German submarine U-706, a type VIIC U-boat, was laid down on 22 November 1940. She was launched on 24 November 1941 and commissioned on 16 March 1942.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-706 had a displacement of 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Garbe, Lahmeyer & Co. RP 137/c double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on 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-706 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and a 2sp=usNaNsp=us C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
U-706 was commanded by Korvettenkapitän Alexander von Zitzewitz. She was attached to the 5th Flotilla from 16 March until 30 September 1942. On 1 October 1942, she was transferred to the 3rd Flotilla and made five patrols during the war, sinking three ships with a total tonnage of . On 2 August 1943, while in Bay of Biscay, she was disabled by depth charges from a Canadian Hampden aircraft, then finished off by a US Liberator aircraft from A/S Sqdn. 4. She sank at position 46.25°N -35°W.
U-706 took part in ten wolfpacks, namely:
| Date | Ship Name | Nationality | Tonnage (GRT) | Fate[1] | |
|---|---|---|---|---|---|
| 12 October 1942 | Stornest |  United Kingdom | 4,265 | Sunk | |
| 5 April 1943 | British Ardour | United Kingdom | 7,124 | Sunk | |
| 12 April 1943 | Fresno City | United Kingdom | 7,261 | Sunk |