German submarine U-355

German submarine U-355 was a Type VIIC U-boat of the Nazi German Kriegsmarine during World War II. The submarine was laid down in May 1940 at the Flensburger Schiffbau-Gesellschaft yard at Flensburg, launched in July 1941, and commissioned in October under the command of Kapitänleutnant Günter La Baume. After training with the 5th U-boat Flotilla, U-355 was transferred to the 11th U-boat Flotilla, based at Bergen in Norway, for front-line service from 1 July 1942. The boat went missing on 1 April 1944 while on patrol, and was never heard from again.

Construction and Design
U-355 was ordered by the Kriegsmarine on 26 October 1939. She was laid down about six months later at the Flensburger Schiffbau-Gesellschaft yard at Flensburg, on 4 May 1940. Just over a year and a month later, U-355 was launched on 5 July 1941. She was formally commissioned later that year on 29 October 1941. U-355 carried 5 × 533 mm torpedo tubes (four located in the bow, one in the stern) and had one C35 88mm/L45 deck gun with 220 rounds. She could also carry 14 G7e torpedoes or 26 TMA mines and had a crew of 44-52 men.

Patrols
U-355 sailed from Kiel on 1 June 1942, arriving at Skjomenfjord, near Narvik, six days later. She sailed on her first combat patrol ten days later, on 16 June, and headed out into the Barents Sea.

There, on 7 July 1942, she sank the 5,082 ton British merchant ship SS Hartlebury, dispersed from Convoy PQ 17, en route to Arkhangelsk, carrying six vehicles, 36 tanks, seven aircraft and 2,409 tons of military stores. The ship, hit by three torpedoes, sank within 10 minutes around 17 miles west of Novaya Zemlya. Of the crew, 29 men, seven gunners, and two naval signalmen were killed. The master and 12 men landed at Pomorski Bay, Novaya Zemlya. Another seven survivors took shelter on the American merchant ship SS Winston-Salem, (also of PQ 17), which had run aground and been abandoned on North Gusini Shoal, Novaya Zemlya, and were later rescued by a Soviet survey ship. The U-boat returned to Narvik on 12 July after 27 days at sea.

This was U-355's only success despite sailing on another eight patrols operating against the Arctic convoys between July 1942 and April 1944, totaling 187 days at sea.

Loss
On 1 April 1944, during her ninth patrol, U-355 reported from approximate position 73.05°N, 13.16667°W while in pursuit of Convoy JW 58. She was never heard from again, and was listed as missing, together with 52 hands on board, on 4 April 1944. Post-war analysis led the Admiralty to credit her destruction to HMS Beagle (H30) and aircraft from HMS Tracker (D24). Other sources dispute this, claiming U-355 was lost due to an unknown cause.