Japan has a solid conventional submarine build program producing high quality and capable evolved MOTS products. At 4000 to 4200 tonnes they are of a size that many seem to think is important for Australia’s future submarine program.

31st Oct 2012

 SEA 1000

Byline: Rex Patrick / Sydney

Japan has a solid conventional submarine build program producing high quality and capable evolved MOTS products. At 4000 to 4200 tonnes they are of a size that many seem to think is important for Australia’s future submarine program. It’s therefore not surprising that the notion of Australia leveraging off the Japanese program has been floating around for as long as the project itself.
That notion seems to be maturing with reports appearing quite recently in the press of potential links between future Japanese and Australian programs. “Navy eyeing off new Japanese Submarines”, headlined Hamish McDonald in his 9 July Sydney Morning Herald article and again in The Australian in a 27 September article by Tokyo correspondent Rick Wallace, “Japan Tech Deal Could Help Power Our Subs”. Both articles reported a visit to Japan by members of the SEA 1000 team.
Media speculation aside, the Japanese submarines have been on RADM Moffitt’s sonar for some time. The Admiral’s duty to Government prior to first pass is to explore all options, and he has fastidiously been doing just that. Followers of Senate Estimates hearings know that the recent visit to Japan by the Future Submarine Project team is not its first.
To address the rising awareness and public interest, this month’s SEA 1000 article takes a look at Japan’s submarine force solution and its applicability to Australia.
Japan’s submarine program produces one new boat every year. The production responsibility is shared between Kawasaki Heavy Industries and Mitsubishi Heavy Industries, with each company delivering a new submarine year about.
The Japanese Self Defence Force (JSDF) operates 18 submarines, although a plan to increase the fleet over time to a force of 22 has been announced. Current JSDF operational submarines classes are the Harushio, Oyashio and Soryu. It is the newer Soryu that will be the focus Australian interest and of this examination.
The Soryu is evolved from the Oyashio class submarine. It is 84 metres long, 9.1 metres in diameter and displaces 4,200 tonnes when dived. The hull is officially designed to take the boat to a depth of 300 metres.
Its propulsion chain is based on two Kawasaki diesel generators, designed in conjunction with MAN, charging batteries that power a 5.9 MW Fuji Electrics main motor driving a seven bladed propeller. The boat is also fitted with a Stirling AIP system, integrated under a licence agreement with Kockums of Sweden, which can be used to eliminate the need to snort in high threat environments.
When operating on batteries the Soryu is a very quiet boat. It is coated in anechoic materials to assist in reducing its target strength in active sonar scenarios.

The combat system is largely indigenous. It has a number of sonar arrays, including bow, intercept, flank and towed - and the submarines are also fitted with optronics masts. The Soryu has six 533 mm torpedo tubes that can fire the Mitsubishi Type 89 Torpedo, the UGM-84 Harpoon anti-ship missile and mines. Consistent with all large hulled submarines, the boat can carry (in submarine terms) a large number of weapons: 30.
The boat is operated by a ship’s complement of 65.
Prima facie, the Soryu, with its unit cost of about $600 million, would and should be of interest to the ADF as a low risk and capable submarine option.
There are, like all MOTS solutions, some areas where the boat would fall short of the purest 2009 Australian Defence White Paper (DWP) submarine requirement. This was recognised by RADM Moffitt at the October 2011 Estimates when he stated with respect to those requirements, “in terms of size overall - but not capabilities overall - the Japanese Soryu class could come close”.
Limitations of this submarine include it maximum diving depth and a relatively high indiscretion ratio on account of high electrical consumption. Other areas where the boat falls short are range and endurance.
Despite its size, the Soryu Class has a quoted range less than that of a Collins or something like a Type 214.
This should not appear surprising to readers of this series. Back in May 2011’s APDR, the many factors that affect range and endurance of a submarine were discussed. These factors included fuel load, hull and equipment efficiencies, reliability/maintainability and redundancies, stowage capacity and payload capacities. The conclusion was reached that hull size does not contribute greatly to a submarine’s range and endurance capabilities. Whilst larger submarines can carry greater fuel loads, they require more fuel to push themselves through the water and have bigger diesels, bigger batteries, bigger main motors, more auxiliary equipment and larger crews. Hull size does improve crew habitability and also contributes to payload capacity, which may keep a boat at sea longer. The bottom line is that if there are increases in range and endurance caused by size, it is certainly non-linear. Empirical data was provided to support the claim.
The 6,100 NM quoted range of Soryu, most likely so due to limited storage capacity of diesel oil, is in no way a restriction for the Japanese. A look, firstly, at the Japanese Constitution and then at their 2012 “Defense of Japan” paper (DOJ 2012) published by the Ministry of Defense explains why.
The Japanese people desire lasting peace. Principles of pacifism are enshrined in Article 9 of their Constitution, which renounces war, the possession of war potential and the right of belligerency by the states. Whilst these provisions do not deny Japan an inherent right of self-defence, this constituted moral position places limitations on long-range submarine deployments.
At a lower and more tangible level, the DOJ 2012 clearly articulates the strategic environment in which the JSDF must operate. It focuses on 1) the countries of North Korea, with its nuclear missile program foremost in Japanese minds, 2) China, with its increasing military capabilities and expanding and intensifying activities in waters close to Japan, 3) Russia, with a reinvigoration of military activity and, it also makes significant reference to 4) the long standing issues of territorial disputes within its region.
In the context of these strict regional ambitions, it states the following in regard to its submarine force: “As the geographical relationship between strategic sea areas and military bases are taken into account in the 2010 NDPG, the submarine units have increased the number of vessels to 22 to reinforce the posture to deploy submarines in key sea traffic points in the East China Sea and the Sea of Japan, to regularly conduct ISR over a wide range of waters surrounding Japan including the south western area, and to ensure the superiority of information and swiftly detect indications of security.”
A couple of other program related drawbacks associated with a Japanese MOTS solution include individual-submarine/class longevity concerns and some techno-culture concerns.
With respect to individual submarine longevity and on account of the fact that between the two shipyards, one new submarine is produced every year, the Japanese boats may not be explicitly designed for the 30 to 40 year life span requirements of the RAN. This does not mean that they wouldn’t or couldn’t remain in service for more than 20 years, rather that it is an issue that would at least need to be considered by the SEA 1000 team.
With respect to class longevity, it is appreciated the Soryu Class will only remain in service with the JSDF for 20 years after the last submarine of the class has been delivered. It is understood, for example, a new class of submarine to replace the Soryu is being designed now and that the first will be ready in 2016. A buy of the Soryu by Australia in the next few years would see them operated in parallel with the JSDF for about 15 to 20 years after which the RAN will be left operating a platform that is used by no other Navy. Everyone is all too well aware of the costs associated with operating an orphaned submarine class later on in its life cycle. This concern can be partially offset by the fact that the replacement for Soryu is likely to be an evolution of it, with a certain degree of component commonality.
Finally, noting there is a commitment from both sides of politics in Australia to build submarines in Adelaide, techno-culture issues (difference in the industrial, commercial and legal framework of Japanese industry and, indeed, cultural and language differences) must be laid out on the table for consideration.
Whilst the Soryu Class is, on first inspection, a viable option to meet much of Australia’s future submarine requirement, it is simply not available.
The same constitutional section that renounces war and indirectly limits the range requirements of its submarine force also restricts the export of arms from Japan.
Export prohibition is not explicit in the Constitution per se, but the regulations that stem from it seem to be. Admiral Moffitt summed up the situation at this February’s Senate Estimates when he stated “It is not the constitution so much as the regulations that the government has chosen over many years to apply to military equipment, and that looks like it might be in the process of shifting somewhat. But it is nonetheless still true to say that the Japanese submarines are not available in the marketplace, even though they do exist, and we understand they are very good submarines”.
None the less, discussions between Japanese officials and SEA 1000 officers have been taking place. These discussions, however, are not related to submarine purchasing, rather to co-operation on equipment, and specifically propulsion related equipment.
The Australian newspaper stated that Defence Minister Smith had ”confirmed that hi-tech Japanese submarine propulsion systems were the kind of technology transfer that a deal with Japan might cover and that is allowed for Japan”. Indeed, DOJ 2012 states that Japan wishes to maintain, foster and upgrade defense production and technology bases and as part of this strategy there is an initiative to have “defense equipment cooperation with its security partners” and “international joint development and production”. It reinforces a statement by the Japanese Chief Cabinet Secretary on 27 December 2011 concerning the Standards for the Overseas Transfer of Defense Equipment making it possible to “engage in joint development and production with the USA and other countries with which Japan has a cooperative security relationship, based on the premise of stringent management”. As well as making it easier to procure advanced equipment, it is anticipated that this would have the advantage of reducing the unit production cost of production by curbing development costs and increasing production volumes, and also further support the construction.
Australia’s interest in the Japanese propulsion train fits within the scope of options three and four announced by the Minister in May of this year; option three being an evolved design that enhances the capabilities of existing off-the-shelf designs, including the Collins Class; and option four being an entirely new developmental submarine.
Noting the size of Collins and the, largely unexplained, 4000+ tonne requirement of the bespoke design, the Japanese drive train would offer Department of Defence officials with an ability to claim that this most important part of the submarine comes with a certain level of in built de-risking (although this line of argument will need to be put into context – as will be done below).
Submarines aside for a moment, another Japanese submarine concept that has taken hold with some inside Defence is the continuous manner in which Japanese design and build their submarines.
RADM Moffitt described a continuous build program to the Senate Foreign Affairs, Defence and Trade Legislation Committee in May. “That leads you to a notion of batch-building. It might be that the first batch will be two and the second batch will be nine. The number of submarines in each batch will be driven by the maturity of technology and when we wish to incorporate that technology into the design, as well as how quickly we can do that during the course of the program and adapt the build yard to the new or slightly evolved design. In fact, that is pretty much describing the Japanese model. They have been continuously building submarines since the 1960s and they gradually evolve each design. They evolve it perhaps in some significant ways, but relatively few numbers of evolution. Between what they have today and what they had previously, there are really only four key things - some of which are quite major - which have been changed in the design. The next evolution of the design, as we understand it, will be to incorporate lithium batteries. That is the sort of thing we are talking about …”
Unfortunately caution is required in replicating the Japanese model. Without significant increases in Defence expenditure, it is simply unaffordable. The Japanese nominal GDP is just shy of four times that of Australia’s and its submarine program was established during its economic heyday.
1 United States 15,076 SSBN and SSN National Investment
2 China 7,298 SSBN, SSN and SSK National Investment
3 Japan 5,867 SSK National Investment
4 Germany 3,607 SSK Supported by Export
5 France 2,778 SSN and SSK Supported by Export
6 Brazil 2,479 SSN Assisted by France
7 UK 2,431 SSN National Investment
8 Italy 2,199 Nil Not Applicable
9 Russia 1,850 SSBN, SSN and SSK Supported by Export
10 India 1,827 SSBN (Emerging) National Investment
11 Canada 1,739 Nil Not Applicable
12 Australia 1,487 Nil Not Applicable
13 Spain 1,480 SSK Supported by Export
14 Mexico 1,154 Nil Not Applicable
15 South Korea 1,116 Emerging SSK National Investment

Table 1 – 2011 GDP IMF Ranking
Making a decision to design one’s own submarine takes something more that a decision to build to the design of a third party in-country. A submarine design decision requires an industry wide investment.
Germany, by way of example, has an submarine industry consisting of Atlas Elektronik for the combat system and torpedoes, Diehl BGT Defence for subsurface to air missiles, Carl Zeiss for the periscopes, Aeromaritime Systembau or Rohde & Schwarz for above water communications, L-3 Communications Elac Nautik for underwater communications Raytheon Anschutz for the navigation systems, Gabler for the mast hoists, EADS Astrium for submarine rapid surfacing equipment, Ballonfabrik See & Luftausrustung for submarine escape systems, Draeger for submarine air quality control, MTU for diesel engines, Piller Power Systems for generator control systems, Hawker or GAIA or Exide Technologies for submarine batteries, L-3 Communications AUROATLAS for static power supplies, Siemens for the permanent main motors and Fuel Cell system, Renik for submarine shaft equipment and HDW, with a in-house team of about 600 engineers, building the platforms and integrating the other suppliers’ sub-systems.
France has similar depth in its industrial base, while Spain combines its significant in-country industrial capability with the US and UK partners.
Designing and building submarines is an expensive game. Countries with smaller GDPs than Japan that do have a submarine design capability sustain it through the export of submarines to other customers. It does not appear as though Australia is seeking to do this – though it was one of the many thoughts behind building Collins here, rather than in a European shipyard.
There is real danger that we might start down that path, without a sustainable Government commitment for the required money necessary to do the job properly and see it through to completion.
Despite it being a possibility, it makes little sense to select a Japanese drive train to insert into an option three or four Australian submarine and claim that it reduces the risk significantly. A “technologically refreshed” Collins class submarines, as option three was referred to by RADM Moffitt in last month’s Estimates, is essentially a new design of submarine. Once a permanent magnet motor, new diesels, lithium ion batteries, AIP, bridge type hoistable masts, special forces facilities, AUV cradles or locks, new weapon discharge technologies, Multiple All Up Round Canisters, flexible payload technologies and the like are included, the only resemblance our future submarine would have to Collins would be only the steel hull. Even then, there has been commentary suggesting that we should change the shape and pressure hull diameter. In effect, an evolved Collins would be a new design of submarine.
A submarine is not a collection of proprietary items or systems, rather a carefully integrated design that accommodates weight, space, signature and performance contributions of every component part. Integration is absolute and central to a submarine’s operational capability, sustainability and reliability. ASC, or even “Team Australia”, doesn’t have the requisite design experience to do it. RAND and RADM Rowan Moffitt both know this.
Perhaps the visits to Japan are being conducted to ensure that an option three or four alternative to Kockums is seen to exist?





APDR at a glance