German submarine Hai (S 170)

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 on 8 May 1945, the boat was raised in June 1956 and commissioned into the newly founded Bundesmarine as Hai, where she served until she sank by accident on 14 September 1966.

Design
Like all Type XXIII U-boats, U-2365 had a displacement of 234 t when at the surface and 258 t while submerged. She had a total length of 34.68 m (o/a), a beam width of 3.02 m (o/a), and a draught depth of 3.66 m. The submarine was powered by one MWM six-cylinder RS134S diesel engine providing 575 - 630 PS, one AEG GU4463-8 double-acting electric motor electric motor providing 580 PS, and one BBC silent running CCR188 electric motor providing 35 PS.

The submarine had a maximum surface speed of 9.7 kn and a submerged speed of 12.5 kn. When submerged, the boat could operate at 4 kn for 194 nmi; when surfaced, she could travel 2600 nmi at 8 kn. U-2365 was fitted with two 53.3 cm torpedo tubes in the bow. She could carry two preloaded torpedoes. The complement was 14 – 18 men. This class of U-boat did not carry a deck gun.

Service history
On 8 May 1945, U-2365 was scuttled northwest of Anholt in the Kattegat as part of Operation Regenbogen. The wreck was originally located at 56.85°N, 11.81667°W.

Post war service
In June 1956, U-2365 was raised by the German Federal Navy and commissioned Hai on 15 August 1957. On 14 September 1966, she foundered on Dogger Bank in the North Sea during a gale. Nineteen of the twenty crewmen were lost, making this one of the worst peacetime naval disasters in German history. She was raised on 19 September 1966 from 47 m of water and broken up.

The wreck was located at 55.25°N, 4.36667°W.