|Ordered:||6 November 1943|
|Builder:||Blohm & Voss, Hamburg|
|Laid down:||2 May 1944|
|Launched:||29 June 1944|
|Commissioned:||1 August 1944|
|Fate:||Scuttled on 4 May 1945|
|Class and type:||Type XXI submarine|
|Length:||76.70 m (251 ft 8 in) (o/a)|
|Beam:||8 m (26 ft 3 in)|
|Height:||11.30 m (37 ft 1 in)|
|Draught:||6.32 m (20 ft 9 in)|
|Test depth:||240 m (790 ft)|
|Complement:||5 officers, 52 enlisted|
|Sensors and |
German submarine U-2503 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 2 May 1944 at the Blohm & Voss, Hamburg, as yard number 2503. She was launched on 29 June 1944, and commissioned under the command of Oberleutnant zur See Raimund Tiesler, on 1 August 1944 .
Like all Type XXI U-boats, U-2503 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 length of 8 m (26 ft 3 in), and a draught length of 6.32 m (20 ft 9 in). 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).
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). U-2503 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.
On 3 May 1945, while on her way to Norway, U-2503 was in the Great Belt, near the Ömo Light Tower, when she was caught and attacked on the surface by Royal Air Force (RAF) Bristol Beaufighters of 236 Squadron and 254 Squadron, part of the Banff Strike Wing. U-2503 was struck in the area of the conning tower by at least one rocket, which caused severe damage and killed several crewmen and Kptlt. Karl-Jürg Wächter. U-2503, burning badly, was beached off of Omø, with 13 dead and an unknown number of survivors. The remaining crew landed ashore and scuttled the boat with explosives the next day.
U-2503's location when scuttled, Coordinates: .
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- Helgason, Guðmundur. "Richard Becker". Uboat.net. Retrieved 20 April 2016.
- Helgason, Guðmundur. "Karl-Jürg Wächter". Uboat.net. Retrieved 20 April 2016.
- Helgason, Guðmundur. "U-2503". German U-boats of WWII - uboat.net. Retrieved 20 April 2016.
- Gröner 1991, p. 85.
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- Busch, Rainer; Röll, Hans-Joachim (1999). Deutsche U-Boot-Verluste von September 1939 bis Mai 1945 [German U-boat losses from September 1939 to May 1945]. Der U-Boot-Krieg (in German). IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2.
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- Helgason, Guðmundur. "The Type XXI boat U-2503". German U-boats of WWII - uboat.net. Retrieved 20 April 2016.