SM UB - 42 SM " UB - 42 " was a Type UB II submarine or U - boat for the German Imperial Navy ( ) during World War I . " UB - 42 " operated in the Mediterranean and the Black Seas during the war . She was broken up at Malta in 1920 . " UB - 42 " was ordered in July 1915 and was laid down at the AG Weser shipyard in Bremen in September . " UB - 42 " was in length and displaced between , depending on whether surfaced or submerged . She was equipped to carry a complement of four torpedoes for her two bow torpedo tube s and had an deck gun . As part of a group of six submarines selected for Mediterranean service , " UB - 42 " was broken into railcar sized components and shipped to Pola where she was assembled , launched and commissioned in March 1916 . In 21 patrols during the war , " UB - 42 " sank ten ships of , captured one 97 - ton vessel as a prize , and damaged a British . In October 1916 , " UB - 42 " delivered five Georgians who had gold to help finance a Georgian independence movement . After the surrender of the Ottoman Empire in late October 1918 , " UB - 42 " fled to Sevastopol , where she was surrendered in November . " UB - 42 " was taken to Malta , where she was broken up in 1920 . Design and construction . The German UB II design improved upon the design of the UB I boats , which had been ordered in September 1914 . In service , the UB I boats were found to be too small and too slow . A major problem was that , because they had a single propeller shaft / engine combo , if either component failed , the U - boat became almost totally disabled . To rectify this flaw , the UB II boats featured twin propeller shafts and twin engines ( one shaft for each engine ) , which also increased the U - boat ' s top speed . The new design also included more powerful batteries , larger torpedo tubes , and a deck gun . As a UB II boat , " U - 47 " could also carry twice the torpedo load of her UB I counterparts , and nearly ten times as much fuel . To contain all of these changes the hull was larger , and the surface and submerged displacement was more than double that of the UB I boats . The German Imperial Navy ordered " UB - 42 " from AG Weser of Bremen on 31 July 1915 as one of a series of six UB II boats ( numbered from " UB - 42 " to ) . " UB - 42 " was long and abeam . She had a single hull with saddle tank s and had a draft of when surfaced . She displaced while submerged but only on the surface . The submarine was equipped with twin diesel engines and twin electric motors — for surfaced and submerged running , respectively — that drove twin propeller shafts . " UB - 42 " had a surface speed of up to and could go as fast as while underwater . The U - boat could carry up to of diesel fuel , giving her a range of at . Her electric motors and batteries provided a range of at while submerged . " UB - 42 " was equipped with two bow torpedo tube s and could carry four torpedo es . The U - boat was also armed with a SK L / 40 deck gun . " UB - 42 " was laid down on 3 September 1915 . As one of six U - boats selected for service in the Mediterranean while under construction , " UB - 42 " was broken into railcar - sized components and shipped overland to the Austro - Hungarian port of Pola . Shipyard workers from Weser assembled the boat and her five sisters at Pola , where she was launched on 4 March 1916 . Service career . SM " UB - 42 " was commissioned into the German Imperial Navy on 23 March 1916 under the command of " Kapitänleutnant " Fritz Wernicke . " UB - 42 " , Wernicke ' s first U - boat command , was assigned to the Navy ' s Pola Flotilla ( ) . Although the flotilla was based in Pola , the site of the main Austro - Hungarian Navy base , boats of the flotilla operated out of the Austro - Hungarian base at Cattaro which was located farther south and closer to the Mediterranean . German U - boats typically returned to Pola only for repairs . The first months of service for " UB - 42 " proved unsuccessful ; the U - boat sank no ships while in the Pola Flotilla . After Germany ' s conquest of Romania ( see " Romania during World War I " ) , the German Imperial Navy had sufficient fuel oil for submarines located in the Black Sea . " UB - 42 " and three of her sister ships in the Pola Flotilla were ordered to Constantinople and , en route , had to navigate through the Dardanelles , which had been heavily mined by the Allies in the middle of 1916 . " UB - 42 " joined the Constantinople Flotilla ( ) on 16 August . The German submarines in the Black Sea accomplished little , sinking only six ships between August 1916 and the end of the year . " UB - 42 " sank half of the six in September and October . On 3 September , Wernicke and " UB - 42 " achieved their first success when they sank the Russian transport " Peter Darcy " in the Black Sea . The 731 - ton ship was headed from Constantza to Odessa when torpedoed by " UB - 42 " . The 150 - ton Russian vessel " St . Nikolei " was sunk at the entrance to Karkinit Bay on 5 October , and the 2 , 891 - ton " Czarita " was sunk two weeks later off Cape Midia . In April 1917 , " UB - 42 " was operating in the Mediterranean when she made attacks on three ships . On 14 April , Wernicke torpedoed the British off Alexandria , damaging the 1 , 200 t vessel . Two days later , " UB - 42 " sank the 86 - ton Egyptian sailing ship off Gaza and , a week after that , sank a 15 - ton Italian sailing vessel , " Boro " , east of Rhodes in the Aegean Sea . On 14 May , Wernicke was succeeded by " Kapitänleutnant " Kurt Schwarz as commander of " UB - 42 " . The 27 - year - old Schwarz , who had previously commanded the Type UB I boat , led " UB - 42 " to sink her largest ship , , on 24 June . The 8 , 912 - ton former Leyland Line steamer was in use as a troopship , carrying 800 troops and horses when Schwarz sent her down southeast of Skyros in the Aegean . Three of " Cestrian " s crewmen died in the attack and , according to R . H . Gibson and Maurice Prendergast , " splendid discipline " among the embarked troops was the sole reason that none were lost . In early October , " UB - 42 " had returned to the Black Sea , when she was ordered to deliver five Georgians with gold to finance a Georgian independence movement . While remaining in the Black Sea , " UB - 42 " sank the sailing ships " Agios Georgios " on 10 October , and " Francesco Patrino " in November . On 22 November , she torpedoed the 1 , 086 - ton " Siracusy " while the latter was at anchor off the Georgian coast . " UB - 46 " also shelled Tuapse while in the northern Black Sea . " Kapitänleutnant " Erich von Rohrscheidt assumed command of " UB - 42 " on 6 April 1918 , and six week later , led the U - boat in capturing the motor sailing vessel " Sergij " as a prize six weeks later off Novorossisk . In September , " Kapitänleutnant " Hans Georg Lübbe ( who had succeeded Herbert Nolde after his two - month stint as commander of " UB - 42 " ) led the U - boat in sinking her final ship . On the night of 7 / 8 September , the 1 , 833 - ton Italian steamer " Vicenza " was sent down south of Salonica . " UB - 42 " s commanding officer was changed twice more before the end of the war , but the submarine sank no more ships . After the signing of the Armistice of Mudros on 30 October ended the war for the Ottoman Empire , the four remaining U - boats of the Constantinople Flotilla — " UB - 14 " , " UB - 42 " , , and — fled to Sevastopol . There they were surrendered on 26 November . " UB - 42 " was broken up at Malta in 1920 . Ships sunk or damaged . < nowiki > * < / nowiki > damaged but not sunk < br > < nowiki > * * < / nowiki > captured as a prize