Australia's Defence Minister, Marise Payne, working quietly on the 2016 Defence White Paper and on the Submarine Winner Decision. (Photo courtesy AAP)
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David Wroe in the Sydney Morning Herald (SMH), February 9, 2016, reports http://www.smh.com.au/federal-politics/political-news/malcolm-turnbull-leaning-towards-fullstrength-fleet-of-12-submarines-20160209-gmpiel.html:
"The Turnbull government is leaning strongly towards building a
full-strength fleet of 12 submarines rather than the reduced fleet of eight
boats the Coalition was previously considering.
...But it is understood that given the advantages of creating a
large and permanent submarine workforce, the need to honour the Abbott-era
promise and the strategic uncertainty Australia faces in the Asia-Pacific
region in the decades to come, the Turnbull government is inclined to commit to
the full 12 boats in the revamped white paper.
That
major defence statement, which will lay out the nation's security plans for the
next decade, is [Defence White Paper] due
to be released next month.
COMMENT
I would say Australia will end up with 8 x Japanese designed subs, but with an option (never taken up) of 4 more. We are working with such long lead times that long terrm government promises made in 2016 count as nothing in 2026.
A promise of "12" amounts to a good "continuous build" political promise in Adelaide.
A promise of "12" amounts to a good "continuous build" political promise in Adelaide.
Australia's ongoing struggles to find sufficient submarine commanders and crew for even 2 (of 6) submarines available for action at any one time certainly mitigates against making 12 submarines a viable and economical number.
Pete
Pete
11 comments:
Hi Pete
In the project planning, we must prepare needed resources (money, equipment, technology, personnel, etc.). Unless sufficient resources are provided, the effective planning is never conducted. Current situation, i.e. continued shortage of crews, is really surprising. It seems that there is serious defect in the management of the project planning of submarine.
ASC is heavily criticized for bad performance of the Collins submarines, but Australian Ministry of Defense is finally responsible.
Prevention from leakage of submarine technology is one of the most important issues for Japanese tax payers and submariners. I do not think that AUS MoD can currently manage or reduce the security risk well. But, if they realize this situation and try to improve, worst results might be avoided. If there is problem, they should contact US or Japan, never hide.
I do not have any bad feeling to Australia, but I must say something, because we are already stakeholders whether we hope or not.
Regards
S
Hi S
Yes every time the Australian Government holds a review of the Collins and identifies improvements with the Collins Program it is the lack of crew that remains a key problem that comes back to haunt each Australian Chief of Navy and his Defence Minister.
Probably best that Japan not share its highest specification NS110 steel with Australia.
1. NS110 is too sensitive secret leaking wise.
2. Australians ability to weld NS110 will be a skill hard for Australia to develop and maintain, and
3. The very deep dive cycle performance of NS110 reduces hull life shorter than the 30 years Australia's Navy and taxpayers expect. This is even if ASC - Adelaide would prefer to build 12 x limited 20 year life submarines instead of 8 x 30 year life subs.
Regards
Pete
Hi Pete
Repeated applied stress causes the crack generation and propagation (= fatigue) in a material. The applied stress relates to logarithm of repeated number of the stress (Log N, N is repeated number). In the case of 10 times diving per day, total diving number for 22 years operation is 80,000 (Log N=4.9), and that for 30 years operation is 110,000 (Log N =5.0). The difference in between two Logs is only 0.1 (=5.0-4.9), which is within error of measurement of mechanical strength.
Fatigue is irreversible process and finally causes fracture of materials, but steel or titanium does not experience fatigue under a certain value of stress (=fatigue limit). Safety factor (SF), the structural capacity of a system beyond the expected stresses or actual stresses is also adopted for structure design. Hull design and operational conditions of submarine are decided by considering various factors including fatigue limit and SF. I think that JMSDF monitors and records diving number and depth to ensure safety of submarine.
Other effects including corrosion should be considered for long term operation. As NS-110 was adopted for Harushio-class submarine which was precedent of Oyashio-class submarine, huge important experimental data are accumulated. I think JMSDF continues very long period immersion testing of hull steel to measure corrosion behavior.
Regards
S
Assuming the operating conditions of the submarine is set with a design factor well within the fatigue design limits, there should not be an issue with crack generation and propagation.
The same goes with corrosion. Assuming that the design takes into account the material loss over time (assuming the material properties are well characterized) from sea water corrosion over the submarine lifetime, and there is no standing water inside the hull, then corrosion should not be an issue.
KQN
Hi KQN
This submarine operational life issue is complicated by Japan's MoD/MHI/KHI industrial practice of continuous build which guarantees that one submarine will be built per year.
Japan has had a fairly rigid policy of decommissiong its subs after 18 years - starting from the Ooshio class in 1965 http://gentleseas.blogspot.com.au/2015/01/history-of-japanese-submarine-after-wwii.html
But now Japan is growing its submarine numbers to 22 operational to meet the N Korean/Chinese submarine threat. I think Japan is doing this by extending the lives of its Oyashio subs (which precedes the Soryus) from 18 years to 22. Maybe this will mean 22 year operational lifes for each Japanese submarine from now on.
This may mean Aussie "Super Soryus" can expect a 22 year life, but not the 30 years we're used to.
Regards
Pete
Hi Pete
Corrosion is a very serious issue in marine industry or Navy and is classified uniform corrosion and local corrosion
Uniform corrosion is observed for low corrosion resistant materials such as carbon steel. Uniform corrosion progresses homogenously at constant rate, and we can handle this corrosion by setting corrosion margin. If the corrosion rate is 1mm/year, we can protect for 30 years by setting 30mm of corrosion margin.
Local corrosion (pitting, crevice corrosion, stress corrosion cracking (SCC), etc.) is observed for high corrosion resistant materials such as austenite stainless steel. As local corrosion progresses heterogeneously, uncorroded and corroded areas are separated clearly and provide serious damage to materials.
Pitting progresses along thickness direction.
Crevice corrosion progress in a crevice between materials.
SCC is caused by stress and corrosion.
The hull situation should be monitored and important data should be collected to prevent disastrous damage.
In the case of fatigue, this phenomenon under normal and simple condition will be controlled. But, use under critical condition such near crusher depth or actual condition of mixed fatigue and corrosion should be considered. This mechanical situation should be monitored.
Combination of NS-100 and gas tungsten arc weld is best for hull architecture of Aussie Super Soryus, because the combination provide not only the strongest hull but also the highest operation safety and reliability based on 25 years monitoring/data collection & analysis and long incubation period of NS-110 development. So the key issue in the submarine deal is the technology protection, and money is in the secondary position.
In the technology transfer, Australia and Japan must discuss whether China can achieve this reliability or not, and how to protect the secret technology. Many people like to show confidence without foundation, but such confidence causes significant anxiety.
Regards
S
Is the 18-22 year life of a Japanese sub actually something truly limited by its materials and design or is it simply an arbitrary number chosen for political reasons due to the annual production rate? Minimally it seems like the life of a ship or sub is not as specific as '18 years', and clearly the Oyashio class is going to remain in service longer than 18 years despite hypothetically not being designed for such. The number and depth of the dive cycles seems to set the absolute limit of how long a sub can see service; are there hard numbers for Collins and Oyashio/Soryu that can be compared? RAN boats can definitely expect more time at sea due to transit times to get on station, BUT this time will largely be spent at periscope depth. Patrol for Patrol I'd not expect a RAN boat to commit to more dives than its JMSDF counterpart.
Cheers,
Josh
Hi S [at 13/2/16 12:12AM]
Japanese, French and German submarine steel is on this table http://gentleseas.blogspot.com.au/2015/07/chinese-and-russian-submarine-pressure.html .
I'm assuming from your concentration on submarine steel corrossion that this may be a life limiting factor for Japanese submarine hull steel.
This is a difficult topic that Australian politicians in National Security Committee of Cabinet may not understand when they choose the Soryu.
I also assume different hull steel formulas corrode (and rust?) at different rates. eg TKMS 216 steel compared to Super Soryu steel.
Regards
Pete
Hi Josh
Given Japan sets the number of operation submarines (was 16-18 now 22).
Japan then calculates that to keep its MHI and KHI submarine building labour force fully and efficiently employed building one submarine a year ("continuous build") is optimal.
So the submarine life (in years) coincides with the number of operational submarines.
As the Japanese Ministry of Defence and Navy know that a sub is meant to last 22 years, they can adjust submarine steel life (influencing number of dive cycles) and engine life accordingly.
Midlife and other periodic inspections of Oyashio and Soryu's steel (which S referred to at at 13/2/16 12:12AM) can (or should) give Japan enough confidence to extend the life from 18 to the 22 year target.
Areas like electronic hardware is more variable, more frequetly upgraded and software upgraded-improved even more often.
Overall Japan improves subs within each class (like Oyashio and Soryu) and makes even larger improvements with each succeeding class. See Oyashio and Soryu build table here http://gentleseas.blogspot.com.au/2016/01/japanese-submarine-costings-oyashios.html
Regards
Pete
Hi Pete
Thickness of pressure hull is from 45mm to 65mm regardless operation period, and thinness out of thinness is not desirable. Maximum thickness of N-110 is specified 65mm and structures of Japanese submarine is optimized to keep highest strength, but its operation period (18 years) is much shorter than that of other Navy which is usually over 30 years. If the degradation of the pressure hull determines operation period, the hull life extension from 18 years to 22 years is technological acrobats.
The operation period of Japanese submarine is much longer than 18years and is comparable to that other nation’s submarine. The 18 years-operation period is not decided based on the hull degradation but psychology of Ministry of Defense (MOD). We must understand psychology of military men. They always emphasize aging of their own weapons and superiority of enemy’s equipment to get latest weapons. Soryu is the case. If MOD says the operation period is more than 30 years, Ministry of Finance (MOF) never admits every 16 years-update of submarine and says wait for 30 years.
Although many Australians have repeatedly pointed out the short operation period of Soryu, MOD keeps silence on this influential issue. MOD well understands that silence is gold.
Regards
S
Before correction
Thickness of pressure hull is from 45mm to 65mm regardless operation period, and thinness out of ”thinness” is not desirable. Maximum thickness of N-110 is specified 65mm and “structures” of Japanese submarine is optimized to keep highest strength, but its operation period (18 years) is much shorter than that of other Navy which is usually over 30 years. If the degradation of the pressure hull determines operation period, the hull life extension from 18 years to 22 years is technological “acrobats”.
After correction
Thickness of pressure hull is from 45mm to 65mm regardless operation period, and thinness out of this range is not desirable. Maximum thickness of N-110 is specified 65mm and structure of Japanese submarine is optimized to keep highest strength, but its operation period (18 years) is much shorter than that of other Navy which is usually over 30 years. It is quite strange. If the degradation of the pressure hull determines operation period, the hull life extension from 18 years to 22 years is technological acrobat.
S
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