German submarine U-637

German submarine U-637 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 17 October 1941 by Blohm & Voss, Hamburg as yard number 613, launched on 7 July 1942 and commissioned on 27 August 1942 under Kapitänleutnant Max Bernd Dieterich.

History
Nazi Germany
Name	U-637
Ordered	20 January 1941
Builder	Blohm & Voss, Hamburg
Yard number	613
Laid down	17 October 1941
Launched	7 July 1942
Commissioned	27 August 1942
Fate	Surrendered on 9 May 1945 at Stavanger. Later sunk as part of Operation Deadlight on 21 December 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
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	230 m (750 ft) Crush depth: 250–295 m (820–968 ft)
Complement	4 officers, 40–56 enlisted
Armament	5 × 53.3 cm (21 in) torpedo tubes (4 bow, 1 stern) 14 × torpedoes or 26 TMA mines 1 × 8.8 cm (3.46 in) deck gun (220 rounds) 1 × twin 2 cm (0.79 in) C/30 anti-aircraft gun
Service record[1]
Part of:	5th U-boat Flotilla 27 August 1942 – 31 May 1944 1st U-boat Flotilla 1 June – 5 July 1944 8th U-boat Flotilla 6 July 1944 – 1 January 1945 5th U-boat Flotilla 1 January – 8 May 1945
Identification codes:	M 51 550
Commanders:	Kptlt. Max Bernd Dieterich 27 August 1942 – 22 February 1943 Kptlt. Günther Zedelius 23 February 1943 – 20 July 1944 Oblt.z.S. Fritz Fabricius 21 July – 30 September 1944 Kptlt. Wolfgang Riekeberg 1 October 1944 – 26 April 1945 Oblt.z.S. Walter Ehrhardt January 1945 Oblt.z.S. Klaus Weber 27 April – 9 May 1945
Operations:	3 patrols: 1st patrol: 25 November 1944 – 13 January 1945 2nd patrol: 5 – 13 April 1945 3rd patrol: 23 – 28 April 1945
Victories:	1 warship sunk (39 tons)

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-637 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged.^[2] 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 BBC GG UB 720/8 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).^[2]

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).^[2] 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-637 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm (3.46 in) SK C/35 naval gun, 220 rounds, and one twin 2 cm (0.79 in) C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.^[2]

Service history

The boat's career began with training at 5th U-boat Flotilla on 27 August 1942, followed by active service on 1 June 1944 as part of the 1st Flotilla.

In three patrols she sank one warship, for a total of 39 tons.

Fate

U-637 surrendered on 9 May 1945 at Stavanger and later sunk as part of Operation Deadlight on 21 December 1945 at position 55°35′N 07°46′W.

Summary of raiding history

Date	Ship Name	Nationality	Tonnage[Note 1]	Fate[3]
24 December 1944	BMO-594	Soviet Navy	39	Sunk

References

Notes

1. Merchant ship tonnages are in gross register tons. Military vessels are listed by tons displacement.

Citations

1. Helgason, Guðmundur. "The Type VIIC boat U-637". German U-boats of WWII - uboat.net. Retrieved 12 November 2014.
2. Gröner 1991, pp. 43–46.
3. Helgason, Guðmundur. "Ships hit by U-637". German U-boats of WWII - uboat.net. Retrieved 12 November 2014.

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). Der U-Boot-Krieg, 1939-1945: Deutsche U-Boot-Verluste von September 1939 bis Mai 1945 [German U-boat losses from September 1939 to May 1945] (in German). Vol. IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2.
• Gröner, Eric; Jung, Dieter; Maass, Martin (1991). German Warships 1815-1945: U-boats and Mine Warfare Vessels. Vol. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.
• Sharpe, Peter (1998). U-Boat Fact File. Great Britain: Midland Publishing. ISBN 1-85780-072-9.

External links

• Helgason, Guðmundur. "The Type VIIC boat U-637". German U-boats of WWII - uboat.net. Retrieved 29 December 2014.