Beyond the Collins Class: what next for Australia’s submarines?

Will a Team Australia approach get the job done? AFP

Federal Defence Minister Stephen Smith has announced an inquiry into the reliability of Australia’s six Collins Class submarines.

He also called for US assistance in building new submarines to replace the Collins fleet which is scheduled to be in service until 2025. But what are the options for Australia’s so-called Future Submarine?

And why does Australia need submarines in the first place?

Simply put, submarines are an ideal weapon if you’re looking to deny command of the sea to your opponents.

In the Second World War, German submarines very nearly won the Battle of the Atlantic by the simple strategy of trying to sink allied ships quicker than they could be replaced.

Some 3,500 ships were lost before the submarines were defeated, so it was a close run thing. On the other hand, United States Navy submarines were successful in strangling Japan’s trade routes.

There are other examples of submarines having a wholly disproportionate influence on the outcome of a conflict. In the Falklands War, a small number of British submarines prevented the Argentinean Navy from re-supplying their forces by sea.

While the submarine is often seen as the apotheosis of aggressive warfare, it is also an invaluable element of defensive warfare, given its ability to take the fight right up to an aggressor, not only by direct attack, but also by covert surveillance or even by the implied threat that they just might be there.

The Australian experience

Australia has included submarines in its defence strategy, right from the creation of the Royal Australian Navy (RAN) in 1911. Indeed, it’s worth reading the story of the submarine AE2 in the Dardenelles at the time of Gallipoli.

The RAN has operated submarines continuously since 1967 when the first of six British-built Oberon Class submarines entered service.

They were, in turn, replaced by the six Australian-built Collins Class submarines, about which much has been said and written – both good and bad.

In December 2007, the Government announced its intention to replace the Collins Class with 12 new submarines which would be built in Adelaide.

So what is available?

Well, submarines can be divided into two main groups based on their propulsion type: nuclear and conventionally-powered.

Conventional propulsion

Most conventionally-powered submarines are built around a diesel-electric propulsion system, where the submarine is propelled by an electric motor powered by variants of the traditional lead-acid battery.

These are big batteries: a conventional submarine can have up to four battery sections with a hundred cells in each and each cell weighing nearly a tonne.

These batteries are charged by diesel generators which, being “air breathing”, require the submarine to be surfaced or at periscope depth in order to operate.

This is the Achilles’ heel of the conventional submarine, as they are at their most vulnerable while at or near the surface (even when charging is taking place using a snorkel or snort mast). This period is described as “indiscretion”.

Recent developments in conventional submarine propulsion technology have therefore focused on reducing the indiscretion rate by use of air-independent propulsion (AIP) such as fuel cells or closed cycle heat engines.

Nuclear propulsion

A nuclear-propelled submarine uses a nuclear reactor to generate steam, as occurs in a nuclear power station.

Unlike in a nuclear power station, however, the steam in a nuclear submarine is used to drive propulsion turbines as well as providing electrical power.

Modern nuclear cores will last the lifetime of the submarine – about 25 years – and as a result, the submarine can operate at high speed for unlimited periods without refuelling.

Nuclear submarines also provide enough electrical power to support a highly complex combat system, with extensive sensors and weapons systems, all controlled by highly sophisticated tactical data management systems.

From an operational perspective, this would seem to be an attractive option. But nuclear submarines and their support do not come cheap, and to be successful it would require the support of a currently non-existent Australian nuclear power industry.

The Defence Minister has clearly stated the replacement for Collins will not be nuclear-powered and given the current political climate in relation to all things nuclear, this position is unlikely to change, despite the urgings of reporters such as Greg Sheridan in the Weekend Australian and others.

Royal Australian Navy/Flickr

The Australian submarine

Unlike the earlier Oberon Class, the Collins Class submarines were designed to cater for uniquely Australian conditions, most notably the tropical waters in which they would operate and the large distances they would need to travel.

These submarines were also designed to have a highly-capable and therefore power-hungry combat system, broadly equivalent to the capability of a nuclear submarine.

This resulted in a very large submarine, which, when built, was the largest conventionally-powered submarine since the Second World War.

This unique solution to a unique set of requirements has resulted in the submarine being an orphan – only the RAN operates the Collins Class, which can be an uncomfortable experience when dealing with such a complex technology, since it denies the RAN the option of sharing experiences with other navies operating the same submarine.

This undoubtedly will be a consideration when looking at the replacement options.

What can we do?

Apart from Japan, few nations operating high-capability ocean-going submarines use such large conventional submarines. Most (e.g. USA, UK, France) have gone down the nuclear path.

Conventional submarines operated by friendly nations tend to be smaller and therefore more constrained in their operational range.

This stems from their traditional use closer to home than the RAN requires.

So what options do we have? Well, we could:

  • Develop a new, large conventional submarine, probably unique to Australia, in conjunction with a foreign capability partner.
  • Acquire lower capability submarines from the range currently available from submarine-building nations such as France, Sweden, Spain, Germany, with as much modification for Australian conditions as the design will allow.
  • Develop a modernised version of the Collins in conjunction with the original submarine designer) and other capability partners.

Home advantage

The Australian Government has stated that any such future submarine will be built in Adelaide, but that this does not necessarily mean that it will be built by ASC (formerly the Australian Submarine Corporation).

This is due to the government’s desire to ensure there is appropriate competition to keep costs down.

While this is a laudable aim, it may not be a practicable when considering such a major project.

It is worth noting there are (sensibly) only two military shipbuilders/assemblers in the UK – BAE Systems and Babcock International (and they are collaborating on the aircraft carrier project) while there are potentially five in Australia: ASC, BAE Systems, Thales, Forgacs and Austal.

Even in the US, the two submarine builders (General Dynamics Electric Boat and Northrop Grumman Newport News) are co-operating in a successful bid to keeps costs down and deliveries on schedule.

For Australia to succeed in building a new class of submarines it will need to pool the best expertise available and get started soon if in-service dates to replace Collins Class submarines are to be met.

If ever a project required a Team Australia approach, this is it.