Shinano

1944

Maiden voyage, seven hours, USS Archerfish Location: Pacific Ocean, south of Honshu, Japan · Coordinates: 33.27°N 137.07°E · Casualties: 1,435 · Survivors: 1,080 · Depth: 4,000 m · Cause: submarine torpedo — Torpedoed by the American submarine USS Archerfish (Joseph Enright, commanding) four times between 03:17 and 03:20 on 29 November 1944, seventeen days after commissioning, on her maiden voyage from Yokosuka to Kure. Watertight bulkheads were unfinished; pumps were inadequate. Capsized and sank seven hours later. · Fate: abyssal · not located · Type: aircraft carrier · converted Yamato class · Tonnage: 72,000 tons · Crew: 2515 · Flag: Empire of Japan · Launched: 1944 Originally laid down as the third Yamato-class battleship, converted mid-build to an armoured aircraft carrier, the largest warship ever built at the time. Sailed from Yokosuka on her maiden voyage only seventeen days commissioned; torpedoed four times by USS Archerfish on the morning of 29 November 1944. Poor damage control and unfinished watertight bulkheads doomed her. Sank seven hours after her first torpedo, on her first voyage. 1,435 dead. The Vessel The Imperial Japanese Navy aircraft carrier Shinano was the largest warship ever built until the commissioning of the American nuclear carrier USS Enterprise (CVN-65) in 1961. She was laid down as the third of the Yamato-class battleships on 4 May 1940 at the Yokosuka Naval Arsenal, but was converted during construction into an aircraft carrier following the destruction of the four Midway carriers in June 1942. She was commissioned on 19 November 1944. The conversion from battleship to carrier had been approved in June 1942 and began in June 1943 under the immediate pressure of Japanese fleet carrier losses. The resulting ship displaced 72,000 tons, was 266 metres long, and had a flight deck capable of operating 47 aircraft. Her armour scheme was retained from her battleship design: she had the thickest flight-deck armour of any aircraft carrier ever built (190 mm), and her belt armour remained the 410 mm of the Yamato-class. Her operational concept was unusual. The 1944 Imperial Japanese Navy carrier doctrine had, by that stage of the war, evolved toward the use of large carriers as support bases for land-based aircraft rather than as direct strike platforms. Shinano was intended to operate as a forward-deployed fleet carrier that would service, rearm, and refuel carrier aircraft and land-based bombers operating from bases in the Philippines, Formosa, and the Japanese home islands. Her large aviation fuel capacity (3,300 tons) and her ability to carry approximately 120 disas The Disaster Enright fired a full six-torpedo bow spread at 03:17 on 29 November 1944. Four of the six torpedoes struck Shinano on her starboard side, in a cluster between her Frame 120 (the aft engine room) and Frame 180 (her after aviation fuel tanks). The four torpedo hits breached approximately 15 per cent of her hull side protection. Shinano's damage control was catastrophic. Her internal subdivision was incomplete because of her rushed commissioning: the watertight door seals in her engineering spaces had not been fitted to the intended tightness, her counter-flooding pumps had not been fully tested, and her damage-control teams had not been drilled in her specific internal layout. The flooding of her engine rooms, which her design had been calculated to contain, instead propagated through adjacent compartments that should have been watertight but were not. By 06:00 on 29 November 1944 Shinano had a 9-degree list to starboard. By 08:00 the list had increased to 13 degrees. By 09:00 her engine rooms were fully flooded and she was making 10 knots through the remaining engine; at 09:30 this speed dropped to 6 knots as her main boiler room flooded. Captain Abe ordered a course change toward Shiono-misaki, the nearest coast, in an attempt to beach her. The list continued to increase through the following hours. At 10:55 on 29 November 1944, Shinano rolled onto her starboard side. She capsized at 11:00. She sank, stern-first, at 11:17 on 29 November 1944 at approximately 33°07′N 137°04′E