SM U - 14 ( Austria - Hungary ) SM " U - 14 or U - XIV " was a U - boat or submarine of the Austro - Hungarian Navy during the First World War . She was launched in 1912 as the French " Curie " ( Q 87 ) , but captured and rebuilt for service in the Austro - Hungarian Navy . At war ' s end , the submarine was returned to France and restored to her former name . " Curie " was launched in July 1912 at Toulon and completed in 1914 . She measured just under long and displaced nearly on the surface and just over when submerged . At the outbreak of the First World War in August 1914 , " Curie " was assigned to duty in the Mediterranean . In mid - December , " Curie " s commander conceived a plan to infiltrate the Austro - Hungarian Navy ' s main base at Pola , but during the 20 December attempt , the vessel became ensnared in harbor defenses . Two Austro - Hungarian ships sank " Curie " , killing three of her crew ; the remainder were taken prisoner . The Austro - Hungarian Navy , which had a small and largely obsolete U - boat fleet , immediately began salvage efforts and succeeded in raising the lightly damaged submarine in early February 1915 . After a refit , the boat was commissioned as SM " U - 14 " in June , but had little success early in her career . When her commander fell ill in October , he was replaced by Georg Ritter von Trapp . " U - 14 " was damaged by a depth charge attack in February 1916 , and underwent an extensive modernization through November . Resuming duty under von Trapp , " U - 14 " sank her first ship in April 1917 , but had her most successful patrol in August , when she sank five ships — including , reportedly the largest cargo ship in the world — in a six - day span . In January 1918 , von Trapp was replaced as commander , but neither of his two successors were able to match his accomplishments . In all , " U - 14 " sank 11 ships with a combined gross register tonnage of nearly 48 , 000 tons . Returned to France at the end of the war , she rejoined the French Navy in July 1919 under her former name of " Curie " . She remained in service until 1928 and was scrapped in 1929 . Design and construction . " Curie " was a part of the 16 - boat authorized under the 1906 program . The " Brumaire " - class boats were diesel - powered versions of the steam - powered submarines ( which had been authorized the year before ) , and , like the " Pluviôse " boats , were named after either months of the French Republican Calendar or scientists . " Curie " was named after Pierre and Marie Curie . The " Bruimaire " - class was designed by French naval designer Maxime Laubeuf and featured a double hull . The boats were long , abeam , with a draft of when surfaced . They had a displacement of surfaced and submerged . " Curie " , like the other 15 submarines of the class , featured one bow torpedo tube and could carry as many as eight torpedo es . As built , " Curie " did not have a deck gun . The " Brumaire " - class featured twin propeller shafts driven by two French license - built MAN 6 - cylinder diesel engines on the surface , or by two electric motors when submerged . " Curie " s diesel engines generated a total of and could move the submarine at up to on the surface ; her electric motors generated and could propel the boat up to submerged . While traveling on the surface at , " Curie " had a range of ; the submarine ' s range while submerged was at . " Curie " was laid down at the Arsenal de Toulon and launched on 18 July 1912 , completed by 1914 , and commissioned into the French Navy . French career and sinking . Like all the " Brumaire " - class submarines , " Curie " began her First World War service in the Mediterranean , and was one of the first French submarines to appear in the Adriatic . On 17 December 1914 , " Curie " , at the insistence of her French - Irish commander Gabriel O ' Byrne , departed her base in the Ionian Sea under tow by the French armored cruiser . Depositing her charge from Pola , the site of the Austro - Hungarian Navy ' s main base , " Jules Michelet " departed , leaving " Curie " to proceed to the Austro - Hungarian base . " Curie " arrived the next day and began reconnoitering the entrance to the harbor . O ' Byrne observed the entrance and exit paths of Austro - Hungarian vessels and plotted a course through the deployed defensive mine s . On 19 December , O ' Byrne took " Curie " in to observe the anti - submarine net that ran across the opening in a long , defensive breakwater built to keep submarines from infiltrating the naval base . Believing that he had accounted for all of the defensive measures , " O ' Byrne " took " Curie " to a depth of early on 20 December and , attempting an incursion into the harbor , heard the sounds of chains and wires dragging on the submarine ' s hull . When the sounds stopped after half a minute , O ' Byrne brought " Curie " up to periscope depth to discover that he had only penetrated the outer net . " Curie " s forward momentum carried her into the second net where she became " inextricably entangled " . When the submarine , still trapped in the net , was forced to surface for fresh air , " Curie " came under fire from the Austro - Hungarian destroyer and torpedo boat " Tb 63 T " which quickly sank her . Three of the twenty - six men on board were killed in the attack ; the survivors — who included " Curie " s commander , O ' Byrne — were all taken prisoner . Salvage and Austro - Hungarian career . At the beginning of the First World War , the Austro - Hungarian Navy ' s U - boat fleet consisted of six largely experimental submarines of three classes . The Navy had five larger , more modern submarines ( what would have been the " U - 7 " class ) under construction in Germany at the outbreak of war , but when the Navy became convinced that delivery of the " U - 7 " boats would be impossible , they were sold to Germany in November 1914 . Amidst Austro - Hungarian efforts to replace the now - unavailable " U - 7 " boats , the largely intact " Curie " , resting at a depth of , became the focus of salvage efforts . Beginning on 21 December , the day after " Curie " s sinking , salvage crews raised the submarine in stages , finally bringing her to the surface on 2 February 1915 . The former " Curie " , now assigned the designation " U - 14 " , was reconditioned and commissioned into the Austro - Hungarian Navy under the command of " Korvettenkapitän " Otto Zeidler on 1 June . Zeidler remained in command until he fell ill , and was replaced in mid - October by " Linienschiffsleutnant " Georg Ritter von Trapp . Under Zeidler ' s command and the first months of von Trapp ' s command , " U - 14 " had no successes . In early February 1916 , " U - 14 " joined for a patrol near Durazzo . " U - 4 " came closest to scoring a success when she narrowly missed hitting , a British on 7 February . " U - 14 " survived a depth charge attack , but made it back to port with all of her externally mounted torpedoes crushed and both fuel tanks leaking . When she put in for repairs , " U - 14 " was extensively modernized in a refit that kept her in port from February to November . The submarine was given a German - style conning tower that replaced the French - designed wet lookout platform . She was equipped with more powerful diesel engines , which increased her power output from . " U - 14 " s fighting potential was further enhanced by the installation of larger fuel tanks , which nearly quadrupled her range to , up from her former maximum of . On 28 April 1917 , " U - 14 " was patrolling off the coast of Greece when she scored her first success , " Teakwood " , a 5 , 315 - ton British tanker headed from Port Arthur , Texas , to Port Said . On 3 May , on patrol in the same vicinity , von Trapp and " U - 14 " sank another ship , this one the 1 , 905 - ton Italian steamer " Antonio Sciesa " . In another patrol in July , " U - 14 " sailed on the north side of the island of Corfu while headed for Santi Quaranta , Albania . Because the harbor at Corfu was occupied by the French fleet at the time , " U - 14 " conducted a " ruse de guerre " by flying the submarine ' s former national flag , the French tricolor , in order to pass unmolested . Even though " U - 14 " s new conning tower made her look unlike any other " Brumaire " - class boat , one French patrol plane was successfully fooled by the ruse . When " U - 14 " s crew first spotted the aircraft , flying towards them from the direction of the sun , there was not enough time to submerge . As the aircraft drew near , its French markings — and its cargo of bombs — became apparent to the crew . With no other course of action possible , " U - 14 " s crew waved their hats and handkerchiefs at the plane . As the French pilot passed overhead , he returned the waves , apparently unaware of the U - boat ' s true nationality . The only success by " U - 14 " on this cruise was the sinking of " Marionga Goulandris " , a Greek steamer , near Cape Matapan . " U - 14 " s next war patrol was very successful , sinking five ships with a combined tonnage of 24 , 814 , over half of her total tonnage sunk . " U - 14 " departed from the submarine base at Cattaro on 20 August and headed through the Straits of Otranto , successfully evading the Otranto Barrage , and Allied blockade of the passageway between Italy and Albania . Heading into the Ionian Sea , von Trapp and " U - 14 " sank the French steamer " Constance " on 23 August northeast of Malta . The following day , " U - 14 " sank " Kilwinning " , a British steamer loaded with coal and a general cargo headed for Port Said . Two days after that , the British steamer " Titian " was sunk by " U - 14 " while on en route to Alexandria . " U - 14 " s next victim was the British steamer " Nairn " . The 3 , 627 - ton turret deck ship , on her way from Malta to Port Said with coal , was sunk on the night of 27 / 28 August from Benghazi . On 29 August , von Trapp sank the Italian steamer east of Malta . " Milazzo " , at 11 , 744 tons , was the largest ship sunk by " U - 14 " , and among the largest ships sunk by a U - boat in World War I . " Milazzo " , reported by " The New York Times " in 1916 as the largest cargo ship in the world , was the second - largest ship sunk by an Austro - Hungarian submarine . " U - 14 " concluded her patrol on 1 September , when she returned to Cattaro . " U - 14 " sank three more ships during a five - day span in October . On 19 October , " U - 14 " sank the British ship " Elsiston " from Malta . One person aboard " Elsiston " , which was carrying military stores between Malta and Suda Bay , was killed in the attack . Nearby , and on the same day , von Trapp sank the 3 , 618 - ton " Good Hope " , a British ship laden with iron ore for Middlesbrough . The next ship sunk by " U - 14 " was the Italian steamer " Capo di Monte " , sunk from Candia while on her way from Karachi to Malta . In January 1918 , Friedrich Schlosser replaced von Trapp as commander of " U - 14 " . Schlosser was , in turn , replaced in June by Hugo Pistel , who remained in command until the end of the war . Neither of the later commanders was able to duplicate von Trapp ' s success in " U - 14 " ; the U - boat sank no more ships through the rest of the war . After Austria - Hungary ' s surrender and the end of the First World War , " U - 14 " was returned to France and on 17 July 1919 rejoined the French Navy under her former name of " Curie " . She was stricken in 1928 and scrapped in 1929 .