SM UB-25 was a German Type UB II submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The U-boat was ordered on 30 April 1915 and launched on 9 October 1915. She was commissioned into the German Imperial Navy on 11 December 1915 as SM UB-25.[1] The submarine was lost in a collision with in Kiel harbour on 17 March 1917. She was raised on 22 March 1917 by the salvage ship and served on as a training boat until surrendered to the Allies at Harwich on 26 November 1918 in accordance with the requirements of the Armistice with Germany. She was sold by the British Admiralty to George Cohen on 3 March 1919 for £750 (excluding her engines), and was broken up at Canning Town.[2]
A Type UB II submarine, UB-25 had a displacement of 265t when at the surface and 291t while submerged. She had a total length of 36.13m (118.54feet), a beam of 4.36m (14.3feet), and a draught of 3.66m (12.01feet). The submarine was powered by two Benz six-cylinder diesel engines each producing a total 267PS, a Siemens-Schuckert electric motor producing 210kW, 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-25 was fitted with two torpedo tubes, four torpedoes, and one 5sp=usNaNsp=us SK L/40 deck gun. She had a complement of twenty-one crew members and two officers and a thirty-second dive time.