German submarine U - 573 German submarine " U - 573 " was a Type VIIC U - boat built for the Nazi German Kriegsmarine for service during World War II . Her keel was laid down 8 June 1940 at the Blohm + Voss yard in Hamburg as ' werk ' 549 . She was launched on 17 April 1941 and commissioned on 5 June with " Kapitänleutnant " Heinrich Heinsohn ( 12 February 1910 – 6 May 1943 ) in command . Heinsohn commanded her for her entire career in the Kriegsmarine . In May 1941 he had arranged that the city of Landeck in Tyrol adopted the submarine within the then popular sponsorship programme ( Patenschaftsprogramm ) , organising gifts and holidays for the crew , earning her the honorary name U - 573 " Landeck " . The boat began her service career as part of the 3rd U - boat Flotilla when she conducted training ; on 1 September 1941 she commenced operations with that flotilla . She was transferred to the 29th flotilla , also for operations , on 1 January 1942 . Operational career . " U - 573 " conducted four war patrols , sinking just one ship . 1st , 2nd and 3rd patrols . Her operational career began with her departure from Kiel on 15 September 1941 . She entered the Atlantic via the North Sea and the gap between Iceland and the Faroe Islands . She almost reached the Labrador coast before heading for St . Nazaire in occupied France , docking on 15 November . " U - 573 " s second patrol involved the boat slipping past the heavily defended Strait of Gibraltar into the Mediterranean , where she sank the Norwegian " Hellen " ( 5 , 289 tons ) with two torpedoes on 21 December 1941 . She arrived at Pola in Croatia on 30 December . Her third sortie was relatively uneventful , starting and finishing in Pola between 2 February and 6 March 1942 . 4th patrol and internment . On 29 April 1942 , " U - 573 " was attacked with depth charge s by Lockheed Hudson s of No . 233 Squadron RAF , northwest of Algiers . Seriously damaged , she limped north to Spain , arriving in Cartagena on 2 May . International agreements allowed ships in neutral ports 24 hours to make emergency repairs before they were to be interned . The Spanish authorities granted " U - 573 " a three - month period for repairs , which prompted several strong protests from the British Embassy in Madrid . On 19 May Heinsohn flew from Madrid to Stuttgart , then travelled on to Berlin , in order to discuss the situation with the " Kriegsmarine " . He returned by train via Hendaye ( in southwest France ) on 28 May . Realizing that even three months would not be enough to repair the boat , the " Kriegsmarine " sold the vessel to Spain for 1 . 5 million Reichsmark s . On 2 August 1942 , at 10 am , ( one day before the three - month period was due to expire ) , the Spanish navy commissioned the boat as the " G - 7 " . " U - 573 " s crew suffered no casualties during her career in the " Kriegsmarine " . The men had been interned in Cartagena and were gradually released in groups of two or three . The last five members of the crew left with " Kptlt . " Heinsohn on 13 February 1943 . He returned to the " Kriegsmarinearsenal " in Gdynia , then German - annexed Poland , In March he was ordered to Brest , then in German - occupied France to take command of " U - 438 " , and died with all his crew two months later . " G - 7 " s repairs were completed in 1947 . In 1958 Arca - Filmproduktion GmbH rented " G - 7 " to take part in the semi - fictitious movie " U 47 – Kapitänleutnant Prien " , partially based on his patrol to Scapa Flow , where he sank HMS Royal Oak . " G - 7 " was renamed " S - 01 " in 1961 ; she served in the Spanish Navy until 1970 . One other U - boat was interned in Spain during World War II : " U - 760 " .