Australia Is Getting The Baddest Diesel Electric Submarines On The Planet

It was one of the biggest international defense contracts in recent memory. Australia’s Collins class submarine replacement program, also known as SEA1000, looked to procure 12 highly advanced diesel-electric multi-role submarines, each equipped with the latest in air independent propulsion (AIP) and quiet running technologies.

These new foreign-designed submarines, which would be outfitted with American combat systems, would be fielded in the next decade and would serve into the latter half of the century. The program’s total cost is estimated just shy of $40 billion. Shipbuilders from Germany, Japan and France were in the running to land the contract. So who was Canberra’s final choice?Let’s meet the competition:

Germany’s Thyssen Krupp, known the world over as master builders of submarines, put forward an enlarged variant of their extremely popular and capable 1,900 ton displacement Type 214 AIP capable attack submarine, known as the Type 216. Its bid was predicted to be the lowest of the lot, landing somewhere around half the cost.

Thyssen Krupp

Japan’s Mitsubishi-Kawasaki offered up a derivative of its own 4,200 ton displacement Soryu class diesel-electric submarine. Australia and Japan have growing ties, especially when it comes to national security interests, and the fact that the type was already in production—and the right size—seemed to give the Soryu an edge. Existing synergy between Japan and Australia in submarine operations and development was also seen as a major competitive advantage, especially since the two countries are hemispherical neighbors with aligned strategic interests.


Finally, there’s French naval ship builder, DCNS, which is majority-owned by the French government. DCNS went in a different direction with its design. Instead of upsizing a smaller boat or selecting one off the shelf, it downsized its nuclear powered next-gen Barracuda class submarine to meet—and likely exceed—Australian requirements. They called it the Shortfin Barracuda Block 1A.

Australian Government

The franco option was viewed as least likely to win, and the immaturity of the design seemed to carry risk. But it’s an adaptation of the very best submarine technology the French have to offer, it is likely the most capable. It would retain the ultra-quiet pump-jet propulsion system found on the nuclear Barracuda variant and many other advanced nuclear submarines in the world, including America’s Virginia and Seawolf class fast attack boats.

And The Winner Is…

DCNS. On April 26, Canberra shocked the sub procurement community. Unofficial explanations as to why Australia chose the French included questions about the uncertainty of Japan running a major arms export program. Previous Japanese AIP boats used Swedish Stirling Engine-based technology, although lithium-ion batteries were to take its place in the design intended for Australia. Also, Japan’s subs are built to a 20-year lifespan, while Australia intends to keep their next generation subs in the water for 30. The size of the living spaces may have also been a major concern.

When it came to Germany’s massively supersized (as in doubled in displacement) design based on the existing Type 214, it is widely rumored that the concept present far too much technical risk for Australia’s liking. Beyond these speculative reasons for going with the underdog DCNS design, there are other elements that were likely factored in heavily to Australia’s decision. These included dramatic industrial offsets, the ability to construct the boats locally, technology transfer and the contractor’s ability to work with US combat systems suppliers. Size and overall capability, not price, were likely the nails in the coffin for the Shortfin Barracuda’s competitors. In the end Australia will end up with a French nuclear submarine design adapted for diesel-electric propulsion. One that will be built in Australia and its combat systems furnished by US defense contractors. It truly is a defense program that spans the globe.  

The advent of modern Air Independent Propulsion for diesel-electric submarines, and the improvement in battery power over the last two decades, have delivered nuclear submarine-like capabilities in far less complex, smaller and cheaper submarine designs. The most modern AIP boats can stay submerged for weeks at a time and are in some cases even quieter—and thus more deadly—than their nuclear counterparts. This is no secret, as diminutive AIP capable foreign submarines are known to have wreaked havoc on American flotillas during complex wargames. The US Navy even leased Swedish Gotland class AIP capable submarines to see train against, a move that turned out to be a humbling experience for America’s seagoing force.


France has been pushing to expand the idea of what a diesel-electric submarine with the latest AIP technology looks like. The Shortfin Barracuda appears to be a realization of this exact concept, which was previously dubbed the SMX-Ocean. This super-sized diesel-electric AIP design bridges the gap between the gold-plated nuclear fast attack submarines and the traditionally smaller and more regionally-focused diesel-electric submarines.  

Australia’s willingness to pay such a high price for a dozen non-nuclear boats—about $3 billion per hull—surprises some. But this is actually the cost of the program as a whole, divided over the number of hulls procured. So it includes research and development, integration of combat systems, setting up indigenous production and support infrastructure.

The truth is that diesel-electric submarines with advanced AIP capability can be had for around $500-$700 million a boat if bought directly from a manufacturer such as Germany’s Thyssen Krupp. Even Israel’s highly modified Dolphin II class of submarines cost around $500 million each. But the Shortfin Barracuda is a much larger boat than the Dolphin II and is packed with additional combat capacity and features. Most importantly, it will end up being a relatively new design built in an entirely different country than its origin. It will also feature American combat systems.


Good Decision, or Bad?

It depends. It’s hard to understand why Australia would pass up Germany’s Type 216, a variant of a highly proven design from a top manufacturer for half the cost. Two for one is an undeniably awesome proposition, especially for a submarine force that has a lot of ocean to patrol. Yet manning and maintaining that size fleet is really outside of Australia’s stated interest. Additionally, the Royal Australian Navy is accustomed to operating larger submarines, with the Collins class having a nearly 3,500-ton displacement. Stepping down even to a drastically enlarged derivative of an existing type may be unacceptable, regardless of the cost.

Japan’s offering seems like a good mix of size, price and geopolitical convenience, but since Australia has a requirement for just twelve boats, maybe going for an “in-between” solution wasn’t attractive enough. 

In the end, going for the full package just short of procuring a nuclear submarine, which was not an option, may have been seen as the best option considering just how important these submarines will be strategically. In fact, buying what is really a nuclear submarine redesigned for conventional propulsion, may cost more but it also may provide the best “future-proofing” and long-term combat effectiveness for the decades to come. DCSN also has experience with fuel-cell based AIP capabilities, which along with lithium-ion batteries, are seen as cutting-edge when it comes to AIP concepts and fielding the quietest boats possible.

Australian Government

A Golden Opportunity For The US Navy?

The US all-nuclear submarine fleet is already over-tasked, and the situation is only going to get worse. Geopolitical realities around the globe, including the reawakening of the Russian Bear, China’s rapid military expansion, and North Korea’s nuclear and submarine ambitions will all put increased pressure on America’s fast attack and guided missile submarine fleet. These boats are also tasked with spying, special forces delivery operations, and land attack and carrier escort duties. Additionally, the rapid proliferation of very quiet diesel-electric submarines, some with AIP capability, around the globe degrades America’s qualitative advantage in the undersea arena.

The Virginia class fast-attack boats currently in production cost about $2.7 billion apiece. In all, the US has roughly 55 SSNs and four refitted Ohio class SSGNs in inventory, which sounds like a large number, but a significant portion of the fleet is undergoing training, maintenance or in port at any given time. One solution to this fast-attack submarine deficit would involve procuring diesel-electric submarines once again.

Virginia class fast attack submarine in drydock., Huntington Ingalls

The last conventionally-powered sub in service with the US Navy was the USS Blueback, which during the twilight of its career served as an aggressor submarine for nuclear submarines to practice against. The sub was finally retired in 1990 and now sits as a museum ship at the Oregon Museum of Science and Industry.

The Blueback did not feature AIP technology and clearly diesel-electric subs have made a quantum leap in capability in the last two and a half decades since its retirement. With all this in mind, the Shortfin Barracuda that Australia is willing to pay huge sums of money to develop and equip with American combat systems would be an ideal alternative to the overworked, all-nuclear US force.

By purchasing an off-the-shelf submarine—with the most advanced technology available for its class, and with US combat systems already integrated into it—the Pentagon could save billions in acquiring a nearly perfect supplement to its current undersea fleet. Even if the US could buy three of these super-sized AIP capable boats for the price of a single Virginia class nuclear submarine, it could result in just the right high-low capability mix to properly confront the threats of the future. Not only that, but Australia and France would be partnered in the program, assuming risk for future upgrades and capability enhancements.

Replacing one Virginia class buy out of every four ordered with a common US-Australia diesel-electric submarine would mean that for every four boats the Navy would have acquired they now have six. And no matter how capable a submarine may be it can only be in one place at one time. In other words, numbers matter, and the current nuclear only force is not addressing this dire reality.

Another factor that must be considered with such a strategy is basing. Right now America’s nuclear submarines are only based in US territory. But a diesel-electric submarine can be forward deployed and maintained far easier, without the intense security risk associated with parking a nuclear reactor in someone else’s backyard. This means that the US could forward deploy these submarines to hotspots around the globe. By focusing an advanced diesel-electric submarine force on regional operations and forward basing, some of the advantages of a the much more expensive nuclear fast attack submarine begin to fade.

The Pacific is especially relevant for this kind of concept. Not only is it the strategic focus of the Pentagon going forward but it is a vast  theatre of operations where the “tyranny of distance” neuters even some of the world’s top weapon system.


Take the US Navy’s current rotational basing of Littoral Combat Ships in Singapore for instance. A similar strategy could be executed with advanced US diesel-electric submarines. In fact, a Littoral Combat Ship paired with such a submarine would be a very interesting and effective combination. Additionally, the Littoral Combat Ship could act as a tender for the submarine to a certain extent, enhancing its range and flexibility. These boats could also be deployed to locales like the Philippines and Japan, and since Australia will have all the facilities necessary to support them and to perform deep repairs and servicing, America’s infrastructure investment would be minimal when it comes to permanently deploying them to the region.

The Pacific is not the only area where these subs could be based. The Baltic Sea, which is increasingly a hot spot, as well as the Middle East would both be relevant basing areas. Rota Spain is another location that makes a lot of sense and these subs could work in tandem with America’s cadre of destroyers that are now based there. These smaller boats are extremely well adapted for operations in shallow and complex littoral environments, and could prove more tactically relevant than their larger nuclear counterparts in some instances.

The Same Old Hurdles Remain…

Obviously the two biggest hurdles for the Navy actually executing such a logical solution to the tactical and strategic undersea issues that lay before it today are the shipbuilding lobby and the service’s almost religious devotion to an all nuclear submarine force.

By truly buying a boat off the shelf, great savings can be realized and capability and design creep, which are the plague of most big defense programs, can be averted. The problem is that this is not a good thing for US shipbuilders who are already scrambling over a relatively static ship-building pie, one that has shrunk over the decades. There is also some strategic points gained by keeping multiple shipbuilders in business, but in a globalized market, even when it comes to ships and weapons, this is somewhat of an antiquated although still highly leveraged argument.


It is possible that the exact same designs could be built right here in the US under license. Although doing so could add significantly to the cost of each boat.

Strangely enough, the Navy’s obsession with demanding nuclear propulsion for all of its submarine force could be an even larger obstacle to contend with than shipyard politics. The “nuke” ideology is deeply engrained into America’s submariner culture that many look down on diesel-electric boats as junk in comparison to their gold plated super-subs. This mentality may be self-serving, but it won’t fix the increasing fast-attack submarine deficit. Quite frankly, neither will a new President. Even if defense spending skyrockets, submarine production won’t necessarily increase dramatically. These boats are simply too expensive to build and maintain to see fleet size expansion without looking at other technologies and implementing a solid, high-low capability mix strategy.

Now, with Australia footing the bill to develop a perfect candidate for the lower end of such a strategy the Navy has never been positioned better to dramatically increase their presence under the high seas. It will just take a cultural leap of faith and the political will to make it happen.

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