German submarine U - 275 German submarine " U - 275 " was a Type VIIC U - boat of the Nazi German " Kriegsmarine " during World War II . The submarine was laid down on 18 January 1942 at the " Bremer - Vulkan - Vegesacker Werft " ( yard ) in Bremen as ' werk ' 40 . She was launched on 8 October 1942 and commissioned on 25 November under the command of " Oberleutnant " Helmut Bork . In nine patrols , she sank two ships of 6 , 024 GRT . She was a member of four wolf pack s . She was sunk by a mine in the English Channel in March 1945 . Service history . After training with the 8th U - boat Flotilla , the boat became operational on 1 June 1943 when she was transferred to the 3rd flotilla . " U - 275 " carried out a series of short voyages between Kiel in Germany and Bergen and Trondheim in Norway in August 1943 . 1st patrol . The boat ' s first patrol proper began when she departed Bergen on 24 September 1943 . She entered the Atlantic Ocean after negotiating the ' gap ' between Iceland and the Faroe Islands . She was unsuccessfully attacked by a Lockheed Hudson southwest of Iceland . She reached La Pallice in occupied France on 28 October . 2nd patrol . The boat ' s second foray was divided into a series of short bursts between La Pallice and Brest between November 1943 and April 1944 . It was during one of these sallies that she sank the USS " Leary " , an American destroyer , on 24 December 1943 . < br > Another moment of drama came when the submarine was obliged to return to base on 3 January with the captain suffering from appendicitis . 3rd and 4th patrols . Patrol number three was similarly short , starting and finishing in Brest on 20 and 23 May 1944 . Not long after D - Day ( 6 June 1944 ) on her fourth sortie , she was attacked by no less than 12 Hawker Typhoon strike attack aircraft of No . 263 Squadron RAF while leaving St . Peter Port , Guernsey on 14 June . No damage was caused to the submarine ; the escorting vessels were not so lucky . 5th patrol . While negotiating the relatively shallow waters of the English Channel , the submarine was discovered by an aircraft which vectored a hunter - killer group onto her . She then spent seven hours being chased before she shook off her pursuers . The situation had become so dire that the boat was chased every time she raised her periscope . She eventually reached comparative safety in Boulogne on 2 August 1944 . 6th patrol . It was decided to send " U - 275 " back to Norwegian waters . She sailed westward , the ' long ' way around the British Isles . She had almost reached Bergen on 18 September 1944 , when she was attacked by a total of eight De Haviland Mosquito s . Two were armed with the " Tse tse " 6 pounder cannon , four more were equipped with depth charge s , ( they were all from 248 Squadron ) , while the last two , from 235 Squadron , were there as escorts . The submarine grounded in water that was only about deep . She was strafed and bombed while half submerged . However , luck was on the U - boat ' s side ; one cannon jammed and two bombs failed to release . A coastal battery also fired on the British aircraft , causing them to leave the scene of the attack . The U - boat , having suffered some damage , then made her way to her destination . 7th and 8th patrols . These two patrols were relatively trouble - free , but the boat did return to the French Atlantic coast , docking at St . Nazaire on 10 February 1945 . 9th patrol and loss . Having departed St . Nazaire on 25 February 1945 , she headed for the English Channel once more . On 8 March she sank the " Lonaston " northwest of Fécamp . On the 10th she struck a mine off Beachy Head and sank . Forty - eight men died ; there were no survivors .