German submarine U-743

German submarine U-743 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine built for service during World War II. Her keel was laid down on 30 May 1942 by Schichau-Werke of Danzig. She was commissioned on 15 May 1943 with Oberleutnant zur See Helmut Kandzior in command.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-743 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, two AEG GU 460/8–27 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-743 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 two twin 2 cm C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.

Fate
On 20 August 1944 U-743 entered Trondheim for schnorkel repairs. She left the next day and was never heard from again. On 10 September 1944 U-743 was declared missing.

Previously recorded fate
U-743 was originally thought to have been sunk on 9 September 1944 at position 55.45°N, -11.41°W by depth charges from HMS Portchester Castle (K362) and HMS Helmsdale (K253). This attack actually resulted in the sinking of GS U-484.