German submarine U-71 (1940)

German submarine U-71 was a type VII C submarine of Nazi Germany's Kriegsmarine during the Second World War.

Ordered on 25 January 1939, her keel was laid down as yard number 618 on 21 December that year. She was launched on 31 October 1940 and commissioned on 14 December. She entered the 7th U-boat Flotilla as a training submarine (commissioning until 31 May 1941), then served as a front (operational) boat between 1 June 1941 and 31 May 1943. During that time she carried out ten war patrols, but had to return to port following damage after colliding with GS U-631 in the North Atlantic on 17 April 1943.

After that, she moved to the 24th U-boat Flotilla as a training submarine (1 June 1943 – 30 June 1944), then to the 22nd flotilla also as a training boat from 1 July 1944 until 27 February 1945. She was a member of 17 wolfpacks. She sank five ships and was scuttled on 2 May 1945 at Wilhelmshaven, six days before the German surrender.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-71 had a displacement of 769 t when at the surface and 871 t while submerged. She had a total length of 67.10 m, a pressure hull length of 50.50 m, a beam of 6.20 m, a height of 9.60 m, and a draught of 4.74 m. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2800 to 3200 PS for use while surfaced, two AEG GU 460/8–27 double-acting electric motors producing a total of 750 PS for use while submerged. She had two shafts and two 1.23 m propellers. The boat was capable of operating at depths of up to 230 m.

The submarine had a maximum surface speed of 17.7 kn and a maximum submerged speed of 7.6 kn. When submerged, the boat could operate for 80 nmi at 4 kn; when surfaced, she could travel 8500 nmi at 10 kn. U-71 was fitted with five 53.3 cm torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm SK C/35 naval gun, 220 rounds, and one 2 cm C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.

First, second, third and fourth patrols
U-71's early history was fairly typical of many boats in the U-Boot-Waffe (U-boat arm); she began her operational life in Kiel, but soon moved to St. Nazaire in France, where despite being nearer to the main hunting grounds of the Atlantic, failed to take advantage of her more advanced location. This was between August 1941 and January 1942.

Fifth patrol


Her luck and that of her commander, Kapitänleutnant Walter Flachenberg, changed on her fifth foray, sinking a total of of shipping in March and April 1942. She returned to France, but this time to La Pallice.

Sixth patrol
Flachenberg was unable to repeat his success on U-71's sixth and his last patrol, returning to St. Nazaire empty-handed.

Seventh, eighth and ninth patrols
Under a new skipper, Hardo Rodler von Roithberg, the boat could not reproduce the form of her fifth patrol, despite sortieing three times between July 1942 and February 1943.

Tenth patrol
By now the writing was on the wall for Germany's U-boats; U-71 was only one submarine that departed La Rochelle and after another unsuccessful voyage, steamed to Königsberg (on the Baltic coast), arriving in May 1943.

Wolfpacks
U-71 took part in 17 wolfpacks, namely:
 * Grönland (10 – 27 August 1941)
 * Bosemüller (28 August – 2 September 1941)
 * Seewolf (2 – 3 September 1941)
 * Breslau (2 – 29 October 1941)
 * Seeräuber (21 – 23 December 1941)
 * Seydlitz (27 December 1941 – 16 January 1942)
 * Endrass (12 – 16 June 1942)
 * Wolf (13 – 30 July 1942)
 * Pirat (31 July – 3 August 1942)
 * Steinbrinck (3 – 7 August 1942)
 * Panther (10 – 20 October 1942)
 * Veilchen (20 October – 7 November 1942)
 * Falke (28 December 1942 – 19 January 1943)
 * Landsknecht (19 – 28 January 1943)
 * Hartherz (3 – 7 February 1943)
 * Adler (7 – 13 April 1943)
 * Meise (13 – 17 April 1943)