SM UB - 2 SM " UB - 2 " was a German Type UB I submarine or U - boat in the German Imperial Navy ( ) during World War I . She sank eleven ships during her career and was broken up in Germany in 1920 . " UB - 2 " was ordered in October 1914 and was laid down at the Germaniawerft shipyard in Kiel in November . " UB - 2 " was a little more than in length and displaced between , depending on whether surfaced or submerged . She carried two torpedo es for her two bow torpedo tube s and was also armed with a deck - mounted machine gun . She was launched and commissioned as SM " UB - 2 " in February 1915 . When " UB - 2 " sailed to join the Flanders Flotilla in May 1915 , she became the only member of her class to not be shipped by rail to Antwerp to join the unit . While in the flotilla , " UB - 2 " sank eleven British ships of under the command of Werner Fürbringer . The U - boat was assigned to the Baltic Flotilla in March 1916 relegated to a training role from December that same year . At the end of the war , " UB - 2 " was deemed unseaworthy and unable to surrender at Harwich with the rest of Germany ' s U - boat fleet . She remained in Germany where she was broken up by Stinnes in February 1920 . Design and construction . After the German Army ' s rapid advance along the North Sea coast in the earliest stages of World War I , the German Imperial Navy found itself without suitable submarines that could be operated in the narrow and shallow environment off Flanders . Project 34 , a design effort begun in mid - August 1914 , produced the Type UB I design : a small submarine that could be shipped by rail to a port of operations and quickly assembled . Constrained by railroad size limitations , the UB I design called for a boat about long and displacing about with two torpedo tube s . " UB - 2 " was part of the initial allotment of eight submarines — numbered to — ordered on 15 October from Germaniawerft of Kiel , just shy of two months after planning for the class began . " UB - 2 " was laid down by Germaniawerft on 1 November , one the first two boats of the class started . She was launched at Kiel on 13 February 1915 . As built , " UB - 2 " was long , abeam , and had a draft of . She had a single Daimler 4 - cylinder diesel engine for surface travel , and a single Siemens - Schuckert electric motor for underwater travel , both attached to a single propeller shaft . Her top speeds were , surfaced , and , submerged . At more moderate speeds , she could sail up to on the surface before refueling , and up to submerged before recharging her batteries . Like all boats of the class , " UB - 2 " was rated to a diving depth of , and could completely submerge in 33 seconds . " UB - 2 " was armed with two torpedo es in two bow torpedo tube s . She was also outfitted for a single machine gun on deck . " UB - 2 " s standard complement consisted of one officer and thirteen enlisted men . Service career . The submarine was commissioned into the German Imperial Navy as SM " UB - 2 " on 20 February under the command of " Kapitänleutnant " Werner Fürbringer , a 26 - year - old native of Braunschweig , and underwent trials in German home waters . " UB - 2 " sailed from Germany to Flanders to join the Flanders Flotilla ( ) on 10 May 1915 , and was the only UB I or UC I boat in the flotilla to not be shipped to Antwerp by rail . When " UB - 2 " joined the flotilla , Germany was in the midst of its first submarine offensive , begun in February . During this campaign , enemy vessels in the German - defined war zone ( ) , which encompassed all waters around the United Kingdom ( including the English Channel ) , were to be sunk . Vessels of neutral countries were not to be attacked unless they definitively could be identified as enemy vessels operating under a false flag . The UB I boats of the Flanders Flotilla were initially limited to patrols in the Hoofden , the southern portion of the North Sea between the United Kingdom and the Netherlands . On 9 and 10 June , while patrolling in this area southeast of Lowestoft , " UB - 2 " sank six British fishing smack s with a combined tonnage of just under , the largest being " Intrepid " of 59 tons . All six of the smacks — sailing vessels traditionally rigged with red ochre sails — were stopped , boarded by crewmen from " UB - 2 " , and sunk with explosives . After " UB - 2 " s sister boat pioneered a route around past British anti - submarine net s and mine s in the Straits of Dover in late June , boats of the flotilla began to patrol the western English Channel . " UB - 2 " , , and soon followed with patrols in the Channel . Even though none of the boats sank any ships , by successfully completing their voyages they helped further prove the feasibility of defeating the British countermeasures in the Straits of Dover . On 28 August , " UB - 2 " was patrolling in the Corton – Yarmouth area when she sank the British trawler " Miura " . At 297 tons , " Miura " bested " Intrepid " as the largest vessel sunk by " UB - 2 " to - date . Early the following month , " UB - 2 " sank another two fishing smacks east - southeast of Lowestoft : the 57 - ton " Constance " , and the 44 - ton " Emanuel " . Three days later , " UB - 2 " sank 47 - ton smack " Boy Ernie " about east of Cromer . As with the six vessels sunk in June , all three were stopped by " UB - 2 " and sunk with explosives . Germany ' s submarine offensive was suspended on 18 September by the chief of the " Admiralstab " , Admiral Henning von Holtzendorff , In response to American demands after German submarines had sunk the Cunard Line steamer in May 1915 and other high profile sinkings in August and September . Holtzendorff ' s directive from ordered all U - boats out of the English Channel and the South - Western Approaches and required that all submarine activity in the North Sea be conducted strictly along prize regulations . " UB - 2 " did not sink any vessels over the next four months . The German Imperial Navy began its second submarine offensive in February 1916 , declaring , among other provisions , that all enemy vessels in the war zone were to be destroyed without warning . On 26 February 1916 , " UB - 2 " torpedoed and sank the cargo ship " Arbonne " , in what was ultimately her last wartime success . The British steamer — at , the largest ship sunk by " UB - 2 " — went down with a loss of all fourteen of her crew . In early March , " Kapitänleutnant " Fürbringer was succeeded by the former commander of , " Kapitänleutnant " Karl Neumann , who had been in the same cadet class as Fürbringer . Fürbringer went on to command six other U - boats , and was responsible for sinking nearly 100 , 000 tons of shipping . In 1933 he published a memoir of his World War I U - boat service , " Alarm ! Tauchen ! ! : U - boot in kampf und sturm " , which included an overview of his career , including his time on " UB - 2 " . By early February , the Flanders Flotilla was beginning to receive the newer , larger Type UB II boats . " UB - 2 " was transferred into the Baltic Flotilla ( ) about a week after Neumann took command . Boats of the Baltic flotilla were based at either Kiel , Danzig , or Libau , but where " UB - 2 " was stationed during this time is not reported in sources . While " UB - 2 " was in the Baltic Flotilla , Neumann was succeeded by " Oberleutnant zur See " Thomas Bieber in April , who was in turn succeeded by " Oberleutnant zur See " Harald von Keyserlingk in July . In early December , Keyserlingk was reassigned from " UB - 2 " to , and " UB - 2 " was transferred to training duties . According to authors R . H . Gibson and Maurice Prendergast , submarines assigned to training duties were " war - worn craft " unfit for service . At the end of the war , the Allies required all German U - boats to be sailed to Harwich for surrender . " UB - 2 " was one of eight U - boats deemed unseaworthy and allowed to remain in Germany . " UB - 2 " was broken up by Stinnes on 3 February 1920 .