German submarine U-904

German submarine U-904 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II.

U-570 Type VIIC submarine that was captured by the British in 1941. This U-boat is almost identical to U-904.
History
Nazi Germany
Name	U-904
Ordered	16 July 1942
Builder	Flender Werke AG, Lübeck
Yard number	330
Laid down	10 September 1942
Launched	7 August 1943
Commissioned	25 September 1943
Fate	Scuttled on 4 May 1945
General characteristics
Class and type	Type VIIC submarine
Displacement	769 tonnes (757 long tons) surfaced 871 t (857 long tons) submerged
Length	67.10 m (220 ft 2 in) o/a 50.50 m (165 ft 8 in) pressure hull
Beam	6.20 m (20 ft 4 in) o/a 4.70 m (15 ft 5 in) pressure hull
Height	9.60 m (31 ft 6 in)
Draught	4.74 m (15 ft 7 in)
Installed power	2,800–3,200 PS (2,100–2,400 kW; 2,800–3,200 bhp) (diesels) 750 PS (550 kW; 740 shp) (electric)
Propulsion	2 shafts 2 × diesel engines 2 × electric motors
Speed	17.7 knots (32.8 km/h; 20.4 mph) surfaced 7.6 knots (14.1 km/h; 8.7 mph) submerged
Range	8,500 nmi (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph) surfaced 80 nmi (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth	220 m (720 ft) Crush depth: 250–295 m (820–968 ft)
Complement	4 officers, 44–52 enlisted
Armament	5 × 53.3 cm (21 in) torpedo tubes (four bow, one stern) 14 × torpedoes or 26 TMA mines 1 × 8.8 cm (3.46 in) deck gun (220 rounds) 1 × 3.7 cm (1.5 in) Flak M42 AA gun 2 × twin 2 cm (0.79 in) C/30 anti-aircraft guns
Service record
Part of:	23rd U-boat Flotilla 25 September 1943 – 28 February 1945 5th U-boat Flotilla 1 March – 4 May 1945
Identification codes:	M 52 703
Commanders:	Lt.z.S. / Oblt.z.S. Detlev Fritz 25 September – 30 November 1943 Oblt.z.S. Dieter Erdmann 1 December 1943 – 15 June 1944 Oblt.z.S. Günter Stührmann 16 June 1944 – 4 May 1945
Operations:	None
Victories:	None

She was ordered on 16 July 1942, and was laid down on 10 September 1942 at Flender Werke AG, Lübeck, as yard number 330. She was launched on 7 August 1943 and commissioned under the command of Leutnant zur See Detlev Fritz on 25 September 1943.

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-904 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged. She had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two SSW GU 343/38-8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. She had two shafts and two 1.23 m (4 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).

The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a maximum submerged speed of 7.6 knots (14.1 km/h; 8.7 mph). When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph). U-904 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes or 26 TMA mines, one 8.8 cm (3.46 in) SK C/35 naval gun, (220 rounds), one 3.7 cm (1.5 in) Flak M42 and two twin 2 cm (0.79 in) C/30 anti-aircraft guns. The boat had a complement of between 44 — 52 men.

Service history

On 4 May 1945, U-904 was scuttled at the U-boat base in Eckernförde.

Bibliography

• Busch, Rainer; Röll, Hans-Joachim (1999). German U-boat commanders of World War II : a biographical dictionary. Translated by Brooks, Geoffrey. London, Annapolis, Md: Greenhill Books, Naval Institute Press. ISBN 1-55750-186-6.
• 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). Vol. IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2.
• Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. Vol. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.

External links

• Helgason, Guðmundur. "The Type VIIC boat U-904". German U-boats of WWII - uboat.net.