Name I-401 Construction started 26 April 1943 Length 122 m | Commissioned 8 January 1945 Beam 12 m (39 ft) Launched 11 March 1944 | |
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Fate Surrendered to USS Segundo, 29 August 1945Expended as a target ship, off Pearl Harbor, 31 May 1946 Displacement 5,223 long tons (5,307 t) surfaced6,560 long tons (6,665 t) submerged | ||
The Sen Toku-class I-401 (伊号第四百一潜水艦) was once the largest submarine in the world. It was commanded by Lieutenant Commander Nobukiyo Nambu of the Imperial Japanese Navy during World War II. Capable of carrying three two-seat Aichi M6A1 "Seiran" (Mountain Haze) float torpedo bombers, the Sen Tokus were built to launch a surprise air strike against the Panama Canal.
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Service history
When I-401 was completed and commissioned on 8 January 1945 in the Kure Naval District, the Second World War was almost over. This left the fate of I-401 uncertain. After several attempts to launch, I-401 set course for its first target, but was stopped by Emperor Hirohito's broadcast, calling for an end to all hostilities on 15 August 1945.
On 26 August 1945, I-401 hoisted a black flag of surrender. Its unmanned planes were catapulted into the sea, all 20 Type 95 torpedoes were destroyed, and all codes, logs, charts and secret documents were also destroyed.
Three days later, on 29 August 1945, I-401 was picked up on USS Segundo's radar. I-401 surrendered to the US ship. Lieutenant Commander Nobukiyo Nambu delivered two katana, as a symbol of surrender, to Lieutenant John Edward Balson, Segundo's Prize Crew officer.
I-401 was finally sunk, when used as a target ship, off Pearl Harbor on 31 May 1946.
Rediscovery
On 17 March 2005, the Hawaii Undersea Research Laboratory's (HURL) deep-diving submersibles Pisces IV & Pisces V located I-401 off the coast of Kalaeloa. I-401 lies about 820 metres (2,690 ft) off the coast of Barbers Point. The bow is broken off just forward of the aircraft hangar. The two pieces are not far apart and are connected by a debris field. The main hull is sitting upright on the bottom, the numbers "I-401" are clearly visible on the sides of the conning tower. Her 25 mm anti-aircraft guns seem in almost perfect condition.