German submarine U-711

Summary

German submarine U-711 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II.

History
Nazi Germany
NameU-711
Ordered7 December 1940
BuilderH. C. Stülcken Sohn, Hamburg
Yard number777
Laid down31 July 1941
Launched25 June 1942
Commissioned26 September 1942
FateSunk on 4 May 1945 at 68°48′N 16°38′E / 68.800°N 16.633°E / 68.800; 16.633
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
Range8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph)
Test depth
  • 230 m (750 ft)
  • Crush depth: 250–295 m (820–968 ft)
Complement44–60 officers & ratings
Armament
Service record
Part of:
Identification codes: M 50 659
Commanders:
Operations:
  • 12 patrols:
  • 1st patrol:
  • a. 25 March – 30 April 1943
  • b. 12 – 14 May 1943
  • 2nd patrol:
  • 25 May – 18 June 1943
  • 3rd patrol:
  • a. 22 July – 30 September 1943
  • b. 2 – 5 October 1943
  • c. 15 – 17 December 1943
  • d. 18 – 19 December 1943
  • e. 20 – 23 December 1943
  • f. 19 – 21 March 1944
  • 4th patrol:
  • 22 March – 6 April 1944
  • 5th patrol:
  • 11 – 15 April 1944
  • 6th patrol:
  • 24 April – 5 May 1944
  • 7th patrol:
  • a. 30 May – 8 July 1944
  • b. 29 – 30 July 1944
  • 8th patrol:
  • a. 2 – 19 August 1944
  • b. 22 – 26 August 1944
  • c. 27 – 28 August 1944
  • d. 3 – 5 September 1944
  • 9th patrol:
  • a. 7 September – 4 October 1944
  • b. 6 – 8 October 1944
  • c. 23 – 26 January 1945
  • 10th patrol:
  • 9 – 24 February 1945
  • 11th patrol:
  • 14 – 31 March 1945
  • 12th patrol:
  • 15 April – 2 May 1945
Victories:
  • 1 merchant ship sunk
    (10 GRT)
  • 1 warship sunk
    (925 tons)
  • 1 auxiliary warship damaged
    (20 GRT)

Ordered 7 December 1940, laid down, 31 July 1941 and launched 25 June 1942. She was commanded by Oberleutnant zur See Hans-Günther Lange (who was awarded the Knights Cross).

Design edit

German Type VIIC submarines had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged.[1] U-711 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 AEG GU 460/8–27 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).[1]

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).[1] 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-711 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, removed in the summer of 1944, when she was fitted with the schnorkeland and two, twin 2 cm (0.79 in) C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.[1]

Service history edit

During her active service career, U-711 sank 2 ships and damaged a third.

U-711 attacked and sank the British corvette HMS Bluebell on 17 February 1945 with an acoustic homing torpedo, which caused her depth charges to explode. Bluebell sank in less than 30 seconds and from her crew of 86 there was only one survivor.[2]

 
U-711 is just visible behind water columns, smoke and the depot ship Black Watch

Fate edit

On 4 May 1945, U-711 was sunk by aircraft of the Fleet Air Arm during Operation Judgement, an attack on the depot ships MS Black Watch and Senja anchored at Kilbotn, south of Harstad, Norway. This was the last air-raid of the war in Europe.

Avenger and Wildcat aircraft, from FAA Squadrons 846, 853 and 882, operating from the British escort carriers HMS Trumpeter, HMS Queen and HMS Searcher sank the Black Watch with 7 direct hits and 4 near misses. U-711, was moored alongside and was damaged but managed to sail away. The U-Boat had a harbour crew of eight on board, including the captain, who all survived although forty of her crew who were berthed on the depot ship were killed. The submarine later sank.

A few hours earlier Lange had received the signal from Germany ordering all U-boats to cease attacks on allied shipping.[3]

Wolfpacks edit

U-711 took part in nine wolfpacks, namely:

  • Wiking (1 August – 20 September 1943)
  • Blitz (24 March – 5 April 1944)
  • Keil (11 – 14 April 1944)
  • Donner & Keil (24 April – 3 May 1944)
  • Grimm (31 May – 6 June 1944)
  • Trutz (8 June – 7 July 1944)
  • Greif (3 – 18 August 1944)
  • Rasmus (9 – 13 February 1945)
  • Hagen (15 – 21 March 1945)

Summary of raiding history edit

Date Ship Name Nationality Tonnage[Note 1] Fate[4]
13 April 1944 Solvoll   Norway 10 Sunk
17 February 1945 HMS Bluebell   Royal Navy 925 Sunk
22 March 1945 VPS-5   Soviet Navy 20 Damaged

Dive site edit

As no-one was killed during her sinking, U-711's location is not classed as a war grave and is a well-documented dive-site, lying at approximately 50 meters depth and only having minor damage.[5]

References edit

Notes edit

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

Citations edit

  1. ^ a b c d Gröner 1991, pp. 43–46.
  2. ^ Naval History HMS Bluebell.
  3. ^ Harald Isachsen (2009), Operation Judgement: Angrepet på <<Black Watch>>, Kilbotn 4 Mai 1945, ISBN 978-82-998024-2-0
  4. ^ Helgason, Guðmundur. "Ships hit by U-711". German U-boats of WWII - uboat.net. Retrieved 10 February 2014.
  5. ^ Wreck site - U-711

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). 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). 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-711". German U-boats of WWII - uboat.net. Retrieved 29 December 2014.
  • Hofmann, Markus. "U 711". Deutsche U-Boote 1935-1945 - u-boot-archiv.de (in German). Retrieved 29 December 2014.