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 Kusaka, Ambassador 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.
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:
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
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
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)
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).
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
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
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
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
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.
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)
[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
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
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