Submarines of the Imperial Japanese Navy
The IJN submarine arm did have a number of notable successes against American warships, however. During the Battle of Midway, administered the final "coup de grace" that sank the fleet carrier , as well as sinking the destroyer . A few months later, on September 15, 1942, with a single salvo of torpedoes, Japanese submarine sank the fleet carrier and damaged both the battleship and the destroyer . On November 13, 1942, the submarine torpedoed and sank the anti-aircraft cruiser , and a year later on November 23, 1943 the submarine torpedoed and sank the escort carrier , both with heavy loss of life. The had the distinction of both severely damaging the heavy cruiser , knocking her out of the war for a year, on October 20, 1942, and of also sinking (the only American submarine to be sunk by a Japanese submarine in the entire war) on November 16, 1943.
Japanese submarine I-55 (1925)
Following World War I, the Imperial Japanese Navy re-evaluated the use submarine warfare as an element of fleet strategy due to the successful deployment of long-range cruiser-submarines for commerce raiding by the major combatant navies. Japanese strategists came to realize possibilities for using the weapon for long range reconnaissance, and in a war of attrition against an enemy fleet approaching Japan. Two large, long-range Japanese submarines had already been built under the Eight-six fleet program as prototype ( and ), however, the arrival on 20 June 1919 of seven German U-boats received by Japan as war reparations at the end of World War I led to a complete re-design. The Japanese quickly hired hundreds of German submarine engineers, technicians and former U-boat officers unemployed by the defeat of Germany in World War I, and brought them to Japan under 5-year contracts. The American ONI (Office of Naval Intelligence) estimated that some 800 German advisors had gone to Japan by the end of 1920. The Japanese also sent delegations to Germany, and were active in purchasing many patents.