German submarine U-621

Summary

German submarine U-621 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 1 July 1941 by Blohm & Voss in Hamburg as yard number 597, launched on 19 March 1942 and commissioned on 7 May 1942 under Kapitänleutnant Horst Schünemann.

History
Nazi Germany
NameU-621
Ordered15 August 1940
BuilderBlohm & Voss, Hamburg
Yard number597
Laid down1 July 1941
Launched19 March 1942
Commissioned7 May 1942
FateSunk on 18 August 1944 near La Rochelle at position 45°52′N 02°36′W / 45.867°N 2.600°W / 45.867; -2.600 by depth charges from Canadian destroyers Ottawa, Kootenay and Chaudiere.
General characteristics
Class and typeType VIIC submarine
Displacement
Length
Beam
  • 6.20 m (20 ft 4 in) o/a
  • 4.70 m (15 ft 5 in) pressure hull
Height9.60 m (31 ft 6 in)
Draught4.74 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
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)
Complement4 officers, 40–56 enlisted
Armament
Service record[1]
Part of:
Identification codes: M 02 082
Commanders:
Operations:
  • 10 patrols:
  • 1st patrol:
  • 29 September – 5 November 1942
  • 2nd patrol:
  • 5 December 1942 – 5 January 1943
  • 3rd patrol:
  • 1 February – 23 March 1943
  • 4th patrol:
  • 22 April – 3 June 1943
  • 5th patrol:
  • 22 August – 28 September 1943
  • 6th patrol:
  • 6 – 23 January 1944
  • 7th patrol:
  • 21 February – 19 April 1944
  • 8th patrol:
  • 6 – 23 June 1944
  • 9th patrol:
  • 15 July – 11 August 1944
  • 10th patrol:
  • 13 – 18 August 1944
Victories:
  • 4 merchant ships sunk
    (20,159 GRT)
  • 1 auxiliary warship sunk
    (2,938 GRT)
  • 1 merchant ship damaged
    (10,048 GRT)
  • 1 warship damaged
    (1,625 tons)

Design edit

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-621 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 Brown, Boveri & Cie 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-621 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 a 2 cm (0.79 in) C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.[2]

Service history edit

The boat's service began on 7 May 1942 for training as part of the 8th U-boat Flotilla. After training was completed she transferred to the 9th flotilla on 1 October 1942 for active service.

In ten patrols she sank four merchant ships for a total of 20,159 gross register tons (GRT), plus one auxiliary warship. She also damaged two more ships.

Wolfpacks edit

She took part in eleven wolfpacks, namely:

  • Panther (10 – 16 October 1942)
  • Puma (16 – 29 October 1942)
  • Raufbold (11 – 18 December 1942)
  • Hartherz (3 – 7 February 1943)
  • Ritter (11 – 26 February 1943)
  • Burggraf (4 – 5 March 1942)
  • Raubgraf (7 – 15 March 1943)
  • Amsel 1 (3 – 6 May 1943)
  • Elbe (7 – 10 May 1943)
  • Elbe 2 (10 – 14 May 1943)
  • Mosel (19 – 24 May 1943)

Fate edit

She was sunk by depth charges dropped by three Royal Canadian Navy destroyers, HMCS Ottawa, HMCS Kootenay and HMCS Chaudiere on 18 August 1944 near La Rochelle at position 45°52′N 02°36′W / 45.867°N 2.600°W / 45.867; -2.600.

Summary of raiding history edit

Date Ship Name Nationality Tonnage[Note 1] Fate[3]
23 October 1942 Empire Turnstone   United Kingdom 6,113 Sunk
18 December 1942 Oropos   Greece 4,474 Sunk
20 December 1942 Otina   United Kingdom 6,217 Sunk
11 March 1943 Baron Kinnaird   United Kingdom 3,355 Sunk
15 June 1944 USS LST-133   United States Navy 1,625 Damaged
29 July 1944 HMS Prince Leopold   Royal Navy 2,938 Sunk
30 July 1944 Ascanius   United Kingdom 10,048 Damaged

References edit

Notes edit

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

Citations edit

  1. ^ Helgason, Guðmundur. "The Type VIIC boat U-621". German U-boats of WWII - uboat.net. Retrieved 3 May 2014.
  2. ^ a b c d Gröner 1991, pp. 43–46.
  3. ^ Helgason, Guðmundur. "Ships hit by U-621". German U-boats of WWII - uboat.net. Retrieved 3 May 2014.

Bibliography edit

  • 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.
  • Edwards, Bernard (1996). Dönitz and the Wolf Packs – The U-Boats at War. London, UK: Cassell Military Classics. p. 161. ISBN 0-304-35203-9.
  • 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.

External links edit

  • Helgason, Guðmundur. "The Type VIIC boat U-621". German U-boats of WWII - uboat.net. Retrieved 29 December 2014.