German submarine U-170

German submarine U-170 was a Type IXC/40 U-boat of the Nazi German Kriegsmarine built for service during World War II. Her keel was laid down on 21 May 1941 by the Deutsche Schiff- und Maschinenbau AG in Bremen as 'werk' 709. She was launched on 6 June 1942 and commissioned on 19 January 1943 with Kapitänleutnant Günther Pfeffer in command.

The U-boat's service began with training as part of the 4th U-boat Flotilla. She then moved to the 10th flotilla on 1 June 1943 for operations. She was re-assigned to the 33rd flotilla on 1 November 1944.

1st patrol
U-170's first patrol began with her departure from Kiel on 27 May 1943. Her route took her the long way around the British Isles to the Atlantic Ocean west of the Azores. She had passed through the 'gap' between Iceland and the Faroe Islands. She arrived at Lorient in occupied France on 9 July.

2nd patrol
Her second sortie was to the Brazilian coast. Here she sank the Campos (4,663 tons) on 23 October 1943, 5 mi south of Alcatazes Island.

3rd patrol
The boat's third foray was to the US east coast. She departed Lorient on 9 February 1944 and returned to the same port on 27 May.

4th patrol
Her last patrol was to the waters off west Africa. On the return voyage to Germany, she was attacked by unidentified destroyers west of southern Ireland on 30 October 1944 and badly damaged. She also reported a damaged Schnorchel (underwater breathing device), on 5 November and docked in Norway for repairs. She arrived at Flensburg on 4 December.

Fate
She was sunk on 30 November 1945 as part of Operation Deadlight. She had surrendered in Horten, Norway on 9 May 1945, and was transferred to Loch Ryan in Scotland.