German submarine U - 73 ( 1940 ) German submarine " U - 73 " was a Type VIIB U - boat of the " Kriegsmarine " ( German Navy ) during World War II . She was laid down by Bremer Vulkan of Bremen - Vegesack , Germany as ' Werk ' 1 on 5 November 1939 , launched on 27 July 1940 and commissioned on 30 September of the same year under " Kapitänleutnant " ( " Kptlt . " ) Helmut Rosenbaum . " U - 73 " carried out 15 patrols between early 1941 and late 1943 , sinking eight ships and four warships . She also damaged a further three commercial vessels . She was a member of five wolfpack s . She was sunk by two US warships , and , off the North African coast on 16 December 1943 at . Service history . 1st patrol . " U - 73 " departed the Helgoland ( also known as Heligoland ) for her first patrol on 8 February 1941 . Her route took her the length of the North Sea , through the ' gap ' separating the Faroe and Shetland Islands , northwest toward Iceland , then south and west . She sank the " Waynegate " on 24 February 1941 south of Iceland . The boat arrived at Lorient , on the French Atlantic coast , on 2 March . 2nd patrol . " U - 73 " sank three ships on the same day , 3 April 1941 . They were : the " Alderpool " , the " Westpool " and the " British Viscount " , all in the vicinity of Iceland . Her next victim was the Empire Endurance on 20 April , southwest of Rockall ; also lost when this ship went down were two launches which were being carried as deck cargo : " ML - 1003 " and " M - 1037 " . 3rd , 4th and 5th and patrols . These sorties were conducted in mid - Atlantic but were uneventful . 6th patrol . " U - 73 " entered the Mediterranean Sea via the heavily defended Straits of Gibraltar on 14 January 1942 during her sixth patrol . Rosenbaum claimed to have sunk a destroyer in February , but post - war records offer no confirmation . She docked at La Spezia in Italy on 12 February . 7th patrol . The submarine was attacked by a Bristol Blenheim of No . 203 Squadron RAF about north northwest of Derna in Libya on 22 March 1942 . The damage was such that the boat was unable to dive and had to return to La Spezia on 26 March 1942 . The U - boat was under repair at La Spezia for four months . 8th patrol . On 11 August 1942 she sank the aircraft carrier during Operation Pedestal ( supplying Malta ) . Rosenbaum was awarded the Knight ' s Cross and sent to command the Black Sea U - boat flotilla . 9th patrol . First watch officer Horst Deckert was promoted to command " U - 73 " . He was the son of German - American parents living in Chicago and had joined " U - 73 " s crew as a midshipman in 1940 . " U - 73 " was depth - charged during an unsuccessful attack on Operation Torch ( the invasion of French North Africa ) troopships on 7 November . On 10 November , " U - 73 " missed the battleship with four torpedoes launched at a range of five kilometers . She also damaged the " Lalande " off Oran on 14 November 1942 . This ship was under repair until June 1943 . 10th and 11th patrols . " U - 73 " was damaged in an air attack on 5 December 1942 and forced to return to base . The boat was also attacked by a British Lockheed Hudson of 500 Squadron on 27 December 1942 ; damage was slight - the Hudson was shot down . She sank the 7 , 200 - ton American Liberty ship SS " Arthur Middleton " from the convoy UGS 3 on 1 January 1943 miles off Oran . 12th patrol . As allied forces prepared for Operation Husky ( the invasion of Sicily ) , " U - 73 " sank the 1 , 600 - ton British freighter " Brinkburn " off Oran on 21 June 1943 and damaged the 8 , 300 - ton Royal Navy oiler RFA " Abbeydale " on 28 June 1943 . The " Brinkburn " exploded with such force that damaged food cans and two 75mm shells , still in their transit boxes , were found on the U - boat ' s bridge . The boat tied up at Toulon in France on 1 July 1943 . 13th patrol . Patrol number thirteen took " U - 73 " to Sicily ; she reached the Straits of Messina ( between the island and the Italian mainland ) , on 19 August 1943 . 14th patrol . " U - 73 " was attacked by the British submarine southeast of Toulon on 30 October 1943 ( just before the end of her patrol ) . The torpedo missed . 15th patrol and loss . " U - 73 " found the convoy GUS - 24 off Oran on 16 December 1943 and torpedoed the 7 , 200 - ton American Liberty ship SS " John S . Copley " . As the damaged vessel returned to port , the destroyers , and left Mers - el - Kebir to find the U - boat . She was located by sonar at 18 : 15 . Hull turbulence made the U - boat ' s hydrophones ineffective at the speed " U - 73 " was leaving the area , so she was unaware of the destroyers until " Woolsey " s pattern of depth charges exploded below the submarine at 18 : 39 . Sea water poured in between the bow torpedo tubes and from a salt water inlet valve for the diesel engine cooling system . All ballast tanks were blown to bring " U - 73 " to the surface as inflowing water exceeded pumping capacity . " U - 73 " surfaced in darkness at 19 : 27 and men manned the heavy machine guns . The destroyers promptly detected her on radar and illuminated the submarine with searchlights . She sank by the stern following a brief exchange of gunfire , 34 of the crew were rescued by 22 : 10 . Three of " Woolsey " s crew were wounded by machine gun fire and sixteen of the U - boat crew perished . Summary of raiding history . * carried by the < br > * * carried by the " Arthur Middleton " Sensors . Radar . " U - 73 " was one of the few U - boats to be fitted with a FuMO 61 " Hohentwiel " U - Radar system . It was installed on the starboard side of the conning tower .