German submarine U-99 (1940)

U-52, a typical Type VIIB boat
History
Nazi Germany
Name:	U-99
Ordered:	15 December 1937
Builder:	Germaniawerft, Kiel
Yard number:	593
Laid down:	31 March 1939
Launched:	12 March 1940
Commissioned:	18 April 1940
Fate:	Scuttled, 17 March 1941, south-east of Iceland. Three dead and 40 survivors
General characteristics
Class and type:	Type VIIB submarine
Displacement:	753 tonnes (741 long tons) surfaced 857 t (843 long tons) submerged
Length:	66.50 m (218 ft 2 in) o/a 48.80 m (160 ft 1 in) pressure hull
Beam:	6.20 m (20 ft 4 in) o/a 4.70 m (15 ft 5 in) pressure hull
Height:	9.50 m (31 ft 2 in)
Draught:	4.74 m (15 ft 7 in)
Installed power:	2,800–3,200 PS (2,100–2,400 kW; 2,800–3,200 bhp) (diesels) 750 PS (550 kW; 740 shp) (electric)
Propulsion:	2 shafts 2 × diesel engines 2 × electric motors
Range:	9,400 nmi (17,400 km; 10,800 mi) at 10 knots (19 km/h; 12 mph) surfaced 90 nmi (170 km; 100 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth:	220 m (720 ft) Crush depth: 230–250 m (750–820 ft)
Complement:	4 officers, 40–56 enlisted
Sensors and processing systems:	Gruppenhorchgerät
Armament:	5 × 53.3 cm (21 in) torpedo tubes (four bow, one stern) 14 × torpedoes or 26 TMA mines 1 × 8.8 cm (3.46 in) deck gun (220 rounds) 1 × 2 cm (0.79 in) anti-aircraft gun
Service record
Part of:	Kriegsmarine: 7th U-boat Flotilla
Identification codes:	M 17 046
Commanders:	Otto Kretschmer
Operations:	Eleven 1st patrol: 18–25 June 1940 2nd patrol: 27 June – 21 July 1940 3rd patrol: 25 July – 5 August 1940 4th patrol: 4–25 September 1940 5th patrol: 13–22 October 1940 6th patrol: 30 October – 8 November 1940 7th patrol: 27 November – 12 December 1940 8th patrol: 22 February – 17 March 1941
Victories:	35 ships sunk (totaling 198,218 GRT) three auxiliary warships sunk - 46,440 GRT five ships damaged - 37,965 GRT one ship taken as a prize - 2,136 GRT

German submarine U-99 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. She was laid down on 31 March 1939 at the Friedrich Krupp Germaniawerft in Kiel as yard number 593. She was launched on 12 March 1940 under the command of Korvettenkapitän Otto Kretschmer and was assigned to the 7th U-boat Flotilla based in Kiel and later in St Nazaire.

U-99 was one of the most successful German U-boats in the war, sinking 38 ships for a total tonnage of 244,658 gross register tons (GRT) of Allied shipping in eight patrols. She damaged five more ships and took one vessel as a prize.

German Type VIIB submarines were preceded by the shorter Type VIIA submarines. U-99 had a displacement of 753 tonnes (741 long tons) when at the surface and 857 tonnes (843 long tons) while submerged. She had a total length of 66.50 m (218 ft 2 in), a pressure hull length of 48.80 m (160 ft 1 in), a beam of 6.20 m (20 ft 4 in), a height of 9.50 m (31 ft 2 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two Germaniawerft F46 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 BBC 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).