SM U - 68 SM " U - 68 was a Type U 66 submarine or U - boat for the German Imperial Navy ( ) during the First World War . She had been laid down in December 1913 as U - 9 " of the " U - 7 " class for the Austro - Hungarian Navy ( ) but was sold to Germany , along with the others in her class , in November 1914 . Under German control , the class became known as the U 66 type and the boats were renumbered ; " U - 9 " became " U - 68 " , and was redesigned and reconstructed to German specifications . She was launched in June 1915 and commissioned in August . Six days into her first war patrol , on 22 March 1916 , " U - 68 " was sunk by " Farnborough " , a British Q - ship , with all hands . " U - 68 " sank no ships in her brief career . A post - war German study found fault with " U - 68 " s captain for not following established procedures for avoiding decoy ships . Design and construction . After the Austro - Hungarian Navy had competitively evaluated three foreign submarine designs , it selected the Germaniawerft 506d design , also known as the Type UD , for its new " U - 7 " class of five submarines . The Navy ordered five boats on 1 February 1913 . The " U - 7 " class was seen by the Austro - Hungarian Navy as an improved version of its " U - 3 " class , which was also a Germaniawerft design . As designed for the Austro - Hungarian Navy , the boats were to displace on the surface and while submerged . The doubled - hulled boats were to be long ( OA ) with a beam of and a draft of . The Austrian specifications called for two shafts with twin diesel engines ( total ) for surface running at up to , and twin electric motors ( total ) for a maximum of when submerged . The boats were designed with five torpedo tubes ; four located in the bow , one in the stern . The boats ' armament was to also include a single 66 cm / 26 ( 2 . 6 in ) deck gun . " U - 9 " was laid down on 31 December 1913 , the third of the " U - 7 " boats . Her construction was slated to be complete within 29 to 33 months . Neither " U - 9 " nor any of her sister boats were complete when World War I began in August 1914 . With the boats under construction at Kiel , the Austrians became convinced that it would be impossible to take delivery of the boats , which would need to be towed into the Mediterranean past Gibraltar , a British territory . As a result , " U - 9 " and her four sisters were sold to the Imperial German Navy on 28 November 1914 . " U - 9 " was renumbered by the Germans as " U - 68 " when her class was redesignated as the Type U 66 . The Imperial German Navy had the submarines redesigned and reconstructed to German standards , which increased the surface displacement by and the submerged by . The torpedo load was increased by a third , from 9 to 12 , and the deck gun was upgraded from the gun originally specified to an one . Service career . " U - 68 " was launched on 1 June 1915 . On 17 August , SM " U - 68 " was commissioned into the " Kaiserliche Marine " under the command of " Kapitänleutnant " Ludwig Güntzel , a new submarine commander . On 29 November , " U - 68 " was assigned to the IV . " U - Halbflotille " . " U - 68 " departed the Ems on 16 March 1916 to begin her first war patrol . Headed to her assigned operating area off Britain ' s west coast , Güntzel and " U - 68 " came across " Farnborough " , a British Q - ship — in appearance unarmed — under the command of Gordon Campbell . At approximately 07 : 00 , " U - 68 " fired a torpedo at " Farnborough " and narrowly missed the ship ' s bow . " Farnborough " continued the deception and continued on at her same speed and course . At 07 : 20 , " U - 68 " surfaced about astern of " Farnborough " , moved to the ship ' s port quarter , and fired a shot across the Q - ship ' s bow . " Farnborough " stopped , blew off steam , and launched a boat to simulate a surrender . As " U - 68 " closed to , " Farnborough " raised the White Ensign , uncovered her guns and opened fire with three of her five 12 pounder ( 76 mm ) guns . The British gunners scored several hits on the U - boat out of 21 rapidly fired rounds . As " U - 68 " began to sink , Campbell steered " Farnborough " over " U - 68 " s location and dropped a depth charge that blew the bow of the submarine out of the water . As " U - 68 " began going down by the stern , " Farnborough " s gunners scored another five hits on the U - boat ' s conning tower . " U - 68 " sank with the loss of all 38 men at position off Dingle in southern Ireland . " U - 68 " sank no ships during her brief service career . A post - war German study faulted " U - 68 " s commander , " Kplt " . Güntzel , for failing to follow established procedures for dealing with neutral - flagged vessels in order to avoid decoy ships like " Farnborough " . According to the report , Güntzel had broken almost all the rules when approaching " Farnborough " . However , " Kommodore " Hermann Bauer , the commander of the German High Seas Fleet U - boats , in his post - war memoirs , reports Güntzel was an inexperienced captain and had not , contrary to usual practice , been first sent to sea under a more experienced U - boat captain to gain knowledge .