German submarine Hai, the former U-2365 Type XXIII U-boat of Nazi Germany's Kriegsmarine during World War II, was one of the first submarines of the Bundesmarine. She was ordered on 20 September 1944, and was laid down on 6 December 1944 at Deutsche Werft AG, Hamburg, as yard number 519. She was launched on 26 January 1945 and commissioned under the command of Oberleutnant zur See Fritz-Otto Korfmann on 2 March 1945. Scuttled in 1945, the boat was raised in 1956 and commissioned into the newly-founded Bundesmarine as Hai, where she served until she sank by accident in 1966.