History
Nazi Germany
Name	U-3031
Ordered	6 November 1943
Builder	AG Weser, Bremen
Yard number	1190
Laid down	30 October 1944
Launched	6 January 1945
Commissioned	28 February 1945
Fate	Scuttled on 3 May 1945
General characteristics
Class and type	Type XXI submarine
Displacement	1,621 t (1,595 long tons) surfaced 1,819 t (1,790 long tons) submerged
Length	76.70 m (251 ft 8 in) (o/a) 60.50 m (198 ft 6 in) (p/h)
Beam	8 m (26 ft 3 in) (o/a) 5.3 m (17 ft 5 in) (p/h)
Height	11.30 m (37 ft 1 in)
Draught	6.32 m (20 ft 9 in)
Installed power	4,000 PS (2,900 kW; 3,900 shp) (diesel drive) 5,000 PS (3,700 kW; 4,900 shp) (standard electric drive) 226 PS (166 kW; 223 shp) (silent electric drive)
Propulsion	Diesel/Electric 2 × MAN M6V40/46KBB supercharged 6-cylinder diesel engines 2 × SSW GU365/30 double-acting electric motors 2 × SSW GV232/28 silent running electric motors
Speed	Surfaced: 15.6 knots (28.9 km/h; 18.0 mph) (diesel) 17.9 knots (33.2 km/h; 20.6 mph) (electric) Submerged: 17.2 knots (31.9 km/h; 19.8 mph) (electric) 6.1 knots (11.3 km/h; 7.0 mph) (silent running motors)
Range	15,500 nmi (28,700 km; 17,800 mi) at 10 knots (19 km/h; 12 mph) surfaced 340 nmi (630 km; 390 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth	280 m (920 ft)
Complement	57–60 crewmen
Sensors and processing systems	Type F432 D2 Radar Transmitter FuMB Ant 3 Bali Radar Detector
Armament	6 × bow torpedo tubes 23 × 53.3 cm (21 in) torpedoes or 17 × torpedoes and 12 × TMC mines 4 × 2 cm (0.8 in) AA guns or 4 × 3.7 cm (1.5 in) AA guns
Service record
Part of:	4th U-boat Flotilla 28 February – 3 May 1945
Commanders:	Oblt.z.S. Heinrich Sach[1] 28 February – 3 May 1945
Operations:	None
Victories:	None

German submarine U-3031 was a Type XXI U-boat (one of the "Elektroboote") of Nazi Germany's Kriegsmarine, built for service in World War II. She was ordered on 6 November 1943, and was laid down on 30 October 1944 at AG Weser, Bremen, as yard number 1190. She was launched on 6 January 1945, and commissioned under the command of Oberleutnant zur See Heinrich Sach on 28 February 1945.^[2]

Design

Like all Type XXI U-boats, U-3031 had a displacement of 1,621 tonnes (1,595 long tons) when at the surface and 1,819 tonnes (1,790 long tons) while submerged. She had a total length of 76.70 m (251 ft 8 in) (o/a), a beam of 8 m (26 ft 3 in), and a draught of 6.32 m (20 ft 9 in).^[3] The submarine was powered by two MAN SE supercharged six-cylinder M6V40/46KBB diesel engines each providing 4,000 metric horsepower (2,900 kilowatts; 3,900 shaft horsepower), two Siemens-Schuckert GU365/30 double-acting electric motors each providing 5,000 PS (3,700 kW; 4,900 shp), and two Siemens-Schuckert silent running GV232/28 electric motors each providing 226 PS (166 kW; 223 shp).^[3]

The submarine had a maximum surface speed of 15.6 knots (28.9 km/h; 18.0 mph) and a submerged speed of 17.2 knots (31.9 km/h; 19.8 mph). When running on silent motors the boat could operate at a speed of 6.1 knots (11.3 km/h; 7.0 mph). When submerged, the boat could operate at 5 knots (9.3 km/h; 5.8 mph) for 340 nautical miles (630 km; 390 mi); when surfaced, she could travel 15,500 nautical miles (28,700 km; 17,800 mi) at 10 knots (19 km/h; 12 mph).^[3] U-3031 was fitted with six 53.3 cm (21.0 in) torpedo tubes in the bow and four 2 cm (0.79 in) C/30 anti-aircraft guns. She could carry twenty-three torpedoes or seventeen torpedoes and twelve mines. The complement was five officers and fifty-two men.^[3]

Fate

U-3031 was scuttled on 3 May 1945, at Kiel, as part of Operation Regenbogen. The wreck was later raised and broken up.^[2]