SM UB-31 was a German Type UB II submarine or U-boat in the German Imperial Navy () during World War I. The U-boat was ordered on 22 July 1915 and launched on 16 November 1915. She was commissioned into the German Imperial Navy on 25 March 1916 as SM UB-31.
The submarine sank 27 ships in 25 patrols. UB-31 was depth charged and sunk by British warships , , and in the English Channel on 2 May 1918. Alternatively she may have been sunk by a mine on that date.
Design
A German Type UB II submarine, UB-31 had a displacement of when at the surface and while submerged. She had a total length of , a beam of , and a draught of . The submarine was powered by two Benz six-cylinder diesel engines producing a total , two Siemens-Schuckert electric motors producing , and one propeller shaft. She was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, she could operate for at ; when surfaced, she could travel at . UB-31 was fitted with two torpedo tubes, four torpedoes, and one Uk L/30 deck gun. She had a complement of twenty-one crew members and two officers and a 42-second dive time.
Summary of raiding history
References
Notes
Citations
Bibliography
External links
Croche, Paulo (2014) 'UB-31 Folkestone, Kent: Archaeological Report', Wessex Archaeology Historic England project to research First World War submarine wrecks.