German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-989 displaced 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-989 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and one twin 2sp=usNaNsp=us C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
The boat's career began with training at 5th U-boat Flotilla on 22 July 1943, followed by active service on 1 February 1944 as part of the 9th Flotilla. On 1 October 1944 she transferred to 33rd Flotilla for the remainder of her service.
In five patrols she sank one merchant ship, for a total of and damaged one other.
U-989 took part in three wolfpacks, namely:
U-989 was sunk on 14 February 1945 in the North Atlantic in position 61.6°N -36°W, by depth charges from,, and . All hands were lost.
| Date | Ship Name | Nationality | Tonnage (GRT) | Fate[1] | |
|---|---|---|---|---|---|
| 23 August 1944 | Louis Kossuth |  United States | 7,176 | Damaged | |
| 26 August 1944 | Ashmun J Clough |  United Kingdom | 1,791 | Sunk |