SM U-81

SM U-81 was one of the 329 submarines serving in the Imperial German Navy (Kaiserliche Marine) in World War I. U-81 was engaged in naval warfare and took part in the First Battle of the Atlantic.

U-81 had one 10.5 cm gun with 140-240 rounds. On 8 February 1917 she torpedoed the SS Mantola 143 nautical miles (265 km; 165 mi) off Fastnet, forcing her crew to abandon her. She then shelled the drifting hulk until being chased away by the Acacia-class sloop HMS Laburnum.Laburnam took the floating hulk under tow, but the line parted in the rough seas, and Mantola was left to sink, which she did on 9 February.

Design

German Type U 81 submarines were preceded by the shorter Type UE I submarines. U-81 had a displacement of 808 tonnes (795 long tons) when at the surface and 946 tonnes (931 long tons) while submerged. It had a total length of 229 ft 10 in (70.05 m), a pressure hull length of 182 ft 3 in (55.55 m), a beam of 20 ft 8 in (6.30 m), a height of 26 ft 3 in (8.00 m), and a draught of 13 ft 2 in (4.01 m). The submarine was powered by two 2,400 metric horsepower (1,800 kW; 2,400 shp) engines for use while surfaced, and two 1,200 metric horsepower (880 kW; 1,200 shp) engines for use while submerged. It had two 1.7 m (5.6 ft) propeller shafts. It was capable of operating at depths of up to 50 metres (160 ft).

German submarine U-81

U-81 may refer to one of the following German submarines:

German submarine U-81 (1941)

German submarine U-81 was a Type VIIC U-boat of the navy (Kriegsmarine) of Nazi Germany during World War II.

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-81 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged. She had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two MAN M 6 V 40/46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. She had two shafts and two 1.23 m (4 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).