German submarine U-633

German submarine U-633 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 22 September 1941 by Blohm & Voss, Hamburg as yard number 609, launched on 10 June 1942 and commissioned on 30 July 1942 under Oberleutnant zur See Bernhard Müller.

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-633 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 BBC GG UB 720/8 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-633 was fitted with five torpedo tubes, fourteen torpedoes, one SK C/35 naval gun, 220 rounds, and one twin C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.

The boat's career began with training at 5th U-boat Flotilla on 30 July 1942, followed by active service on 1 March 1943 as part of the 9th Flotilla for the remainder of her short service. In one patrol she sank one merchant ship, for a total of.

U-633 was sunk on 8 March 1943 in the North Atlantic south-west of Iceland, in position, by depth charges from the US Coast Guard cutter USCGC Spencer. 43 dead.

U-633 took part in two wolfpacks, namely: