German submarine U-988 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II.
She was laid down on 2 October 1942 by Blohm & Voss, Hamburg as yard number 188, launched on 3 June 1943 and commissioned on 15 July 1943 under Oberleutnant zur See Erich Dobberstein.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-988 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 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 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).The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a maximum submerged speed of 7.6 knots (14.1 km/h; 8.7 mph). When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph). U-988 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm (3.46 in) SK C/35 naval gun, 220 rounds, and one twin 2 cm (0.79 in) C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
U-988′s career began on 15 July 1943 with training as part of the 5th U-boat Flotilla. On 8 September 1943, she collided with U-983 in the Baltic Sea north of Loba (54°46′N 17°14′E). As a result of the collision, U-983 sank with the loss of five of her 43 crew.U-988 began active service on 1 June 1944 as part of the 7th U-boat Flotilla.
U-988 took part in no wolfpacks.
U-988 was sunk on 29/30 June 1944 in the English Channel west of Guernsey at 49°37′N 03°41′W at dawn by the Royal Navy frigates HMS Essington, HMS Cooke, HMS Duckworth, and HMS Domett, after being damaged by and Royal Air Force Liberators of No. 244 Squadron.