Which World War II submarine sank the Japanese aircraft carrier Shinano in 1944?

USS Archerfish sank the Japanese aircraft carrier Shinano in 1944.

Archerfish attacked Shinano on 29 November 1944, about ten hours after the Japanese carrier had begun its first voyage from Yokosuka. The submarine fired a spread of torpedoes and struck the ship four times. Shinano capsized and sank roughly seven hours later.

Shinano had begun as a Yamato-class battleship but was converted into an aircraft carrier after Japan’s naval losses at Midway. It was the largest aircraft carrier ever built at the time, making its loss especially significant.

Archerfish’s target was initially unidentified; the submarine’s crew recognized it as an unusually large carrier only after the attack. The engagement is remembered as one of the most dramatic submarine victories of the Pacific War.