SM UB-27

SM UB-27 was a German Type UB II submarine or U-boat in the German Imperial Navy (Kaiserliche Marine) during World War I. The U-boat was ordered on 30 April 1915 and launched on 10 February 1916. She was commissioned into the German Imperial Navy on 23 February 1916 as SM UB-27. UB-27 sank 11 ships in 17 patrols for a total of.

Design
A Type UB II submarine, UB-27 had a displacement of 265 t when at the surface and 291 t while submerged. She had a total length of 36.13 m, a beam of 4.36 m, and a draught of 3.66 m. The submarine was powered by two Benz six-cylinder diesel engines producing a total 270 PS, two Siemens-Schuckert electric motors producing 280 PS, and one propeller shaft. She was capable of operating at depths of up to 50 m.

The submarine had a maximum surface speed of 8.90 kn and a maximum submerged speed of 5.72 kn. When submerged, she could operate for 45 nmi at 4 kn; when surfaced, she could travel 7200 nmi at 5 kn. UB-26 was fitted with two 50 cm torpedo tubes, four torpedoes, and one 5 cm SK L/40 deck gun. She had a complement of twenty-one crew members and two officers and a thirty-second dive time.

Service history
On 29 April 1916 in the North Sea about 15 nmi south-east of Souter Point near Whitburn, County Durham, UB-27 opened with her deck gun fire at SS Wandle, an "flat-iron" collier of the Wandsworth, Wimbledon and Epsom District Gas Company. The collier engaged the submarine and survived. Afterwards in Britain it was believed Wandle had sunk UB-27 and the master, G.E.A. Mastin, and his crew were celebrated.

UB-27 disappeared after 22 July 1917. HMS Halcyon (1894) reported ramming and depth charging a U-boat on 29 July 1917. A postwar German study concluded that it was possible that Halcyon sank UB-27 at 52.78333°N, 2.4°W.