German submarine U-642

German submarine U-642 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 19 November 1941 by Blohm & Voss, Hamburg as yard number 618, launched on 6 August 1942 and commissioned on 1 October 1942 under Kapitänleutnant Herbert Brünning.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-642 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 Brown, Boveri & Cie GG UB 720/8 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-642 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 twin 2 cm C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.

Service history
The boat's career began with training at 5th U-boat Flotilla on 1 October 1942, followed by active service on 1 March 1943 as part of the 6th Flotilla. She transferred for operations in the Mediterranean on 1 December 1943 to serve with 29th Flotilla for the remainder of her service.

In 4 patrols she sank 1 merchant ship, for a total of.

Wolfpacks
U-642 took part in nine wolfpacks, namely:
 * Neuland (4 – 6 March 1943)
 * Ostmark (6 – 11 March 1943)
 * Stürmer (11 – 20 March 1943)
 * Seewolf (21 – 30 March 1943)
 * Oder (17 – 19 May 1943)
 * Mosel (19 – 24 May 1943)
 * Trutz (1 – 16 June 1943)
 * Trutz 1 (16 – 29 June 1943)
 * Geier 3 (30 June – 15 July 1943)

Fate
U-642 was sunk on 5 July 1944 in the Mediterranean at Military port of Toulon in position 43.11667°N, 5.91667°W, by a US air raid.