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SECRETS OF THE DEAD: Japanese SuperSub

Airs Wednesday, February 29, 2012 at 10 p.m. on KPBS TV

One of two I-400s under sail.

Credit: National Archives & Records Administration (NARA)

Above: One of two I-400s under sail.

In spring of 1946, ten months after the end of World War II, an explosion rocks the Pacific off the coast of Hawaii. America has just destroyed one of Japan’s most advanced weapons systems — the I-401 aircraft carrier submarine. But this was no belated attack against the defeated Japanese. Bound by an agreement to share any discoveries with the Soviets, but feeling the pressure of the looming cold war, it was a calculated decision to keep the technology out of Soviet hands.

Japanese SuperSub Gallery

Browse images related to "Japanese SuperSub" including photos of the original Japanese and United States naval crews, stills from animated renderings of the I-400 in action, and the final moment of surrender when the sub was captured.

The Japanese had built their sub to take the war to U.S. shores. Merging the stealth and tactical advantages of sea and sky, the revolutionary submarine carried three specially designed Seiran attack bombers, which could be launched from the deck of the sub within seven minutes of its reaching the surface.

With missions to attack U.S. cities and blow up the Panama Canal, the aircraft carrier submarine had the potential to change the course of the war in the Pacific. But fortunately for America, its secret weapon — the atom bomb — was put into action first.

“Japanese SuperSub” investigates Japan’s efforts to take submarine technology where it had never gone before, and reveals how close the Japanese came to using the sub for an attack on the U.S.

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Secrets Of The Dead: Japanese SuperSub

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Watch Japanese SuperSub on PBS. See more from Secrets of the Dead.

"Japanese SuperSub" recounts Japan's superior submarine technology and reveals how close the Japanese came to using the subs to blow up the Panama Canal, terrorize the U.S. and possibly enact a deadly biological attack. The film premieres nationally Wednesday, May 5, 2010.

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