German submarine U-1229 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-1229 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-1229 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 3.7cm (01.5inches) Flak M42 as well as two twin 2sp=usNaNsp=us C/30 anti-aircraft guns. The boat had a complement of forty-eight.
U-1229 was ordered on 14 October 1941 from Deutsche Werft AG Weser in Hamburg-Finkenwerder under the yard number 392. Her keel was laid down on 2 March 1943 and was launched on 22 October 1943. About three months later she was commissioned into service under the command of Kapitänleutnant Arnim Zinke (Crew 31) in the 31st U-boat Flotilla on 13 January 1944.
After completing training and work-up for deployment, U-1229 was transferred to the 10th U-boat Flotilla for front-line service on 1 August 1944. The U-boat left Kiel on 13 July 1944 for the first and only war patrol operating unsuccessfully against Allied shipping in the North Atlantic and off the coast of Canada. A special mission to infiltrate an Abwehr agent into the United States failed, when U-1229 was spotted south of Newfoundland by a Radar-equipped aircraft from and subsequently attacked by several more aircraft over a period of two hours. Having been heavily damaged in the initial air attack, U-1229 attempted to escape under water but was forced to surface again as poisonous fumes started to develop from the damaged battery sections. While the crew was abandoning ship, the U-boat was strafed by several aircraft resulting in the death of numerous crew members, including Zinke. In total 18 crew members died while 41 survivors were picked up by a US destroyer after seven hours in the water. One of the survivors was the experienced German intelligence agent Oskar Mantel.[1]