German submarine U-433

German submarine U-433 was a Type VIIC U-boat     built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 4 January 1940 by Schichau-Werke, Danzig as yard number 1474, launched on 15 March 1941 and commissioned on 24 May 1941 under Oberleutnant zur See Hans Ey.

Design
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-433 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-433 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 an anti-aircraft gun. The boat had a complement of between forty-four and sixty.

Service history
The boat's career began with training at 3rd U-boat Flotilla on 24 May 1941, and continuing with active service on 1 August 1941 as part of the 3rd Flotilla for the remainder of her service.

In two patrols she damaged one merchant ship, for a total of.

Wolfpacks
U-433 took part in two wolfpacks, namely
 * Markgraf (28 August – 16 September 1941)
 * Arnauld (8–16 November 1941)

Fate
U-433 was sunk on 16 November 1941 in the Mediterranean E of Gibraltar, in position 36.21667°N, -4.7°W, by depth charges and gunfire from Royal Navy corvette HMS Marigold (K87). There were 6 dead and 38 survivors.