German submarine U - 373 German submarine " U - 373 " was a Type VIIC U - boat of the Nazi German " Kriegsmarine " during World War II . She carried out thirteen patrols before being sunk by a British aircraft in June 1944 in the Bay of Biscay . * She was a member of 16 wolfpack s . She sank three ships . Service history . The submarine was laid down on 8 December 1939 at the Friedrich Krupp Germaniawerft at Kiel as ' Werk " 3 , launched on 5 April 1941 and commissioned on 22 May under the command of " Kapitänleutnant " Paul - Karl Loser . 1st patrol . The boat ' s first patrol was preceded by short trips between Kiel in Germany and Horten and Trondheim in Norway in July and August 1941 . Her first patrol proper commenced with her departure from Trondheim on 4 September . Negotiation of the ' gap ' separating Iceland and the Faroe Islands was followed by sweeps southeast of Greenland . The submarine then docked at Brest in occupied France on 2 October . 2nd - 5th patrols . " U - 373 " s initial patrols were fairly routine . All that changed on the second part of her fourth sortie when she sank the " Mount Lycabettus " off the eastern United States / Canadian coast on 17 March 1942 . On the 22nd , she sank the " Thursobank " east of Chesapeake Bay . The surviving Chinese crewmen from this ship were arrested for mutiny immediately after landing . It was alleged that they had denied the British officers a share of the food and warm clothing . She then sank the " John R . Williams " on 26 June 1942 with a mine laid on the 11th off Cape May . 6th , 7th and 8th patrols . " U - 373 " was unsuccessfully attacked by HNoMS " Acanthus " in mid - Atlantic on 25 August 1942 . The Norwegian corvette dropped five depth charge s , but the U - boat was not damaged . The boat ' s seventh foray was uneventful , but on her eighth she was bombed by a B - 24 Liberator of the USAAF on 2 March 1943 . Damage was moderate ; after repairs , " U - 373 " continued with her patrol . 9th patrol . On 24 July 1943 , the submarine was attacked west of Madeira by Avenger and Wildcat aircraft from the escort carrier USS " Santee " . Two men were killed , another seven were wounded . The boat was damaged by a FIDO homing torpedo , but was able to carry - on with her patrol . 10th and 11th patrols . During the third part of a three - part patrol on 10 November 1943 , a lookout broke his arm while the submarine fought bad weather . " U - 373 " had a lucky escape when she was attacked by a British Vickers Wellington of No . 612 Squadron RAF on 3 January 1944 in the Bay of Biscay . A second aircraft , a Liberator of 224 Squadron joined in . On tying up in Brest , two unexploded depth charges were discovered lodged in the conning tower . The boat was compelled to put to sea once more to jettison her unwanted extra ' cargo ' in another hazardous operation . 12th and 13th patrols and loss . The boat left Brest for the last time on 7 June 1944 . The following day , she was sunk by a British Liberator of 224 Squadron in the Bay of Biscay . * The same aircraft sank " U - 441 " 20 minutes later . Four men died in " U - 373 " ; there were 47 survivors . Summary of raiding history . * The source ' s map shows the attack location to be in the Bay of Biscay . ( west ) However , the text mentions Cadiz , which is many miles to the south .