German submarine U-621


German submarine U-621 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 1 July 1941 by Blohm & Voss in Hamburg as yard number 597, launched on 19 March 1942 and commissioned on 7 May 1942 under Kapitänleutnant Horst Schünemann.

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-621 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 Brown, Boveri & Cie 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-621 was fitted with five torpedo tubes, fourteen torpedoes, one SK C/35 naval gun, 220 rounds, and a C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.

Service history

The boat's service began on 7 May 1942 for training as part of the 8th U-boat Flotilla. After training was completed she transferred to the 9th flotilla on 1 October 1942 for active service.
In ten patrols she sank four merchant ships for a total of, plus one auxiliary warship. She also damaged two more ships.

Wolfpacks

She took part in eleven wolfpacks, namely:
  • Panther
  • Puma
  • Raufbold
  • Hartherz
  • Ritter
  • Burggraf
  • Raubgraf
  • Amsel 1
  • Elbe
  • Elbe 2
  • Mosel

Fate

She was sunk by depth charges dropped by three Royal Canadian Navy destroyers,, and on 18 August 1944 near La Rochelle at position.