Retired Vice Admiral Masao Kobayashi commanded Japan’s submarine fleet from 2007 to 2009. In a recent interview in Tokyo with The Japan Times, when asked to explain one of the country’s most tightly guarded military secrets, he seemed reflective.
Kobayashi pointed to the ceiling lights in the quiet interview room and said: “Take those fluorescent lights, for example. Any fluorescent light generates sound.”
Other than our voices, there were no other sounds in the room.
“Fluorescent lights generate extremely small vibrations. We take anti-vibration measures for every single light in a submarine,” he said.
Japan’s engineers have painstakingly worked to minimize the vibrations given off by the multitude of components in submarines to prevent even those undetectable by the human ear from being picked up by the super-sensitive sonars of enemy subs and sonobuoys from anti-submarine aircraft, Kobayashi said.
Noisy components include fans, pumps, motors and fluorescent lights. Some are carefully muted with vibration-damping rubber, he said.
“The quiet submarines we have today are the result of numerous long, patient efforts,” Kobayashi said.
The Maritime Self-Defense Force’s submarines are not nuclear-powered but have a reputation for being ultra-quiet.
Now Australia, seeking to build a new fleet of large, long-range submarines, seems keen on acquiring Japan’s latest Soryu-class subs, or at least their technology.
If the deal goes through, the top-secret submarines will become the first major pieces of military hardware Japan has authorized for export since the administration of Prime Minister Shinzo Abe lifted the decades-long blanket ban on arms sales last year.
Vice Adm. Robert Thomas, commander of the U.S. Navy’s 7th Fleet, reportedly said Oct. 24 in Tokyo that then-Australian Defense Minister David Johnston was very interested in Japan’s Soryu-class subs.
“I talked to him about it four years ago and I said: ‘You want to find the finest diesel-electric submarine made on the planet — it’s made at Kobe works in Japan,’ Thomas was quoted as saying by Bloomberg News.
The U.S., which has close but separate security pacts with Japan and Australia, probably wants Australia to buy Japanese submarines because it would greatly strengthen their strategic military ties, Kobayashi said.
Deeper Japan-Australia military cooperation would help ease the heavy burden on the U.S. fleet, which is busy decommissioning many of the nuclear-powered attack submarines it built during the Cold War, he said.
“The U.S. rapidly built many Los Angeles-class nuclear submarines during the Cold War. Many of them are being decommissioned now,” Kobayashi said.
“I think the U.S. wants to create a strategic triangle of Japan, Australia and the United States. That’s probably a factor behind” the apparent U.S. nod to Australia’s proposal to Japan, he added.
Japanese defense officials are thought to be pleased for the same reason Washington is. They want to deepen strategic military ties with Australia.
“Australia would make a good partner for cooperation. There are no major diplomatic problems between the two countries other than whaling,” a senior Defense Ministry official said on condition anonymity. Australia opposes Japan’s annual whaling expeditions.
Japan has just started receiving the submarine specifications sought by Australia but has yet to decide which secrets to share, two senior defense officials said.
Japan soon plans to use lithium-ion batteries to drive the motors in its latest Soryu sub, making them even quieter. Australia is believed to be interested in this advance, the officials said.
But advanced lithium-ion batteries are one of Japan’s top military secrets, one warned.
“(Exporting) them would be a rather sensitive issue. We’d need to study if it’s really appropriate for an outside party (to have that technology),” the Defense Ministry official said.
In Australia meanwhile, opposition lawmakers and trade unions are strongly opposed to procuring Japanese submarines because it could considerably undermine the domestic defense industry and reduce jobs in South Australia.
Joint development might be an option, the two Japanese officials said, noting that nothing concrete has been officially proposed.
Teruhiko Fukushima, a professor at the National Defense Academy in Yokosuka, Kanagawa Prefecture, who is an expert on Australia, said Prime Minister Tony Abbott seems eager to procure the subs to bolster Canberra’s military ties with Japan and the United States.
“Abbott should be considering a Japan-U.S.-Australian alliance as a kind of insurance” against the recent rise of China’s powerful military, Fukushima said.
“The introduction of Soryu-class submarines would be a plus to strengthen that alliance,” he added.
“If the Abbott administration survives the next election and wins a second term, there will be a greater chance that Soryu-class submarines will be introduced in Australia,” he said.
Last June, Australia and Japan conducted “two-plus-two” talks between their foreign and defense ministers.
In the joint statement that followed, Australia expressed “strong opposition to the use of force or coercion to unilaterally alter the status quo in the East China Sea and the South China Sea,” an apparent warning to China to not aggressively press its territorial claims in those areas, which include the Japan-controlled Senkaku Islands, which China and Taiwan also claim. China calls the uninhabited islets Diaoyu and Taiwan calls them Tiaoyutai.
Fukushima also said that on Nov. 26, 2013, only three days after Beijing declared the establishment of an air defense identification zone over the East China Sea that included the Senkakus, the Abbott administration summoned the Chinese ambassador in Canberra to express its concerns after the ADIZ drew strong protests from Tokyo and Washington.
“There is no doubt Abbott puts great emphasis on the relationship shared by Japan, the U.S. and Australia,” Fukushima said.
But he also noted that China is Australia’s No. 1 trade partner and that the public would never approve of political actions that could seriously damage those economic ties.
“The best way for Abbott is to strengthen the Japan-U.S.-Australian relationship while maintaining good economic ties with China at the same time. Australia would never turn its back on the Chinese market,” he said.