German submarine U-990

German submarine U-990 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 17 October 1942 by Blohm & Voss, Hamburg as yard number 190, launched on 16 June 1943 and commissioned on 28 July 1943 under Kapitänleutnant Hubert Nordheimer.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-990 had a displacement of 769 t when at the surface and 871 t while submerged. She had a total length of 67.10 m, a pressure hull length of 50.50 m, a beam of 6.20 m, a height of 9.60 m, and a draught of 4.74 m. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2800 to 3200 PS for use while surfaced, and two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750 PS for use while submerged. She had two shafts and two 1.23 m propellers. The boat was capable of operating at depths of up to 230 m.

The submarine had a maximum surface speed of 17.7 kn and a maximum submerged speed of 7.6 kn. When submerged, the boat could operate for 80 nmi at 4 kn; when surfaced, she could travel 8500 nmi at 10 kn. U-990 was fitted with five 53.3 cm torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm SK C/35 naval gun, 220 rounds, and one twin 2 cm C/30 anti-aircraft gun. The boat had a crew sized between forty-four and sixty.

Service history
The boat's career began with training at 5th Flotilla on 28 July 1943, followed by active service on 1 January 1944 as part of the 11th Flotilla.

Wolfpacks
U-990 took part in four wolfpacks, namely:
 * Werwolf (28 January – 27 February 1944)
 * Orkan (5 – 10 March 1944)
 * Hammer (10 – 26 March 1944)
 * Blitz (2 – 4 April 1944)

Fate
U-990 was sunk on 25 May 1944 in the Norwegian Sea at 65.08333°N, 7.46667°W after being depth charged by a RAF Liberator bomber of 59 Squadron.

Sqn Ldr B. Sisson sighted U-990 on the surface at 06:23 and attacked under cover of a rain squall, dropping six depth charges. Following the attack, the submarine could be seen sinking amid a large oil slick.

There were 20 crew killed, and 33 survivors.