German submarine U-665

German submarine U-665 was a [German German Type VIIC submarine|Type VIIC submarine|Type VIIC] U-boat built for Nazi Germany's Kriegsmarine for service during World War II.
She was laid down on 10 June 1941 by Deutsche Werft, Hamburg as yard number 814, launched on 9 June 1942 and commissioned on 22 July 1942 under Leutnant zur See Hans-Jürgen Haupt.

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-665 had a displacement of when at the surface and while submerged. She had a total length of, a pressure hull length of, a beam of, a height of, and a draught of. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of for use while surfaced, two Siemens-Schuckert GU 343/38–8 double-acting electric motors producing a total of for use while submerged. She had two shafts and two propellers. The boat was capable of operating at depths of up to.
The submarine had a maximum surface speed of and a maximum submerged speed of. When submerged, the boat could operate for at ; when surfaced, she could travel at. U-665 was fitted with five torpedo tubes, fourteen torpedoes, one SK C/35 naval gun, 220 rounds, and two twin C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.

The boat's career began with training at 5th U-boat Flotilla on 22 July 1942, followed by active service on 1 February 1943 as part of the 1st Flotilla for the remainder of her short service. In her sole patrol she sank one merchant ship, for a total of.

U-665 took part in three wolfpacks, namely:

U-665 has been missing since 22 March 1943 in the Bay of Biscay, west of La Pallice.

U-665 was thought to have been sunk on 22 March 1943 in the Bay of Biscay west of Nantes at, by depth charges from Vickers Wellington aircraft of No. 172 Squadron RAF. This attack was actually against U-448, inflicting no damage.
U-665 was also thought to have been sunk on 22 March 1943 in the North Atlantic at, by depth charges from an Armstrong Whitworth Whitley VII of No. 10 Operational Training Unit RAF, for the loss of all hands.