German submarine U-864

History
Nazi Germany
Name	U-864
Ordered	5 June 1941
Builder	DeSchiMAG AG Weser, Bremen
Yard number	1070
Laid down	15 October 1942
Launched	12 August 1943
Commissioned	9 December 1943
Fate	Sunk with all hands on 9 February 1945 by HMS Venturer, North Sea west of Bergen
General characteristics
Class and type	Type IXD2 submarine
Displacement	1,610 t (1,580 long tons) surfaced 1,799 t (1,771 long tons) submerged
Length	87.58 m (287 ft 4 in) o/a 68.5 m (224 ft 9 in) pressure hull
Beam	7.50 m (24 ft 7 in) o/a 4.40 m (14 ft 5 in) pressure hull
Height	10.20 m (33 ft 6 in)
Draught	5.35 m (17 ft 7 in)
Propulsion	9,000 PS (8,900 shp; 6,600 kW) surfaced 1,000 PS (990 shp; 740 kW) submerged
Speed	20.8 kn (38.5 km/h; 23.9 mph) surfaced 6.9 kn (12.8 km/h; 7.9 mph) submerged
Range	12,750 nmi (23,610 km; 14,670 mi) at 10 kn (19 km/h; 12 mph) surfaced 57 nmi (106 km; 66 mi) at 4 kn (7.4 km/h; 4.6 mph) submerged
Test depth	Calculated crush depth: 230 m (754 ft 7 in)
Boats & landing craft carried	2 dinghies
Complement	55–63 officers & ratings
Armament	6 × torpedo tubes (four bow, two stern) 24 × 53.3 cm (21 in) torpedoes 1 × 10.5 cm (4.1 in) SK C/32 deck gun (150 rounds) 1 × 3.7 cm (1.5 in) Flak M42 AA gun 2 × 2 cm (0.79 in) C/30 anti-aircraft guns
Service record
Part of:	4th U-boat Flotilla 9 December 1943 – 31 October 1944 33rd U-boat Flotilla 1 November 1944 – 9 February 1945
Identification codes:	M 54 842
Commanders:	K.Kapt. Ralf-Reimar Wolfram 9 December 1943 – 9 February 1945
Operations:	1 patrol: 7 – 9 February 1945
Victories:	None

German submarine U-864 was a Type IXD2 U-boat of Nazi Germany's Kriegsmarine in World War II. On 9 February 1945, she became the only submarine in history to be sunk by an enemy submarine while both were submerged. U-864 was sunk by the British submarine HMS Venturer, and all 73 men on board died.