January 30, 2014

Australian interest in Japan Soryu Submarine's Propulsion System

 A Soryu Class submarine - in this shot visiting the US Guam naval base.
A diagram of some Soryu Class features.

Mentioning the Soryu see the latest of June 11, 2014’s Australia's Future Submarine - Swedish vs German Claims http://gentleseas.blogspot.com.au/2014/06/australias-future-submarine-swedish-vs.html . It is unclear whether Germany or Sweden hold the strongest intellectual property rights to the Soryu's Stirling AIP. While Germany seems to have the strongest licensing rights over the Soryu's diesel. 

For the latest specifically on the Soryu see:
If Australia were to consider buying some features of Japanese submarines - such as the Soryu's propulsion system - Australia would need to be confident Japan could make this politically and economically possible. To date Japan has never exported a major weapons system. However it was reported on January 29, 2014 that Japan will complete its sale to India of Japan's indigenously developed US-2 amphibious aircraft in 2014. This US $1.65 billion export of the ShinMaywa built amphibious aircraft will be Japan's first since Japan's self-imposed ban on arms exports began in 1967. If this deal is completed smoothly Australia might have greater confidence in possible future negotiations with the Japanese Government and Japanese arms companies.

On December 7, 2013 The Australian reported:

"AUSTRALIA has asked Japan to consider providing highly advanced propulsion technology to be used in the navy's planned 12 new submarines.
[Australian] Defence Minister David Johnston has told The Weekend Australian Japanese officials had visited submarine maintenance facilities in Adelaide and talks were continuing.
In a speech to the Australian Strategic Policy Institute, Senator Johnston spoke about the Abbott government's wish to cement closer defence ties with Japan, including much closer defence-industry ties.
Senator Johnston said later he was particularly interested in the use of Japan's extremely effective submarine technology in Australia's future submarine, which is most likely to be an evolution of Australia's existing Collins-class vessels.
Japan's Soryu-class is the world's biggest and possibly the best diesel-electric submarine and Senator Johnston is particularly keen on its "drive train" - the whole propulsion system, from the propeller through to the electric motor and the diesel engine that charges the boat's batteries." See the rest of the article at

SORYU DETAILS (Pete's Comment)

The Sōryū-class are diesel-electric (SSK) submarines, with AIP, that entered service with the Japanese Navy "Maritime Self-Defense Force" in 2009. Five have been built (since 2005) with all five operational in Japan's Navy. Four more await completion. The design is an evolution of Japan's Oyashio class submarine. Eleven Oyashios have been built since 1994 and all eleven are still operational.

The Sōryūs have a very large displacement for a diesel-electric sub (2,900 tonnes surfaced and 4,200 tonnes submerged). This compares to the Collins (3,050 tonnes surfaced and 3,350 tonnes submerged) http://en.wikipedia.org/wiki/Collins-class_submarine.

Significantly the Soryu carries a higher weapons payload than the Collins which is an important endurance-operational advantage. The Soryu carries 30 "reloads" (torpedos/Harpoon missiles) compared to 22 for the Collins.

The Soryus are fitted with air-independent propulsion (AIP) based on Kockums Stirling engines license-built by Kawasaki Heavy Industries . The diesel-electric range surfaced may be around 11,000 km with AIP range 1,000+ km. Range (how much on diesel, batteries and AIP?) is one of the most complex issues involving submarines. The Soryu is mainly heavier than the Oyashio's tonnage (2,750 tonnes surfaced and 4,000 tonnes submerged) due to the addition of the AIP.

See also Kawasaki is involved in producing "more than 80" Japanese submarines http://www.khi.co.jp/english/ship/product/submarine/index.html .

Possibilities of technology Soryu transfer from Japan to Australia particularly concerning the propulsion system were described at Japanese Media Now Openly Talking about Japan-Australia Soryu Deal, February 17, 2013 http://asw.newpacificinstitute.org/?p=11560 .

According to http://www.globalsecurity.org/military/world/japan/2900ton.htm: The Soryu features higher automation (particularly in combat systems) and computer-aided X control planes. The X rudder configuration was first developed by Kockums for the Gotland. The X rudder provides the submarine with greater manoeuvrability and also enables operation close to the seabed. As with most modern submarines the Soryu's hull is clad in anechoic coating (to reduce sonar and other forms of detection) and the interior features sound isolation of loud components. The hull is HY-80 alloy (the same as the USN's Los Angeles class SSN) steel. 

Japanese subs have a short service life averaging around 20 years compared to 30 years for most SSKs. It is not known whether the Soryu's propulsion system is designed for a less than 30 year service life.

Japan's lack of experience in exporting submarines or other major weapons systems has many political, legal and technical support implications that Australia would need to resolve and feel confident about.  Japan's US-2 amphibious aircraft sale to India provides a limited test of Japan's ability to export arms. A Collins II deal might test Japanese companies ability to integrate their product in simultaneous negotiations with Australian, European and US submarine arms companies.

But then again the political, strategic, and repair-maintenance advantages of choosing a propulsion design from an Asia-Pacific ally like Japan must be factored in. Such advantages would not be present if Australia purchased propulsion systems from more distant Germany (HDW), Spain (Navantia), Sweden (Kockums) or France (DCNS). Japan and Australia also have a joint interest in containing China.

One confidence booster is that the main builders and presumably sellers of the Soryu, which are Mitsubishi and Kawasaki, are highly export and customer support orientated. Such confidence would assume that the corporate culture in Mitsubishi's and Kawasaki's defence product divisions are similar or the same as their civilian product divisions.

As the Soryu combines many of the best European technological features and in a design near to SEA 1000's Asia-Pacific endurance requirements the Soryu Class propulsion system looks a promising option for Australia.



Anonymous said...

Actually the x-rudder was first introduced in the Sjoormen class submarines thirty years before Gotland was launched. This rudder configuration has since been used for all Swedish subs including Gotland.

Pete said...

Hi Anonymous

Thankyou for the clarifying comment. Sweden certainly has a record of technical innovation in its weapon systems, including subs like the Sjöormen class. Notably all five of the Sjöormen's were sold to Singapore as the Challenger Class - see http://en.wikipedia.org/wiki/Sj%C3%B6ormen-class_submarine .



jbmoore said...

The Japanese I think, hold the record for largest diesel-electric submarines with the I-400 class (http://en.wikipedia.org/wiki/I-400-class_submarine ). So, it is not surprising what they have accomplished. They always built excellent torpedoes and subs. The problem was that they never used them like the Germans and Americans did. I am sure that they've corrected that mistake since the end of WWII.

As far as exporting them, if Kawasaki Heavy Industries corporate network has been compromised by Chinese Intelligence, then the AIP and other plans have already been exported. An export ban against the Japanese would be entirely politically driven and possibly harmful economically. They need the exports now to get their economy back on track. While it would be better to export cars and computers, China has a lock on computers, rare earths, and other cheap electronic components, so arms would be an up and coming addition to the goods produced and sold by Japan.


Pete said...

Hi John

The Japanese certainly didn't know how to use their WWII subs. Their large subs, build at great expense, housed a few obsolete aircraft or acted as mother ships for what were mini suicide subs.

Penetration of the Japanese military-industrial complex by Chinese intelligence is a real problem. This may limit the level of stealth technology the US incorporates in the F-35s to be exported to Japan.



Byzcol said...

Actually the x trail is of American origin but was first deployed in production by Kockums.http://www.navy.mil/navydata/cno/n87/usw/issue_31/albacore.html

Pete said...

Hi Byzcol

Thanks for that information. I wonder whether Swedish readers of my blog will agree?



田中敦 said...

Happy to know Australian situation about this issue.

I'm Japanese and let me tell about Japanese concerns for this issue.

First,this is, as you say, the first trial for Japan to export ”weapon-like” weapon,so considerably amounts of oppositions are expected.
Indeed,US-2 flying boat may be exported to India, but it doesn't carry any weapons. Exportation of Soryu class sub includes different difficulty.

Second, Japan has deep interest in the prevention of fatal technologies' leak to other countries.
Recently, there was a plan that MHI develops new engine with Turkish local company for Altay MBT. It finally collapsed as Turkey wanted to sell new engines to other countries and Japan didn't afraid of engine technology's leak.
So Japan will require Australia's assurance that no leaks will be happened in order to sell submarine technology.

There may be many obstacles about this issue.But its success, I believe, will lead both countries to best situation in terms of economy, diplomatic relations and military.
Sorry for my poor English:)

Pete said...

Thankyou 田中敦

Your comments are well understood.

Given Japan's tradition of a Peace Constitution and a strong public and political peace movement - any Australian use of Japanese submarine engines may take years to negotiate. Many stages of ratification in Japan's Parliament, the Diet, would be expected.

Also if the Abe Government is voted out it may be replaced by a center left Government that opposes weapons exports to Australia.

I believe you are referring to the Arms Trade Treaty (ATT) http://en.wikipedia.org/wiki/Arms_Trade_Treaty that Japan and Australia have signed.

It would be difficult for Australia to demonstrate to Japan how we would use our Japanese engine powered submarines that certainly carry weapons. So the ATT may present a treaty obstacle. Though it is highly unlikely that Australia would onsell the Japanese engine technology to other countries.



1arritechno said...

Interesting comments as to how Japanese Submarine technology can come to Australia.
I believe it would be another mistake (like the Collins) to simply cherry pick just "component systems" for a future Submarine to be built in South Australia again... The Collins project was mismanaged in the extreme; Australia ended up with the most unreliable Submarine in the World & being out of Service more than any RAN vessel.!
Remember how ASC ran with a modified Kockrums design & built 6 Lemons. Instead of developing a prototype,,, they on built the design mistakes; most unprofessional.!
Our vital Defence should never be an "experiment" or a "Job for the boys" make no mistake, Australia needs a proven Submarine designed & built to a high standard.
The Japanese Soryu should be purchased as built in Japan..!

Peter Coates said...

Hi 1arritechno

The Super Soryu (an enlarged submarine for Australia only) is very much an orphan design, like the Collins.

It will have a new (as yet untested) propulsion solution = Lithium-ion Batteries which are a departure from Lead-acid Batteries that have been used on all submarines (even nuclear subs (as backup)) for over a century.

Japan will be making the Super Soryu for a customer that is not the Japanese Navy for the first time since 1938. Japan has already demonstrated it is way out of its comfort zone in the sale so far.

Unlike France and Germany there is a major Japan-English language difference. Unlimited opportunities for misunderstandings await.

Also the big sleeper, the Combat System, which is one third of the effort and cost of the sub, is being provided by LockMart and/or Raytheon OUTSIDE the CEP.

If built in Japan the US and Japan will have a bigger say in proceedings than Australia.

What could go wrong?



1arritechno said...

Yes Peter, I am aware of the planned upgrades for the most part. The only area of concern is the super Soryu version for Australia. If it were merely adding extra
modular "perfect circles" then I believe the end result would be; just as reliable.
I wouldn't say it's an orphan design, given the extensive range of R & D thus far.
Remember, the Lithium-ion Batteries are being asked for:: from all Tendering for the project- so Soryu doesn't lose credit on that! In fact Soryu is already in the process of going to Lithium,, so they will serve as development prior to Au project.
Combat & Systems management will be a concern with any build,, this could go wrong with any group. Although, I have more end confidence, with Japanese quality control.
Being their first major Military export; Japanese pride would uphold the standards.
My key concern: too much Australian involvement, could result in a Collins outcome.
The overall Politics I believe is a great concern and I agree with your key points.
We should remember that Japan is under financial pressure to open new markets and seek a means to reclaim & justify defence spending. The USA is already in favour of Australia purchasing the Soryu as it builds further defence ties with Japan and strengthens the stance in the China region ; precisely in America's interest!
Despite the positives; the Contract could stall over Soryu "secrecy" requirements.
What else could go wrong? Difficult Agreement as to percentage of Australian Build involvement and Programme Maintenance of the Soyru Class into the future... Yes, lots could go wrong with so much at stake,, you got me worried...
Well Pete, you obviously know more on the subject ; do you think Soryu is right for Australia.???



Peter Coates said...

Hi Marshall

Very difficult to say if the Super Soryu, DCNS Shortfin or TKMS Type 216 are "right for Australia"

So much "devil is in the detail"

Many variables such as:

- weight and space for future upgrades (such as the first VMPL or two additional VMPLs) need to be considered

- working with crew shortages (if crew sizes of 50+ are assumed). Crewing cannot be magically resolved with the current wishful thinking

- Australia's unique long fast transit needs means accelerated engine wear - leading to many unexpected engine overhauls-downtime - involving much cutting and rewelding of hulls. Not all contenders are prepared for that.

- One contender has a large regional navy with alliance expectations. The prospect of Australia being drawn in as a junior naval ally (on top of Australia being the US's constant Middle East ally) needs to be anticipated. Must Australia be drawn into stoushes against China?

Just some considerations.



1arritechno said...

Hello Peter,

Yes , there are some tough decisions to be made, as to what is best & fits Australia's need, as you rightly say.
You know, crewing the earlier 6 Oberon Class (65 crew) was less of a problem. They were reliable & much safer. In fact, all the Oberon's traveled further, took part in more missions, exercises & visited more ports than any Collins Class Sub to date.
I believe ; finding extra Crews wont be such a problem, with a "safer" Submarine.
Some of my friends served on Oberon's and there was great kudos in those days...
You make an important point regarding long fast transit & accelerated engine wear!
As an Engineer, I see the sense in your statement as maintenance on that level means cutting the "special steel" & hull Circles can become less than perfect following.
This area of technical knowledge, may exceed those within the selection process...
From a Logistics point, an active service Base would need to go to a location like Cairns or Townsville to position the Submarines, closer to where they are needed.
The Collins Subs were kept to the apron strings of Adelaide; because of the never ending repairs & modifications;; we must never be compromised like this again.
With the expansion of the Chinese Navy with international connections, anything is possible. Expectations by allies makes it imperative to have the right hardware in northern ports. The Only external threat down in the Southern Bite is from sharks.

thanks again,

Peter Coates said...

Hi Marshall

Without being able to talk to Collins crew, I think the highly influential postwar Royal Navy traditions that led to the positive RAN Oberon experience are long gone. Looking at http://gentleseas.blogspot.com.au/2015/10/royal-navy-finding-it-difficult-to.html modern cultural must-haves like social media connectivity are being expected by more recruits (with such hopes dashed). The UK and US navies are also discovering the social media recruitment obstacle.

A "safer" better future Aussie submarine cannot remove the social media must-have.
If Super Soryu is picked Australia may just have to do without the no-hull-cut = 650 meters diving expectation.
Yes more flexible, forward basing and maintenance would have major advantages. A Chinese base at Dili or quiet facilities at Darwin shouldn't put us off.