Conference</a>, run by <a href="https://hiltner.english.ucsb.edu/index.php/26-2/#:%7E:text=Ken%20Hiltner%20is%20a%20professor,Fellow%2C%20including%20the%20Bowdoin%20Prize.">professor of environmental humanities Ken Hiltner</a> at the University of California Santa Barbara, is one example. The conference hosts video talks on YouTube and WordPress — a format that dramatically lowers participation costs. </p>
<p><a href="https://distribute.utoronto.ca/playbook/">The Society for Cultural Anthropology and the Society for Visual Anthropology</a> offer another model: their joint biennial conference runs as an eight-hour loop of video content, broadcast to international nodes with supports available to participants in the Global South. Both formats boast strong registration numbers, significant reach and improved accessibility standards.</p>
<p>Other gains are possible through more experimental approaches. A workshop we organized earlier this year, <a href="https://energyandplace.artsrn.ualberta.ca/">Energy In/Out of Place</a>, succeeded in connecting five research teams and more than 100 attendees, all without registration fees. Presenters shared multimedia projects and highlighted inventive ways of producing work for digital distribution.</p>
<p>These and other examples suggest that we have opportunities to redesign and repurpose conferences to reduce carbon emissions and improve knowledge-sharing. This will require an approach to event planning that does not seek merely to replicate in-person conventions, but to explore the unique capacities of online events.</p>
<h2>Make the most of going online</h2>
<p>Here are three ways to yield the benefits of going online.</p>
<p><strong><em>1. Plan written feedback for richer sessions.</em></strong></p>
<p>Conventional academic conference panels offer limited time for feedback: typically less than five minutes per paper. This time can easily be eaten up by questions that, as speakers often note, “are more of a comment, actually.” </p>
<p>Online events can be designed to emphasize written feedback — via synchronous chat or asynchronous comment threads — ensuring more varied and coherent responses than on-the-spot verbal remarks. Attendees routinely comment that this is a major selling point of e-conferences.</p>
<p><strong><em>2. Plan for accessibility from the start.</em></strong></p>
<p>Disabled designers and advocates have long used digital tools to meet and work remotely. We should learn from <a href="https://www.mapping-access.com/blog-1/2020/3/10/accessible-teaching-in-the-time-of-covid-19">disability culture’s technologies, protocols and best practices</a> to make online gatherings more accessible than traditional conferences ever were. If your conference didn’t include image descriptions, captions and translations before, it certainly can now.</p>
<p>Better access can also boost diversity. Lower fees mean more under-represented scholars or attendees can get in the virtual room. E-conference organizers might also use funding earmarked for travel expenses to fund research and the creation of new media to share research directly, as we did with the conference we planned.</p>
<p><strong><em>3. Make creative use of new presentation formats.</em></strong></p>
<p>E-conferences’ heavily mediated nature has the potential to rewrite the conventional, and often monotonous, Powerpoint presentation. Ranging from small gestures (like recording a talk from a field site) to grand ones (like composing video essays), e-conferences can use the capacities of digital media for inquiry and expression. Such an approach dovetails with <a href="https://thepedagogicalimpulse.com/research-methodologies/">research-creation</a>, a framework that challenges researchers to articulate their arguments in accessible or esthetically engaging ways.</p>
<h2>The work ahead</h2>
<figure class="align-right ">
<img alt="A woman sits with a laptop in a videoconference." src="https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=901&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=901&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=901&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1132&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1132&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369178/original/file-20201112-21-w1dr6e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1132&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Capturing the creative energy of in-person gatherings is challenging but not insurmountabe.</span>
<span class="attribution"><span class="source">(UK Black Tech)</span></span>
</figcaption>
</figure>
<p>Pursuing these benefits doesn’t mean they’re guaranteed, nor will these efforts come without hazards. </p>
<p>Digital distractions, energy-intensive streaming, security risks, entanglement with <a href="https://www.theguardian.com/technology/2019/jan/20/shoshana-zuboff-age-of-surveillance-capitalism-google-facebook">surveillance capitalism</a> and capturing the creative energy of in-person gatherings are all difficulties faced by e-conference organizers. </p>
<p>They’re significant, but not insurmountable. We’ve recently written a <a href="https://www.energyhumanities.ca/news/making-and-meeting-online">short, accessible report</a> highlighting several ways to meet these challenges. This is a road we build by walking.</p>
<p>All in all, the disruptions of COVID-19 present an opportunity to rethink how we do conferences and workshops: to ask what they are for, who they benefit and how we can improve them, hopefully in ways that permanently reduce the amount of travel we do in a post-pandemic world.</p><img src="https://counter.theconversation.com/content/144149/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anne Pasek receives funding from the Canada Research Chairs Program.</span></em></p><p class="fine-print"><em><span>Caleb Wellum and Emily Roehl do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Academics and others concerned with benefitting from peer professional collaboration can use COVID-19 disruptions as an opportunity to improve conferences through smart design.Caleb Wellum, Energy Futures Postdoctoral Fellow, University of AlbertaAnne Pasek, Assistant Professor and Canada Research Chair in Media, Culture, and the Environment, Trent UniversityEmily Roehl, Lecturer, Honors College, Texas State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1492252020-11-16T13:21:46Z2020-11-16T13:21:46ZHow do geese know how to fly south for the winter?<figure><img src="https://images.theconversation.com/files/369377/original/file-20201113-13-7fvj1e.jpg?ixlib=rb-1.1.0&rect=1218%2C0%2C3624%2C2488&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Geese fly day or night, depending on when conditions are best.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/migrating-canada-geese-royalty-free-image/108309781">sharply_done/E+ via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>How do geese know how to fly south for the winter? – Oscar V., age 9, Huntington, New York</strong></p>
</blockquote>
<hr>
<p>To be ready to migrate in the fall, geese start preparing in midsummer. Babies born in the spring are mostly grown up by then. Adult geese <a href="https://doi.org/10.2307/1369611">grow a new set of plumage</a> after shedding their old feathers – a <a href="https://doi.org/10.1007/978-1-4613-0425-8_6">process called molting</a>.</p>
<p>They need flight and body feathers to be in good condition for the long flight ahead, and to insulate their bodies from the winter cold. For a few weeks during this process, geese can’t fly at all, and they stay out on the water to avoid predators.</p>
<p>Geese have a clock in their brain that <a href="https://www.americanscientist.org/article/avian-migration-the-ultimate-red-eye-flight">measures how much sunlight there is each day</a>. The days grow shorter during the late summer and early fall, and that’s how geese know it’s time to get ready for the journey south. Families join together in larger flocks. Geese gorge on grains and grasses to fatten up in preparation for their journey.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="two geese tails emerge from water as they look for food" src="https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=442&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=442&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=442&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=555&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=555&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369378/original/file-20201113-19-z06ost.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=555&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Geese fattening up by eating some underwater foods.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/two-canada-geese-searching-for-food-royalty-free-image/1282657623">Jennifer Yakey-Ault/iStock via Getty Images</a></span>
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<h2>When it’s time to go</h2>
<p>There are two different types of bird migration. For most bird species that migrate from temperate climates to the tropics in winter, <a href="https://doi.org/10.1016/j.tree.2011.07.009">migration is instinctual</a>. These birds, such as swallows, orioles and warblers, leave their northern breeding place before weather turns harsh and food becomes scarce.</p>
<p>Most migrate at night, individually rather than in flocks, and they know where to go and how to get there without guidance from parents or other birds. They migrate continuously, except for short stopovers to fuel up on insects, fruit, or seeds before continuing on their way. </p>
<p>Canada geese and other migratory geese species are different. They usually remain in their summer range until the weather is cold, water starts to freeze, and food gets hard to come by. <a href="https://doi.org/10.1111/oik.03121">Once conditions become so tough</a> that they can’t find enough to eat, geese migrate.</p>
<p>Maybe you’ve observed flock members signaling they’re ready to go: <a href="https://doi.org/10.2307/4083454">They honk loudly and point their bills toward the sky</a>. Single families of geese, or flocks of several families together, take off and head south. Flocks join with other flocks. Geese fly by day or night, depending on factors like weather conditions or brightness of the moon.</p>
<p><a href="https://www.jstor.org/stable/4161751">Geese navigate based on experience</a>, using landmarks including rivers, coastlines and mountain ranges. They may also use celestial cues such as the sun and stars. Geese have a physical compass in their head that allows them to <a href="https://doi.org/10.1641/B570207">tell north and south by detecting the Earth’s magnetic field</a>.</p>
<p>Young geese learn the migration route and landmarks by following their parents and other experienced geese. People who have raised and socially bonded with geese have even taught the birds new migration routes by leading them in an ultralight aircraft – as in the movie “<a href="https://www.imdb.com/title/tt0116329/">Fly Away Home</a>.”</p>
<p>[<em><a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=experts">Expertise in your inbox. Sign up for The Conversation’s newsletter and get expert takes on today’s news, every day.</a></em>]</p>
<h2>On their way</h2>
<p>Geese are heavy birds, and they fly fast – over 30 miles per hour – using powerful wing beats, rather than gliding like eagles or vultures. All this flapping for a heavy bird <a href="https://doi.org/10.1111/j.0908-8857.2004.03378.x">takes a lot of energy</a>. Geese work very hard during migration flights. To reduce the effort, geese fly at night when the <a href="https://www.jstor.org/stable/4161751">air is calmer, or in the day when there’s a helpful tailwind</a>; they avoid flying into a headwind that would blow them backward.</p>
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<a href="https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="geese fly in a V against a clear sky" src="https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369379/original/file-20201113-15-xo4vqf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The different wing positions of these greylag geese show their flapping motion, with the individual at the tip of the V working the hardest.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/flock-of-greylag-geese-in-the-sky-royalty-free-image/461948687">Anagramm/iStock via Getty Images</a></span>
</figcaption>
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<p>In addition, they have another energy-saving trick. To reduce drag and to receive a little extra lift, geese fly close behind and about one wing length to the side of the one immediately in front. When all flock members do this, the familiar V shape appears.</p>
<p>This <a href="https://doi.org/10.1016/0022-5193(83)90110-8">form of drafting, also called vortex surfing</a>, saves a lot of energy. Following another bird at the right distance blocks any headwind. The flapping of the bird ahead creates a forward movement of air called a slipstream, which helps pull the trailing bird forward. And little pockets of spinning air, called vortices, produce lift that helps keep a trailing bird aloft. The same physics explains why fighter jets fly in V formation to conserve fuel.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-bkxG28OUZw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">This video explains some of the physics of how the V formation helps keep geese up in the sky for less energy.</span></figcaption>
</figure>
<p>The bird at the point of the V, in the front of the flock, gets no advantage from drafting. It is working much harder than the others. When it gets too tired, it drops back and another takes the lead. Recently, ornithologists have discovered that when families migrate together as a flock, the <a href="https://doi.org/10.1111/jav.02392">parents take turns at the tip of the V</a>. The younger geese, which are not as strong, line up along the V behind the lead parent.</p>
<p>Most geese that breed in a particular region will migrate along similar routes, <a href="https://www.ducks.org/conservation/waterfowl-research-science/understanding-waterfowl-the-flyways">called flyways</a>. For example, geese that pass by my house in Northern New York follow the Atlantic flyway. They’ll end up on the Atlantic Coast and migrate south following the shoreline.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="three Canada geese fly over sand dunes" src="https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=414&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=414&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=414&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369380/original/file-20201113-15-1k8iqp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Many geese head to the coast and then navigate south along the shoreline.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/canada-geese-over-sand-dunes-at-jones-beach-long-royalty-free-image/639801946">Vicki Jauron, Babylon and Beyond Photography/Moment via Getty Images</a></span>
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<p>Rather than migrate nonstop to their wintering grounds, many geese travel in stages, pausing at traditional stopover sites to rest and regain lost fat. Geese from the <a href="https://www.allaboutbirds.org/guide/Canada_Goose/lifehistory">most northern populations travel to the farthest south</a>. More southerly breeding populations don’t migrate as far. This is called leapfrog migration, since the northern geese literally fly over the more southern birds. <a href="https://doi.org/10.2307/3676124">Why this happens is a bit of a mystery</a>, but it’s possible the northern breeders continue further south to avoid competing for food with southern geese that have already found good wintering conditions closer to their summer homes.</p>
<p>Because geese learn migratory routes, they can flexibly adjust where <a href="https://doi.org/10.1111/gcb.14061">they go as conditions change</a>. Goose migration stopover sites and wintering grounds have shifted, for example, because of changes in farming practices, availability of lawns and golf courses, and other changes in land use. Migratory geese are now adjusting when and where they migrate <a href="https://doi.org/10.3389/fevo.2019.00502">as a consequence of global climate change</a>. And some groups of Canada geese have decided <a href="https://doi.org/10.1675/063.034.0403">to just stay put and skip the migration altogether</a>.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/149225/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tom Langen does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Geese honk loudly and point their bills toward the sky when they’re ready to start the migration. Here’s how they know it’s time, how they navigate and how they conserve energy on the grueling trip.Tom Langen, Professor of Biology, Clarkson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1449952020-09-08T15:44:17Z2020-09-08T15:44:17ZCanadians are less willing to fly during COVID-19 than Americans<figure><img src="https://images.theconversation.com/files/356575/original/file-20200904-24-k2j3gv.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3594%2C2365&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A woman walks through Pearson International Airport in Toronto at the onset of the COVID-19 pandemic in March 2020.</span> <span class="attribution"><span class="source">THE CANADIAN PRESS/Nathan Denette</span></span></figcaption></figure><p>The International Air Transport Association, known as the IATA — the body representing the air transport industry — expects <a href="https://www.iata.org/en/pressroom/pr/2020-07-28-02/">global air passenger traffic to fall 55 per cent in 2020 compared to 2019, and global passenger traffic not to return to pre-pandemic levels until 2024.</a> </p>
<p>This steep decline follows <a href="https://www.statista.com/statistics/278372/revenue-of-commercial-airlines-worldwide/">10 years of a compound annual growth rate of 5.3 per cent</a>, <a href="https://www.iata.org/en/pressroom/pr/2020-06-09-01/">resulting in a US$838 billion air travel industry by 2019.</a> </p>
<p>The collapse in consumer demand has been driven by the COVID-19 pandemic and government measures to control it, largely by closing international borders and locking countries down.</p>
<p>Until the end of January 2020, global seat capacity was pretty much on track to produce another record year with 109 million seats on scheduled services. However, as the virus spread from Asia to Europe and then North America, airlines rapidly removed capacity. By early May, there were only around 30 million seats, mostly for <a href="https://www.iata.org/en/pressroom/pr/2020-07-28-02/">domestic flights</a>. Not until early June did we see the first real <a href="https://www.oag.com/blog/oag-coronavirus-update-week-twenty-four">increase in capacity</a>.</p>
<p>However, seat capacity does not equal demand, and airlines continue to make an unprecedented number of schedule changes, including delaying and cancelling flights at the last minute to the frustration of passengers still flying. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/airlines-should-rethink-their-refusal-to-refund-passengers-during-covid-19-140380">Airlines should rethink their refusal to refund passengers during COVID-19</a>
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<hr>
<h2>Canadians don’t want to fly</h2>
<p>Where China and Europe have progressively put capacity back to entice travellers to fly domestically or regionally, this has not really been the case for Canada or the United States. <a href="https://researchco.ca/2020/07/31/usa-canada-travel/">A recent poll</a> showed that less than a third of Canadians are willing to fly anywhere, and only 17 per cent would fly to the U.S. </p>
<p>Americans are more inclined to fly, with 35 per cent willing to do so domestically and 28 per cent willing to fly to Canada.</p>
<p>Citizens of both countries had the exact same information regarding the spread of COVID-19, so it’s interesting to see how differently each country’s travellers reacted. The differences in how each country dealt early on with the pandemic have had a lasting impact, as quick early responses resulted in slower, more controlled spreads of COVID-19. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/6-countries-6-curves-how-nations-that-moved-fast-against-covid-19-avoided-disaster-137333">6 countries, 6 curves: how nations that moved fast against COVID-19 avoided disaster</a>
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<h2>Severity of COVID-19</h2>
<p>This divergence in consumer confidence in flying can be partially explained by the severity of the COVID-19 outbreak: with more than six million cases and 558 deaths per million inhabitants, <a href="https://www.statista.com/statistics/1104709/coronavirus-deaths-worldwide-per-million-inhabitants/">the United States compares extremely unfavourably</a> to Canada’s 127,940 cases and 247 deaths per million inhabitants. It’s understandable why Canadians are reluctant to travel to the U.S. </p>
<p>The difference in consumer attitudes between Canadians and Americans becomes quite clear when we compare arrivals at Toronto Pearson International Airport — <a href="https://www.airport-technology.com/news/covid-19-canada-international-flights/">one of only four airports in Canada authorized to receive international flights</a>. Officially, <a href="https://www.cbc.ca/news/business/canada-u-s-border-travel-couples-alaska-1.5670867">the border was closed to most Americans as of March 21</a>, and the federal government still discourages non-essential travel for Canadians, but that doesn’t mean air traffic has stopped completely. </p>
<figure class="align-center ">
<img alt="A Sunwing passenger plane prepares to land." src="https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356983/original/file-20200908-14-1sxlvqs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A Sunwing plane lands at Pearson airport in August 2017. Only about 130 planes are arriving at Toronto’s Pearson airport each day, compared to an average of 650 a day in 2019.</span>
<span class="attribution"><span class="source">THE CANADIAN PRESS/Christopher Katsarov</span></span>
</figcaption>
</figure>
<p>In the midst of the pandemic, between <a href="https://www.torontopearson.com/en/corporate/media">120 and 140 planes arrive daily</a> at Pearson compared to an average of 650 per day in 2019. Incoming international travellers must quarantine for 14 days, and the government of Canada has stated that “<a href="https://www.canada.ca/en/immigration-refugees-citizenship/services/coronavirus-covid19/travel-restrictions-exemptions.html">a foreign national is prohibited from entering Canada from the United States if they seek to enter for an optional or discretionary purpose, such as tourism, recreation or entertainment.</a>”</p>
<p>Although tickets booked directly with airlines are a closely kept secret, IATA reports the number sold through online platforms and travel agents, which represent roughly a third of all tickets sold. </p>
<p>From this, we can see that during January, arrival volumes in general tracked slightly below those of 2019 for both countries, but February saw the start of a steep decline in Canada while the number of arriving Americans continued to increase.</p>
<p>Following the sharp decrease in March and April, arrivals to the United States from Canada bottomed out in May at 16 per cent of 2019 arrivals. Conversely, the number of American travellers arriving in Toronto, although lower than 2019, increased in March over February before declining dramatically in June, when it hit 8.6 per cent of 2019 numbers, before seeing an encouraging increase in July.</p>
<h2>Prices drop</h2>
<p>A number of factors are likely contributing to this improved consumer confidence: while the first two months of 2020 saw year-over-year increases in the average fare paid and March held steady at 2019 levels, the decrease in average fare price since April has been quite dramatic.</p>
<p>Airlines have also <a href="https://globalnews.ca/news/6986751/rebook-cancel-flight-airlines-canada/">relaxed their flight modification and cancellation policies</a>, even for discount economy seating, resulting in 95 per cent of tickets being sold in this class. But people are also realistic about the uncertainties created by COVID-19, and the booking window has dropped to 24 days from 35 days at the beginning of the year. This figure was provided by Tahmor Ghumman, CEO of Spreedix Analytics, in collaboration with IATA.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/air-canadas-cancellation-of-regional-flights-will-gut-remote-communities-143985">Air Canada's cancellation of regional flights will gut remote communities</a>
</strong>
</em>
</p>
<hr>
<p>With consumer confidence slowly returning, the focus is on how to create a travel environment that is not only safe but also perceived to be safe. <a href="https://tc.canada.ca/en/initiatives/covid-19-measures-updates-guidance-issued-transport-canada/canada-s-flight-plan-navigating-covid-19">Transport Canada has established measures to protect travellers,</a> and <a href="https://theconversation.com/how-covid-19-could-impact-travel-for-years-to-come-142971">comparisons to the flight safety challenges that airlines faced after 9/11 are often drawn</a>. </p>
<p>The uncertainty created by lockdowns and quarantines, sometimes imposed on <a href="https://www.theguardian.com/world/2020/jul/25/uk-holidaymakers-returning-from-spain-to-face-quarantine">very short notice</a>, means that consumer confidence is fragile. </p>
<p>With infections periodically spiking in different countries, airlines are forced to cancel flights without warning, which weakens consumer confidence anew. The COVID-19 pandemic therefore is continuing to leave the global air travel industry in a precarious position.</p>
<p><em>Tahmor Ghumman, CEO of Spreedix Analytics, provided data for this article in collaboration with IATA.</em></p><img src="https://counter.theconversation.com/content/144995/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Citizens of the United States and Canada have both had the exact same information regarding the spread of COVID-19, but their attitudes about flying are very different.Marion Joppe, Professor, Law and Economics of Tourism, University of GuelphLianne Foti, Assistant Professor, Gordon S. Lang School of Business and Economics, University of GuelphLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1426542020-07-22T03:35:02Z2020-07-22T03:35:02ZCurious Kids: why can’t humans grow wings?<figure><img src="https://images.theconversation.com/files/348561/original/file-20200721-29-unkkvw.jpg?ixlib=rb-1.1.0&rect=38%2C96%2C4254%2C2761&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><blockquote>
<p><strong>Why can’t humans grow wings? Christina, age 9, Beijing, China.</strong></p>
</blockquote>
<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
<p>Hi Christina! Great question.</p>
<p>Humans are animals that have backbones. This means we’re in a group called “<a href="https://www.britannica.com/animal/vertebrate">vertebrates</a>” – along with fish, amphibians (such as frogs), reptiles, birds and mammals. </p>
<p>A long time ago, humans weren’t around. We actually came from 500-million-year-old <a href="https://nhpbs.org/wild/agnatha.asp">fish</a> that had no arms, legs or jaws. But slowly, from one fish parent to the next, they changed. Some started to grow arms and legs, eventually leading to humans as they are today. </p>
<p>These very slow changes happen to all animals over millions of years, in a process we call evolution. Every part of the human body, and every other animal, evolved in this way.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-how-do-scientists-know-evolution-is-real-122039">Curious Kids: how do scientists know evolution is real?</a>
</strong>
</em>
</p>
<hr>
<h2>Two arms, two legs: a basic vertebrate body plan</h2>
<p>Fish were the first vertebrates to have pairs of limbs. For humans, these are our arms and legs. Fish have pairs of fins at their front and back. </p>
<p>A long time ago, some fish <a href="https://theconversation.com/when-fish-gave-us-the-finger-this-ancient-four-limbed-fish-reveals-the-origins-of-the-human-hand-129072">evolved bones</a> in their fins that would later become human fingers. This pattern of having pairs of two limbs (four in total) resulted in the bodies vertebrates have today. </p>
<p>All vertebrates today have the same body plan: two arms, two legs, a head with two eyes, two nostrils, a mouth with teeth, and so on. </p>
<p>However over the course of evolution, some animals didn’t quite follow this plan exactly. Their bodies needed to be different to suit their lifestyle – whether this was swimming or flying. This is how wings came about.</p>
<h2>How animals started to fly</h2>
<p>Wings of flying vertebrates, such as birds, are simply modified arms that help them fly. </p>
<p>You may have heard of pterosaurs – the (<a href="https://www.nationalgeographic.com/magazine/2017/11/pterosaurs-weirdest-wonders-on-wings/">sometimes huge</a>) flying creatures that lived at the time as dinosaurs. Pterosaurs also slowly formed their wings over many, many years. They did this by growing one long finger connecting a thin layer of skin called a membrane to the rest of their body. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348565/original/file-20200721-21-m6pqb4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Pterosaurs weren’t dinosaurs – rather, they were flying reptiles.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>One group of <a href="https://www.nhm.ac.uk/discover/how-dinosaurs-evolved-into-birds.html">dinosaurs evolved into birds</a> about 160 million years ago. </p>
<p>This happened well after dinosaurs first gained feathers to help keep their bodies cool or warm as needed. Then, from one parent to the next, they slowly gained longer front arms to eventually make wings. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348569/original/file-20200721-25-y9pn94.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">One extinct dinosaur called archaeopteryx looked a bit like a dinosaur, and a bit like bird too. It is often pointed to as an evolutionary link between today’s birds and extinct feathered dinosaurs.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Why didn’t humans evolve to have wings?</h2>
<p>Now let’s look at why humans can’t grow wings. </p>
<p>All living things, including vertebrates, have genes. These are like little instruction booklets inside our bodies that decide how we grow and what our bodies can do. We can’t change what our genes do. For example, your genes are the reason your eyes may be black, or brown, or blue – but you can’t control this.</p>
<p>We also have genes called “<a href="http://encyclopedia.kids.net.au/page/ho/Hox_gene">hox genes</a>”. These make sure our bodies grow a certain way as we get older. For instance, while you might grow taller thank your siblings, hox genes make sure you only grow two arms and two legs – and not eight legs like a spider. In fact, a spider’s own hox genes are what give it eight legs.</p>
<p>So one main reason humans can’t grow wings is because our genes only let us grow arms and legs.</p>
<h2>What if we did have wings though?</h2>
<p>Even if humans did have wings, we wouldn’t immediately be able to fly.</p>
<p>To fly, we would also need the right body size and metabolism. Metabolism is our body’s ability to use fuel (such as from the food we eat) to make energy, which helps us move.</p>
<p>Birds have very higher metabolisms than us. A hummingbird’s heart can beat up to 1,200 times per minute, while a human athlete’s heart might only go as fast as 220 beats per minute. This means hummingbirds can burn energy better than humans.</p>
<p>Flying birds also have much lighter bones that help them <a href="https://www.discovery.com/nature/Why-Do-Birds-Have-Hollow-Bones">breathe better</a>, feathers that help lift them while flying, and powerful <a href="https://www.birdwatchingdaily.com/news/science/eldon-greij-describes-amazing-way-birds-breathe/">lungs</a> that keep oxygen pumping through their bodies.</p>
<p>Unless humans had all of this, we wouldn’t be able to fly even if we did have wings. Dinosaurs also only evolved to become birds by making their bodies much smaller and lighter over time.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-are-humans-going-to-evolve-again-116990">Curious Kids: are humans going to evolve again?</a>
</strong>
</em>
</p>
<hr>
<h2>What about dragons?</h2>
<p>While we know dragons aren’t real, some imaginary dragons have bodies close to real-life vertebrates.</p>
<p>Dragons such as Smaug in the movie The Hobbit have wings and legs only. So if Smaug was real he might actually have been able to fly, as long as he was light, had a high metabolism and a membrane to form his wings. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=318&fit=crop&dpr=1 600w, https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=318&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=318&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=400&fit=crop&dpr=1 754w, https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=400&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/348572/original/file-20200721-23-bau9h6.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=400&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">If Smaug the dragon was real, he may have been able to fly! (Lucky he’s not).</span>
<span class="attribution"><span class="source">Warner Bros</span></span>
</figcaption>
</figure>
<p>On the other hand, the dragon Night Fury from How to Train Your Dragon has arms, legs <em>and</em> wings. In real life, this would be like having two legs and two pairs of arms. </p>
<p>Night Fury breaks the basic rules of evolution as no vertebrate has ever evolved to have this combination of arms and legs. Insects can, but they don’t have backbones so they’re not vertebrates. </p>
<p>So if Night Fury was real, scientists may have to call him an insect.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=317&fit=crop&dpr=1 600w, https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=317&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=317&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=399&fit=crop&dpr=1 754w, https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=399&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/347543/original/file-20200715-33-185c8vi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=399&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Night Fury from How to Train Your Dragon is a very likeable, but not a very realistic character.</span>
<span class="attribution"><span class="source">DreamWorks Animation/IMDB</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/142654/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Long receives funding from The Australian Research Council.</span></em></p>Human genes are one of the main reasons we can’t grow wings. And even if humans did have wings, they wouldn’t necessarily allow us to fly.John Long, Strategic Professor in Palaeontology, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1278002020-02-16T18:57:03Z2020-02-16T18:57:03ZMajor airlines say they’re acting on climate change. Our research reveals how little they’ve achieved<p>If you’re a traveller who cares about reducing your carbon footprint, are some airlines better to fly with than others?</p>
<p>Several of the world’s major airlines have announced plans to become “carbon neutral”, while others are trialling new aviation fuels. But are any of their climate initiatives making much difference?</p>
<p>Those were the questions we set out to answer a year ago, by analysing what the world’s largest 58 airlines – which fly 70% of the total <a href="https://airlinegeeks.com/2015/12/28/airline-metrics-available-seat-kilometers/">available seat-kilometres</a> – are doing to live up to their promises to cut their climate impact.</p>
<p>The good news? Some airlines are taking positive steps. The bad news? When you compare what’s being done against the continued growth in emissions, even the best airlines are not doing anywhere near enough.</p>
<h2>More efficient flights still drive up emissions</h2>
<p><a href="https://amadeus.com/en/insights/white-paper/airline-initiatives-to-reduce-climate-impact">Our research</a> found three-quarters of the world’s biggest airlines showed improvements in carbon efficiency – measured as carbon dioxide per available seat. But that’s not the same as cutting emissions <em>overall</em>.</p>
<p>One good example was the Spanish flag carrier Iberia, which reduced emissions per seat by about 6% in 2017, but increased absolute emissions by 7%.</p>
<hr>
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<p>For 2018, compared with 2017, the collective impact of all the climate measures being undertaken by the 58 biggest airlines amounted to an improvement of 1%. This falls short of the industry’s goal of achieving a <a href="https://www.iata.org/en/policy/environment/climate-change/">1.5% increase</a> in efficiency. And the improvements were more than wiped out by the industry’s overall 5.2% annual increase in emissions. </p>
<p>This challenge is even clearer when you look slightly further back. <a href="https://www.iata.org/en/iata-repository/pressroom/fact-sheets/fact-sheet---industry-statistics/">Industry figures</a> show global airlines produced 733 million tonnes of CO₂ emissions in 2014. Falling fares and more people around wanting to fly saw airline emissions rise 23% in just five years. </p>
<h2>What are the airlines doing?</h2>
<p>Airlines reported climate initiatives across 22 areas, with the most common involving fleet renewal, engine efficiency, weight reductions and flight path optimisation. Examples in <a href="https://amadeus.com/en/insights/white-paper/airline-initiatives-to-reduce-climate-impact">our paper</a> include:</p>
<ul>
<li>Singapore Airlines modified the Trent 900 engines on their A380 aircraft, saving 26,326 tonnes of CO₂ (equivalent to 0.24% of the airline’s annual emissions);</li>
<li>KLM’s efforts to reduce weight on board led to a CO₂ reduction of 13,500 tonnes (0.05% of KLM’s emissions).</li>
<li>Etihad reports savings of 17,000 tonnes of CO₂ due to flight plan improvements (0.16% of its emissions). </li>
</ul>
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<p>Nineteen of the 58 large airlines I examined invest in alternative fuels. But the scale of their research and development programs, and use of alternative fuels, remains tiny.</p>
<p>As an example, for Earth Day 2018 <a href="https://aircanada.mediaroom.com/2018-04-19-Air-Canada-to-Save-160-Tonnes-of-Carbon-on-Earth-Day-through-Innovative-Biojet-Fuel-Project-at-Toronto-Pearson-Airport">Air Canada announced</a> a 160-tonne emissions saving from blending 230,000 litres of “biojet” fuel into 22 domestic flights. How much fuel was that? Not even enough to fill the more than 300,000-litre capacity of just one A380 plane.</p>
<h2>Carbon neutral promises</h2>
<p>Some airlines, including Qantas, are aiming to be <a href="https://www.qantasnewsroom.com.au/media-releases/qantas-group-to-slash-carbon-emissions/">carbon neutral by 2050</a>. While that won’t be easy, Qantas is at least starting with better climate reporting; it’s one of only <a href="https://www.fsb-tcfd.org/tcfd-supporters/">eight airlines</a> addressing its carbon risk through the systematic <a href="https://www.fsb-tcfd.org/">Task Force on Climate-related Financial Disclosures</a> process. </p>
<p>About half of the major airlines engage in carbon offsetting, but only 13 provide information on measurable impacts. Theses include Air New Zealand, with its FlyNeutral program to help restore native forest in New Zealand. </p>
<p>That lack of detail means the integrity of many offset schemes is questionable. And even if properly managed, offsets <a href="https://theconversation.com/flying-home-for-christmas-carbon-offsets-are-important-but-they-wont-fix-plane-pollution-89148">still avoid</a> the fact that we can’t make <a href="https://www.sciencedirect.com/science/article/abs/pii/S0969699716302538">deep carbon cuts</a> if we keep flying at current rates.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/flight-shame-wont-fix-airline-emissions-we-need-a-smarter-solution-127257">Flight shame won't fix airline emissions. We need a smarter solution</a>
</strong>
</em>
</p>
<hr>
<h2>What airlines and governments need to do</h2>
<p>Our research shows major airlines’ climate efforts are achieving nowhere near enough. To decrease aviation emissions, three major changes are urgently needed. </p>
<ol>
<li><p>All airlines need to implement all measures across the 22 categories covered in <a href="https://amadeus.com/en/insights/white-paper/airline-initiatives-to-reduce-climate-impact">our report</a> to reap any possible gain in efficiency.</p></li>
<li><p>Far more research is needed to develop alternative aviation fuels that genuinely cut emissions. Given what we’ve seen so far, these are unlikely to be biofuels. E-fuels – liquid fuels derived from carbon dioxide and hydrogen – may provide such a solution, but there are challenges ahead, including high costs.</p></li>
<li><p>Governments can – and some European countries do – impose carbon taxes and then invest into lower carbon alternatives. They can also provide incentives to develop new fuels and alternative infrastructure, such as rail or electric planes for shorter trips. </p></li>
</ol>
<h2>How you can make a difference</h2>
<p>Our research paper was released late last year, at a World Travel and Tourism Council event linked to the <a href="https://theconversation.com/au/topics/cop25-79570">Madrid climate summit</a>. Activist Greta Thunberg famously sailed around the world to be there, rather than flying.</p>
<p>Higher-income travellers from around the world have had a disproportionately large impact in driving up aviation emissions. </p>
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<p>This means that all of us who are privileged enough to fly, for work or pleasure, have a role to play too, by:</p>
<ol>
<li>reducing our flying (<a href="https://theconversation.com/people-hate-flight-shame-but-not-enough-to-quit-flying-130614">completely</a>, or <a href="https://theconversation.com/flight-shame-flying-less-plays-a-small-but-positive-part-in-tackling-climate-change-125440">flying less</a>)</li>
<li><a href="http://www.offsetguide.org/avoiding-low-quality-offsets/">carbon offsetting</a></li>
<li>for essential trips, only flying with airlines doing more to cut emissions.</li>
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<p>To really make an impact, far more of us need to do all three.</p>
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Read more:
<a href="https://theconversation.com/climate-explained-how-much-does-flying-contribute-to-climate-change-127707">Climate explained: how much does flying contribute to climate change?</a>
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<img src="https://counter.theconversation.com/content/127800/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Susanne Becken is on the Sustainability Advisory Panel of Air New Zealand. Her report, Airline initiatives to reduce climate impact, was co-written with Paresh Pant. This research paper was done in partnership with travel technology company Amadeus.</span></em></p>We analysed what the world’s top 58 airlines – such as American Airlines, British Airways and Qantas – are doing about climate change. Even the best airlines are not doing anywhere near enough.Susanne Becken, Professor of Sustainable Tourism and Director, Griffith Institute for Tourism, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.