German submarine U - 103 ( 1940 ) German submarine " U - 103 " was a Type IXB U - boat of the German " Kriegsmarine " that operated during World War II . She was one of the most successful boats in the entire war , sinking over 237 , 000 tons of Allied shipping in 11 patrols , in a career lasting more than four years . " U - 103 " was laid down on 6 September 1939 at AG Weser in Bremen as ' werk ' 966 . She was launched on 12 April 1940 and commissioned on 5 July under the command of " Korvettenkapitän " Victor Schütze . After her warm - up , ( designed to give her an opportunity to train and repair minor faults ) , she was deployed into the Atlantic Ocean in September , 1940 and saw overwhelming success , sinking 45 ships and damaging three other vessels . Operational career . 1st patrol . The boat entered the Atlantic via the ' gap ' between the Faroe and Shetland Islands . Her first victory was sinking the " Nina Borthen " in mid - ocean on 6 October . After being hit by a torpedo , the ship developed a list , which the crew corrected . The ship was hit by two more projectiles , which also caused a list . Another torpedo hit broke the vessel in two and she sank . There were no survivors . A steady stream of victories followed ; the " Zanes Gounaris " on 9 October , the " Graigwen " ( damaged ) also on the 9th , as was the " Delphin " , although she did not sink until the next day . The " Nora " went down on 13 October ; the " Thistlegarth " was the last victim - sinking west northwest of Rockall on 15 October . " U - 103 " docked at her new base - Lorient on the French Atlantic coast , on 19 October . 2nd patrol . " U - 103 " s second foray commenced with her being unsuccessfully attacked by the northwest of Ireland on 11 November 1940 . She then added to her score : the " Daydawn " on the 21st , the " Victoria " on the same day ; the " Glenmoor " on the 27th , the " Mount Athos " on the 28th and the " St . Elwyn " , also on the 28th . There was a slight pause before the attacks continued : the on 8 December and the " Empire Jaguar " the next day . The submarine returned to Lorient on 19 December . 3rd patrol . The list of sunk and damaged ships grew . The " Arthur F . Corwin " was damaged by " U - 103 " 13 February 1941 and sunk by later that same day . " U - 96 " went on to sink " Edwy R . Brown " ( 17 October ) , the " Seaforth " ( 18th ) and the " Benjamin Franklin " ( 19th ) . 4th patrol . A change of operational area saw " U - 103 " conduct her fourth sortie off the coast of West Africa . This patrol was also notable , because at 103 days , it was her longest . She sank the " Polyana " southwest of the Cape Verde Islands on 24 April 1941 . The ship went down in one minute , there were no survivors . The tally increased : the " Samsø " , the " Wray Castle " , the " Surat " and the " Dunkwa " were all sent to the bottom in the first week of May . When the " Dunkwa " met her end , it was noticed that there were 39 survivors in one lifeboat ; the U - boat - men righted another and provided water . " U - 103 " sank another eight ships in the vicinity of the ' dark continent ' before returning to Lorient on 12 July . 5th patrol . Patrol number five was relatively modest in terms of ships sunk . ' Only ' two vessels went under ; ( the " Niceto de Larrinaga " and the " Edward Blyden " ) , west of the Canary Islands on 22 September 1941 . 6th patrol . The boat ' s sixth patrol centred around the eastern US coast . She sank the " W . L . Stead " about off the Delaware river on 2 February 1942 . The torpedo hit set the ship on fire but wave action soon extinguished it . Using her deck gun , " U - 103 " fired 83 rounds , scoring 17 hits and reigniting the fire . She fired a further two torpedoes , the second missed , but the third caused the tanker ' s cargo to explode , sending flames into the air . " U - 103 " also sank the " San Gil " on 4 February , the " India Arrow " on the 5th and the " China Arrow " on the same date . 7th patrol . Her seventh patrol began with her departure from Lorient on 15 April 1942 . She sank the " Stanbank " northeast of Bermuda on 5 May . Moving into the Caribbean and the Gulf of Mexico , she caused more mayhem amongst the unprotected merchant ships in May . In all , she destroyed nine vessels on this voyage . " U - 103 " returned to Lorient on 22 June . 8th patrol . Two more ships went to watery graves - the " Tasmania " north of Madeira on 31 October 1942 and the " Henry Stanley " in mid - Atlantic northwest of the Azores on 6 December . The " Henry Stanley " s master was taken prisoner and was eventually sent to the POW camp for mechant seamen at Milag Nord . " U - 103 " also damaged the " Horata " north of the Azores on 13 December . 9th and 10th patrols . The boat experienced something that was relatively novel on her ninth sally - she sank no ships . Despite scouring the Atlantic off Spain as far west as the Azores and as far south as Morocco , she came across no convoys . Having departed Lorient on 7 February 1943 , she returned there on 26 March . " U - 103 " was attacked by a Leigh Light equipped Vickers Wellington of No . 172 Squadron RAF on 27 April , during her tenth patrol . The aircraft had found the U - boat with its radar ; six depth charges were dropped , but no damage inflicted . The boat was also attacked by a Whitley bomber of No . 10 OTU ( Operational Training Unit ) on 22 May . A hit from the boat ' s AA fire prevented the aircraft from dropping its depth charges . Plane and submarine both returned safely to their bases . 11th patrol . " U - 103 " s last operational patrol was officially divided into two parts ; the first of which saw her arrive in Brest in France only two days after her departure from ' Lorient . She then returned to the west African coast but could not repeat her earlier success . She sailed to Bergen in Norway via a reverse in the course of her first patrol and arrived at the Nordic port on 1 January 1944 . Fate . The boat moved from Bergen on 3 January 1944 and arrived in Kiel on the 7th . In March " U - 103 " was taken out of service and used as a " Schulboot " ( training boat ) . She went from Gotenhafen to Hamburg in January 1945 and in April from Hamburg back to Kiel . On 15 April 1945 she was sunk by Canadian bombers ; one man died and there were an unknown number of survivors .