The Admiral in charge of planning for Australia's next generation of submarines and the chief defence scientist are studying an advanced new submarine in service with the Japanese navy.
Rear-Admiral Rowan Moffitt, head of the Royal Australian Navy's Future Submarine Program, and Dr Alexander Zelinsky, the Chief Defence Scientist, travel to Japan this month to look at the Soryu-class submarines, which started service with the Japan Maritime Self-Defence Force three years ago.
Submarines no longer all at sea
Access to the Soryu technology was discussed during a visit to Australia last month by the Japanese navy's chief, Admiral Masahiko Sugimoto. It was only in December that Tokyo lifted its post-World War II embargo on defence exports.
The 4200-tonne Soryu-class boats are the only new conventional submarines of the size and capabilities set out in Canberra's 2009 defence white paper for 12 new submarines to take over from the Collins-class subs from the late 2020s.
''Our strategy with the Japanese is one of hope, because there are some very attractive characteristics about the Japanese submarine,'' Rear-Admiral Moffitt said.
As well as having a close alliance relationship with the United States similar to Australia's, Japan's navy operated in the same Asia-Pacific environment, which was reflected in its submarine design, he said.
''Their submarine, by all accounts, and their design and the evolution of that design, has by all accounts brought them to the point of having a very good submarine,'' Rear-Admiral Moffitt said.
''However, submarine technology tends to be crown-jewel stuff for nations, it tends to be at the most extreme end of sensitivity that nations have about protecting their intellectual property - especially if they have developed it themselves, as Japan has, as the US has. They've invested a vast amount of money doing that.''
Under a $214 million allocation in this year's budget, the RAN has stepped up work on selecting the new submarine design. Four options are: Adapting an existing ''military off the shelf'' or MOTS submarine, a large ''evolved MOTS'' design, an evolution of the Collins class, and a completely new Australian design.
Until the Soryu became theoretically available, off-the-shelf submarines included only German, French and Spanish designs of about 2000 tonnes.