Soryu class submarine SS-506 "Kokuryu" being built at the KHI shipyard in Kobe, Japan. SS-506 was commissioned in March 2014.
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At http://gentleseas.blogspot.com.au/2015/08/7-problems-with-japanese-option.html in Comments on August 23, 2015 at 11:42 AM a Japanese representative (possibly from the Japanese Ministry of Defence) responded to Australian Made Defence’s "7 Problems [Questions in red] With The Japanese Option" I have asked follow-up questions at 2 and 6.
Question 1 “What are the risks?”
Japanese Response:
1-1) Hull stability and operation temperature
The pressure hull is designed for [operational temperature ranges of] ca. -30C to ca. +50C. This temperature range does not depend on country. [Information from China, Russia and Australia is within that] temperature range. [Adaptation of a cold water-hull to warm water conditions is not a problem. Rather a greater concern would be hull steel brittleness if a hull designed for warm water is used in cold water].
1-2) Modification [to increase operational] range
For increasing of operation range, hull must be elongated [lengthened] for carrying extra fuel. The Soryu is the hull elongation [lengthened] version of Oyashio, but there are no problem related to hull elongation.
Question 2 ”Will Australia have to pay for the development of a new shipyard and workforce in Japan to build it submarines?”
Japanese Response:
In the case of knock-down production, I do not think that additional new shipyard is required.
Pete follow-up question: What does “knock-down production” in the case of a new submarine mean?
Question 3 ”How long do Japanese submarines last?”
Japanese Response:
Design and building of submarine may be optimized for achieving given submarine life based on modern quality control concepts. If submarine user requires a longer life-time, the design and building will be optimized again. But, I do not think that it will not be a big modification, because the safety factors are considered well in the original 15 years-operation submarine.
Question 4 ”What will be Australia’s capacity to sustain submarines built in Japan?”
Japanese Response:
If new hull material is developed by a [Australian-Japanese corporation] Australia and Japan will share the related intellectual properties according to contribution.
Question 5 ” Can the hulls be built in Japan and fitted-out in Australia?”
Japanese Response:
[A] modular building system is adopted for the current Soryu submarine. Beside hull welding-connection work, involvement of Australian manufacturers in constructing and installation of each module will be important issue, too.
Question 6 “ How do we go in times of trouble?”
Japanese Response:
Trouble related to black box will be fixed in Japan or by Japanese experts.
Pete follow-up question:
What does “black box” mean?
Question 7 ”Will we repeat the problems of the past?”
Japanese Response:
The Japan lacks experience of arm export. But, many companies involved in Japanese submarine building are very famous and first class, they export their products and some of them have foreign branches."
Pete
Pete