SM U-85

For other ships with the same name, see German submarine U-85.

SM U-85^{[Note 1]} was one of the 329 submarines serving in the Imperial German Navy in World War I. U-85 was engaged in the naval warfare and took part in the First Battle of the Atlantic.^[1]

History
German Empire
Name	U-85
Ordered	23 June 1915
Builder	Germaniawerft, Kiel
Yard number	255
Laid down	29 November 1915
Launched	22 August 1916
Commissioned	23 October 1916
Fate	Foundered in North Sea after 7 March 1917, 38 dead (all hands lost).[1]
General characteristics [2]
Displacement	808 t (795 long tons) surfaced 946 t (931 long tons) submerged
Length	70.06 m (229 ft 10 in) (o/a) 55.55 m (182 ft 3 in) (pressure hull)
Beam	6.30 m (20 ft 8 in) (oa) 4.15 m (13 ft 7 in) (pressure hull)
Height	8.00 m (26 ft 3 in)
Draught	4.02 m (13 ft 2 in)
Installed power	2 × 2,400 PS (1,765 kW; 2,367 shp) surfaced 2 × 1,200 PS (883 kW; 1,184 shp) submerged
Propulsion	2 shafts, 2 × 1.70 m (5 ft 7 in) propellers
Speed	16.8 knots (31.1 km/h; 19.3 mph) surfaced 9.1 knots (16.9 km/h; 10.5 mph) submerged
Range	11,220 nmi (20,780 km; 12,910 mi) at 8 knots (15 km/h; 9.2 mph) surfaced 56 nmi (104 km; 64 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth	50 m (160 ft)
Complement	4 officers, 31 enlisted
Armament	4 × 50 cm (19.7 in) torpedo tubes (two bow, two stern) 12-16 torpedoes 1 × 10.5 cm (4.1 in) SK L/45 deck gun (from 1917)
Service record
Part of	IV Flotilla 15 January – 12 March 1917
Commanders	Kptlt. Willy Petz[3] 23 October 1916 – 12 March 1917
Operations	3 patrols
Victories	4 merchant ships sunk (20,225 GRT) 1 merchant ship damaged (7,608 GRT)[1]

Initially, U-81 to U-83 had one 10.5 cm gun with 140-240 rounds. U-84 - U-86 on the other hand had two 8.8 cm guns. In 1917, U-84 - U-86 were refitted with a single 10.5 cm gun (240 rounds)^[1]

Design

Type U 81 submarines were preceded by the shorter Type UE I submarines. U-85 had a displacement of 808 tonnes (795 long tons) when at the surface and 946 tonnes (931 long tons) while submerged.^[2] She had a total length of 70.06 m (229 ft 10 in), a pressure hull length of 55.55 m (182 ft 3 in), a beam of 6.30 m (20 ft 8 in), a height of 8 m (26 ft 3 in), and a draught of 4.02 m (13 ft 2 in). 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. She had two propeller shafts. She was capable of operating at depths of up to 50 metres (160 ft).^[2]

The submarine had a maximum surface speed of 16.8 knots (31.1 km/h; 19.3 mph) and a maximum submerged speed of 9.1 knots (16.9 km/h; 10.5 mph).^[2] When submerged, she could operate for 56 nautical miles (104 km; 64 mi) at 5 knots (9.3 km/h; 5.8 mph); when surfaced, she could travel 11,220 nautical miles (20,780 km; 12,910 mi) at 8 knots (15 km/h; 9.2 mph). U-85 was fitted with four 50 centimetres (20 in) torpedo tubes (two at the bow and two at the stern), twelve to sixteen torpedoes, and one 10.5 cm (4.1 in) SK L/45 deck gun (from 1917). She had a complement of thirty-five (thirty-one crew members and four officers).^[2]

Summary of raiding history

Date	Name	Nationality	Tonnage[Note 2]	Fate[4]
26 January 1917	Dicax	Norway	923	Sunk
6 February 1917	Cliftonian	United Kingdom	4,303	Sunk
6 February 1917	Explorer	United Kingdom	7,608	Damaged
7 February 1917	California	United Kingdom	8,669	Sunk
7 February 1917	Vedamore	United Kingdom	6,330	Sunk