SS Uhenfels SS " Uhenfels was a steam merchant ship operated initially by the German shipping firm " Deutsche Dampfschiffahrts - Gesellschaft Hansa " , and then shortly after the start of the Second World War by the British Elder Dempster Lines Ltd , as SS " Empire Ability . She was sunk under this name in 1941 by a German U - boat . Construction , early career and capture . The " Uhenfels " was built in 1931 at the Bremen yards of Deschimag Werk Weser , being completed for service with DDG Hansa in March that year . She operated for several years under this name , until the outbreak of the Second World War saw her outside Germany . She made a number of attempts to sail back , before making her third attempt , departing Lourenço Marques on 13 October 1939 , bound for Germany and disguised as the Dutch merchant " Aagtekerk " . She was carrying opium , worth £250 , 000 , as well as cotton and hides . Three of her crew deserted before the ship sailed from Lourenço Marques . They made their way to Zululand , where they were arrested by the police and brought to Maritzburg . After being fined , they were interned in South Africa for the duration of the war . During her crossing of the Atlantic she ran into Force K , a number of British ships that had been deployed in search of the German commerce raider the " Admiral Graf Spee " . Attached to the force was the aircraft carrier , whose aircraft had spotted another disguised German merchant the previous month , when on 9 October they had sighted the German tanker " Altmark " . The " Altmark " had been disguised as the American " Delmar " , and consequently had escaped unmolested . The " Uhenfels " was not so fortunate . Detected on 5 November the aircraft reported the German ship , and the destroyer was directed to secure the German merchant . The crew attempted to scuttle the ship but a boarding party from the " Hereward " was able to prevent this . The captured ship was brought into Freetown the following day . The 61 crew were marched off to a prison camp ashore , defiantly singing Nazi songs . By the time she had been captured the " Uhenfels " was running short of food . " Uhenfels " was then taken to Gibraltar for drydocking and inspection , arriving on 18 March . She arrived at London on 5 April 1940 , the first captured German vessel to arrive in port there . Her cargo consisted maize , palm kernel s and other foodstuffs from the West Indies . She was also carrying 122 tanned sheepskin s , which were offered for sale by public tender " in prize " . SS " Empire Ability " . The " Uhenfels " was taken into service with the British , being renamed " Empire Ability " in April 1940 by the Ministry of War Transport . She was assigned to be operated by Elder Dempster Lines and sailed in a number of convoys . On 23 October 1940 she was among those bombed and damaged by German aircraft while waiting in Gare Loch for a convoy to assemble . On 27 February 1941 the Italian submarine " Bianchi " attacked convoy OB 290 , and claimed to have scored a probable hit on the " Empire Ability " . The " Empire Ability " was not a part of this convoy however . " Empire Ability " was a part of convoy SL 78 though , when it was attacked by on 27 June 1941 . " Empire Ability " was carrying a cargo of 7 , 725 tons of sugar , 238 tons of rum , 400 tons of kernels and 35 tons of fibre , and was under the command of her master Herbert Flowerdew . The convoy was then 200 miles southeast of the Azores . " U - 69 " s commander , Jost Metzler , made several attacks , sinking the at 0149 hours , and hitting the " Empire Ability " at 0237 hours with a single torpedo . The " Empire Ability " caught fire and was abandoned , sinking at 21 minutes after having been hit . Only two people were killed , with a total of 107 crew , gunners , military personnel and assorted passengers successfully abandoning ship . The survivors were picked up by the SS " Amerika " and transferred to the corvette . They were subsequently landed at Milford Haven . Those lost on " Empire Ability " are commemorated at the Tower Hill Memorial , London . Official number and code letters . Official Numbers were a forerunner to IMO Numbers . " Empire Ability " had the UK Official Number 167423 . " Uhenfels " used the Code Letters DOKS . " Empire Ability " used the Code Letters GQJY .