April 12, 2016

Why the Japanese proposal is low risk (PART TWO)

Republished with permission from the Australian Strategic Policy Institute.

This article originally appeared in the Australian Strategic Policy Institute blog, The Strategist, on April 12, 2016, with the string http://www.aspistrategist.org.au/why-the-japanese-proposal-is-low-risk-part-2/

"Why the Japanese proposal is low risk (part 2)

12 Apr 2016 | Sumio KusakaAmbassador of Japan to Australia.


[ASPI Strategist]  Editor’s note: The Strategist has invited all three SEA 1000 contenders to explain their approach to meeting Australia’s future submarine requirement.
The first post in this two-part series explored several key questions pertaining to Japan’s ability to meet Australia’s future submarine needs. Those questions concerned cruising range, internal narrowness and operational lifespan. This second post will further explain the truth about the capability of the Soryu-class and the reasons why the Japanese proposal is low risk.
Is Air Independent Propulsion (AIP) necessary?
A concern has been expressed that since modern submarines are required to spend long periods of time submerged and to secretly evacuate to safer waters, AIP capability is indispensable. Yet it isn’t included in the Japanese proposal.
As a result of incorporating lithium-ion batteries into our submarines that surpass the capabilities of AIP, Japan doesn’t believe that AIP is an indispensable capability for modern submarines.
Japan has experience operating seven submarines installed with AIP systems. But after considering the evolution in lithium-ion battery technology—higher energy density, greater safety, faster recharging times—Japan decided not to install AIP systems on submarines that will be built from 2015 onwards. [see 27SS Soryu Mark 2, LIBs only in SORYU TABLE below] 
The new Soryu-class submarine will use lithium-ion batteries instead of AIP as that technology has led to improvements in submerged endurance and speed capabilities, thereby allowing operators to continuously traverse waters using a wider range of possible speed options that simply aren’t available to AIP.
We believe that this new Japanese technology will provide a capability that exceeds that of AIP.
Are lithium-ion batteries reliable?
There’s a concern that lithium-ion battery technology isn’t yet sufficiently developed to use in submarines.
As above, Japan made a decision to install lithium-ion batteries on any submarines to be built from 2015 onwards. Prior to their installation in submarines, our battery technologies have gone through a vigorous and complete verification testing. They’ve been thoroughly evaluated in over 20 different types of tests and no issue has been found concerning their reliability. Those tests include short-circuit tests, shock-resistance tests, drop tests, overcharging/over-discharging tests, seawater soaking tests and heat tests. The results clearly demonstrate that reliability isn’t an issue. With this assurance, we finally decided to install lithium-ion batteries in our own new submarines.
What does submarine cooperation mean for the ‘special strategic partnership’?
An argument has recently emerged in Australia suggesting that deepening defence and security cooperation with Japan would narrow Australia’s strategic flexibility and pose a strategic risk to Australia. But is a point of view that regards Japan as a source of strategic risk for Australia correct? Japan and Australia share the values of democracy, human rights, the rule of law, open markets and free trade, and we have a ‘special strategic partnership’ based on our mutual strategic interests.
Australia, along with a large number of other nations, has welcomed the more pro-active contribution Japan will make to the peace, stability and prosperity of both the region and the world in line with Japan’s ‘Positive Contribution to Peace’ based on the principle of international co-operation. It’s in that context that one should regard the deepening of security and defence co-operation between Japan and Australia.
As has been the case for many years now, Japan and Australia have been deepening security and defence cooperation based on our past 2+2 discussions and agreements. The Australian government’s 2016 Defence White Paper also endorsed the strengthening of security and defence cooperation between Japan and Australia. Our participation in the CEP for the future submarine program is just one part of a much wider and more diverse story. If we were to follow the logic of the argument, which is based on opposition to Japan and Australia deepening our defence and security cooperation, we simply are left asking ‘why?’

Furthermore, Japan regards Australia as a trusted partner which is why it concluded a bilateral agreement concerning the transfer of defence equipment and technology. Under assurances given by Australia based on the agreement, necessary technology will be transferred from Japan to Australia in the event that Japan is chosen as a partner for the future submarine program. The technology transfer will ensure that Australia will be able to possess and exercise its own sovereign control over its submarines.
Sumio Kusaka is the Ambassador of Japan to Australia"

© Australian Strategic Policy Institute

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PETE'S COMMENT

Re subheading "Is Air Independent Propulsion (AIP) necessary?"

This is very much in line with what S has reported for the last 6 months. With S advice summarized in the SORYU Tables. These Tables have become more accurate and comprehensive than information released by French and German sources. 

Ambassador Kusaka advises "Japan has experience operating seven submarines installed with AIP systems" That would be SS-501 to SS-507. Then 3 more (SS-508 to SS-510) are also "LABs + AIP" Soryus, and are in the pipeline. 

Now Ambassador Kusaka has confirmed that the first Lithium-ion Batteries (LIBs) only Soryu, which is designated SS-511, was Laid Down in 2015. I call it the first Soryu Mark 2 due to its propulsion differences from the preceding Soryus.

I think AIP fails to have a "wider range of possible speed options" mainly because it must be switched on for minutes before it can sharply accelerate the submarine and AIP's chemicals are also rapidly used up at speeds over 8 knots. 

[See page 16 here The [Figure 9] plot shows how the 150kW Stirling engine AIP starts to give the SSK endurance below 8 knots thus allowing extended poise in the Baltic Sea operating area where transit times to the patrol areas would be small.]

Both Japan and, even more so, Australia have longer transit times to patrol areas. For Australia this makes the marginal value of AIP very low in our very long missions compared to classic-Baltic-AIP (or parked just outside Singapore) patterns.

SORYU TABLE (with earlier Oyashios, as at April 12, 2016)

SS
No.
Build No
Name
Pennant
No.
MoF approved amount ¥ Billions & FY
LABs, LIBs, AIP
Laid Down
Laun
-ched
Commi-ssioned
Built
By
5SS
8105
Oyashio
SS-590/ TS3608
¥52.2B
FY1993
LABs only
 Jan 1994
Oct 1996
Mar 1998
 KHI
6SS-15SS
Oyashios
10 subs
8106
-8115
various
SS-591-600
¥52.2B per sub
FY1994-FY2003
LABs only
 Feb 1994
Mar 2008
 MHI
&
KHI
16SS Soryu
Mark 1
8116
Sōryū
SS-501
¥60B FY2004
LABs + AIP
Mar 2005
Dec 2007
Mar
2009
MHI
17SS
8117
Unryū
SS-502
¥58.7B FY2005
LABs + AIP
Mar 2006
Oct 2008
Mar
2010
KHI
18SS
8118
Hakuryū
SS-503
¥56.2 FY2006
LABs + AIP
Feb 2007
Oct 2009
Mar
2011
MHI
19SS
8119
Kenryū
SS-504
¥53B FY2007
LABs + AIP
Mar 2008
Nov 2010
Mar
2012
KHI
20SS
8120
Zuiryū
SS-505
¥51B FY2008
LABs + AIP
Mar 2009
Oct 2011
Mar
2013
MHI
No
21SS
No 21SS built
22SS
8121
Kokuryū
SS-506
¥52.8B FY2010
LABs + AIP
Jan 2011
Oct 2013
Mar
2015
KHI
23SS
8122
Jinryu
SS-507
¥54.6B FY2011
LABs + AIP
Feb 2012
Oct 2014
7 Mar 2016
MHI
24SS
8123
Sekiryū
SS-508
¥54.7B FY2012
LABs + AIP
Mar 2013
2 Nov 2015
Mar? 2017
KHI
25SS
8124
SS-509
¥53.1B FY2013
LABs + AIP
22 Oct 2013
Nov? 2016
Mar? 2018
MHI
26SS
8125
SS-510
¥51.7B FY2014
LABs + AIP
2014
?
Mar 2019?
KHI
27SS
Soryu
Mark 2
8126
SS-511
¥64.3B FY2015
LIBs only
2015
2017?
Mar
2020?
MHI
28SS
8127
SS-512
¥63.6B FY2016
LIBs only
2016?
2018?
Mar 2021?
KHI
29SS
?
?
 1st of New
Japanese  Class
LIBs only
?
?
2023?
MHI?
Aus1
?
?
1st of new Aus class (if Japan chosen)
LIBs only
2028?
2030?
2033?
in Aus or Jpn?
Aus2 to 12?
?
?
between 5 and 11 additional Aus subs
LIBs only
from 2029?
from 2031?
from 2034?
??
Table courtesy of information provided to Submarine Matters. LABs = lead-acid batteries,  
AIP = air independent propulsion, LIBs = lithium-ion batteries.  

Pete

12 comments:

MHalblaub said...

Dear Pete,

On today's standard submarines a battery provides the energy for a submerged travel.

It would be a bad tactic to run the batteries empty before recharging. An enemy detecting a recharging submarine would just have to wait a few hours before the submarine has no power left. Better batteries only allow a longer submerged period.

Any kind of battery has to be recharged after a certain period. Maybe two days for a LAB and 7 seven days for a LIB. The point is after a period of 14 days both types of batteries need exactly the same time to be recharged due to the power limitations set up by the diesel generators.

A submarine with LIBs is not faster than another one with LABs. Both types can provide full power for the engine and systems.

Only an AIP can provide less time surfaced. Peak power will as always provided by the batteries no matter what type they are.

So why not use the LIB performance and an AIP? I guess the Sterling solution was not the best one.

With an partial AIP submarine the move to an AIP only submarine is not far away. LOX and Methanol together provide about the same electrical energy as diesel together with a diesel generator.

Why should not DCNS and TKMS offer a submarine with Japanese LIBs?

Regards,
MHalblaub

Wispywood2344 said...

Hi Pete.

Mr. Masao Kobayashi (retired vice-admiral of the JMSDF) had pointed out that;

1)The operational time of the JMSDF submarine is up to approximately 3 months.
2)The maximum operational time of the present AIP systems is only 3 weeks.
3)This means that the duration of the present AIP system is only half (or less) of the "patrol" period of the JMSDF submarine.
4)In other words, present AIP system is mere dead-weight in the half (or more) of the "patrol" period.

Reference
Kobayashi, Masao. "AIP推進の可能性と限界"[POSSIBILITIES AND LIMITS OF AIP SUBMARINES]. Ships of the world(vol.812):98-101

Just for your information.

Regards
Wispywood2344

Ztev Konrad said...

Wispywood , is that an 'on patrol' period of three months ( or 90 days).
Does the fuel available and consumption rate allow for that time before returning to base. Or does that indicate these vessels have a higher fuel capacity than declared ( so as to not to infringe on Japans declared self defense only restrictions)

Anonymous said...

AIP is there as a tactical measure. No need to use it during the whole patrol. Your argument classifies a lot of stuff as dead weight (e.g. safety systems that are rarely used).

Peter Coates said...

Hi MHalblaub

No-one but those Japanese naval research (and some industry) people working with the secret Kawasaki diesel and the Japanese LIBs can be certain about how different New Diesel + LIBs performance is from the current diesel, LABs and Stirling AIP.

The new diesel may have a faster operation to charge LIBs faster. Noise emitted may be better, worse or same. Also months-years of operational use is required.

Australia, using Future subs from 2030, will be able to benefit from Japan’s experience OR TKMS or DCNS if they are chosen.

If DCNS and TLKM have done a great deal of research and development they may have good LIBs – But they do not say they are relying on LIBs for all their future subs.

On AIP

Big problems with even methanol reformer fuel cell is that methano is more volatile (fire risk) than diesel. Extra fire risk fuels was one reason submarines changed from fire risky gasoline to diesel around 1900. Also methanol reformer fuel cell needs lots of heavy LOX doesn’t it?

It is not coincidental that countries with a shorter mission patterns – especially Sweden in the Baltic and Germany (for probably most missions) in the Baltic value AIP so highly. Other countries that may usually have shorter range littoral missions (S Korea, Greece, Turkey, Singapore, Israel) also seem to prize AIP.

As Wispywood2344 says the “present AIP system is mere dead-weight in the half (or more) of the "patrol" period.” for long range users.

If AIP didn’t require heavy LOX + heavy LOX containers it may be more attractive for long range, blue-water users.

Regards

Pete

Peter Coates said...

Hi Wispywood2344 [at 12/4/16 9:45PM]

"The operational time of the JMSDF submarine is up to approximately 3 months" This seems very high for actual continuous mission time at sea.

I think Ztev Konrad is right to question whether Soryu's fuel available and consumption rate allow for three month missions. Even Collins subs with a 11,500 nautical miles range at 10 knots have only operated for 55 days in a continuous mission (I read somewhere). Collins maximum is 70 days - see right sidebar of https://en.wikipedia.org/wiki/Collins-class_submarine

The 3 months may include weeks preparing a sub for a mission including some short training/engine testing runs then the main mission.

While I haven't seen fuel available and consumption rate for the Soryu (probably JMOD classified) two figures available are "6,100nm at (average) 6.5kt speed" at http://www.naval-technology.com/projects/sssoryuclasssubmarin/

So 6.5kt for 24 hour day = 156nm a day. The 6,100nm divided by 156nm = 39 days. 39 days for the contuous main mission looks more reasonable. 90 - 39 = 51 days for mission preparation, mission training and equipment (eg. diesel engine, motor and AIP) checking, I think.

Regards

Pete

Peter Coates said...

As the CEP hots up Japanese writers on the Future Sub issue are proving more productive than German or French writers:

Akira Igata, doctoral student at Keio University, Japan, has written an excellent and amusing article "Japan's submarine bid is a first date, not a marriage proposal" of 13 April 2016, which can be read at

http://www.lowyinterpreter.org/post/2016/04/13/Japans-submarine-bid-is-a-first-date-not-a-marriage-proposal.aspx

Pete

Anonymous said...

Hi Pete

Estimation of features of Soryu Mark II (27SS, 28SS) is very interesting, because these two submarines without very expensive Stirling AIP (2 billion yen) show highly spiked budget (12 billion yen) compared with 26SS. Nothing is reported on their features except LIBs, but, we cannot explain this spiked budget by only increased number and price of batteries (720 LIBs vs 480 LABs, 6 vs 3 million yen/battery).

I once said that Soryu Mark II would belong to family of 29SS rather than Soryu Mark I (26SS-16SS). I confirmed this idea by using deferent sources. I believe Soryu Mark II will equip LIBs, new snorkel generation system comprised of diesel generators and snorkel, floating deck and new sonar system, but not new torpedo GX6. New snorkel generation system is indispensable element to exert high performance of LIBs.

To lower gravity center and reduce stray magnetic field, modification of hull may be considered to arrange LIBs on the bottom floor of Soryu Mark II.

Regards
S

Ztev Konrad said...

It seems rather circular to describe AIP as 'deadweight' for more than half the mission. As you could go through the subs extensive safety systems and find much more deadweight that is never used ( hopefully). Even airliners only use their undercarriage at the start and end of journey, the rest of the time its deadweight.
The measure of the effectiveness of AIP is it an economic way of increasing underwater endurance ( other than adding more batteries) and the answer would be a resounding yes. You can clearly see the Japanese believe improving batteries by a newer technology gives the batteries an edge for now.
Any submarine design, just like a car or plane design has many competing features which have to be juggled to provide the best combinations at a reasonable cost and meet as many requirements of the user as possible.

Wispywood2344 said...

Hi Pete and Ztev Konrad.

The main mission of the JMSDF submarine fleet is blocking 3 Straits (Korea,Tsugaru,La Pérouse) to shut russian fleet in sea of Japan.
So, I have estimated fuel consumption of La Pérouse Straits patrol mission.

[Preparation of fuel consumption estimation]
(1)External fuel tank capacity estimation
This diagram indicates that external fuel tank capacity is approx. 200kL.
http://blog.livedoor.jp/wispywood2344/others/Soryu_External_Fuel_Tank.png
I assumed that initial fuel loadage is 190kL.

(2)Engine specific fuel consumption
The value of specific fuel consumption of 12V25/25S is unknown.
So, I assumed it to be the same to MTU 16V396SE84. (280g/kWh)
http://www.bmtdsl.co.uk/media/6097995/BMTDSL-Sub-Power-and-Propulsion-Confpaper-Pacific-Jan12.pdf#page=3

(3)Generator efficiency
Rated shaft output of 12V25/25S is 2700ps (=1986kW), and rated electric output of SG-6 is 1850kW.
Therefore generator efficiency is 93.2%(=100*1850/1986).

(4)AIP endurance estimation
Done in my blog article(japanese language)
http://blog.livedoor.jp/wispywood2344/archives/54964300.html

(5)Motor power vs ship speed relationship estimation
Done in my blog article(japanese language)
http://blog.livedoor.jp/wispywood2344/archives/55480697.html
Mainly based on "General rule for Submarine Electrical Propulsion System -- Part2 : AC-motor-propelled submarines".
http://www.mod.go.jp/atla/nds/F/F8004_2.pdf#page=38

(6)Hotel load estimation
Total power consumtion in AIP submerge is 240kW, and propulsion power consumotion is 77.7kW.
Therefore AIP hotel load is 162kW.
http://www.mod.go.jp/atla/nds/F/F8004_2.pdf#page=38
Additional AIP load (such as exhaust pump) is assumed to approx.10kW, basic hotel load is 152kW.
Additional snort load is considered to be propotional to engine shaft output.
The constant of propotionality is the same as this paper (additional snort load is as 0.0458 times as engine shaft power).
http://www.bmtdsl.co.uk/media/6097995/BMTDSL-Sub-Power-and-Propulsion-Confpaper-Pacific-Jan12.pdf

(To be continued)

Wispywood2344 said...

[Estimation of fuel consumption]
(1)Transit phase (From Yokoska naval base to La Pérouse Straits)
See below
http://blog.livedoor.jp/wispywood2344/others/Phase1.png

(2)Patrol phase
See below.
http://blog.livedoor.jp/wispywood2344/others/Phase2.png

(3)Transit phase (From La Pérouse Straits to Yokoska naval base)
See below
http://blog.livedoor.jp/wispywood2344/others/Phase3.png

In this mission, total operational duration is up to 80days(=4.3+57.2+14+4.3), approximately 3 months.

Regards
Wispywood2344

Peter Coates said...

Hi Wispywood2344 [at 14/4/16 10:30 PM and 14/4/16 10:32 PM]

Most interesting calculations.

As the Collins (at 11,500nm) has a much longer range than the Soryu Collins crews should feel relaxed about performing far longer missions - say

150 DAYS?

As long as they don't get at all tired and go on strict diets...

Cheers

Pete