German submarine U-846 was a Type IXC/40 U-boat built for Nazi Germany's Kriegsmarine during World War II.
German Type IXC/40 submarines were slightly larger than the original Type IXCs. U-846 had a displacement of 1144t when at the surface and 1257t while submerged. The U-boat had a total length of 76.76m (251.84feet), a pressure hull length of 58.75m (192.75feet), a beam of 6.86m (22.51feet), a height of 9.6m (31.5feet), and a draught of 4.67m (15.32feet). The submarine was powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of 4400PS for use while surfaced, two Siemens-Schuckert 2 GU 345/34 double-acting electric motors producing a total of 1000shp for use while submerged. She had two shafts and two 1.92abbr=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-846 was fitted with six 53.30NaN0 torpedo tubes (four fitted at the bow and two at the stern), 22 torpedoes, one 10.52NaN2 SK C/32 naval gun, 180 rounds, and a 3.7sp=usNaNsp=us SK C/30 as well as a 2sp=usNaNsp=us C/30 anti-aircraft gun. The boat had a complement of forty-eight.
U-846 was ordered on 20 January 1941 from DeSchiMAG AG Weser in Bremen under the yard number 1052. Her keel was laid down on 21 July 1942. The U-boat was launched the following year on 17 February 1943. On 29 May she was commissioned into service under the command of Oberleutnant zur See der Reserve Berthold Hashagen (Crew 37) in 4th U-boat Flotilla.
After completing training, U-846 was transferred to 10th U-boat Flotilla and left Kiel for the North Atlantic on 4 December 1943. Joining groups Amrum and Rügen at the end of the month, returning without success to Lorient on 3 March 1944. U-846 left Lorient again on 29 April. During an air attack on 2 May she managed to shoot down one aircraft, Halifax 'H' of No. 58 Squadron RAF. The next day another aircraft attacked the U-boat without success, but early on 4 May a bomb hit from a Wellington, 'M' of 407 Squadron RCAF, sank U-846 in position 46.1°N -29°W.