|Ordered||19 June 1942|
|Builder||Blohm & Voss, Hamburg|
|Laid down||1 December 1942|
|Launched||4 March 1944|
|Commissioned||24 April 1944|
|Fate||Scuttled on 4 May 1945|
|Class and type||Type XVIIA submarine|
|Draught||4.3 m (14 ft 1 in)|
German submarine U-793 was a Type XVIIA U-boat of Nazi Germany's Kriegsmarine during the Second World War. She was one of a small number of U-boats fitted with Hellmuth Walter's high test peroxide propulsion system, which offered a combination of air-independent propulsion and high submerged speeds. She spent the war as a trials vessel and was scuttled on 4 May 1945 in the Audorfer See, near Rendsburg.
The U-793 was laid down on 1 December 1942 at the Blohm & Voss, Hamburg, as yard number 456. She was launched on 4 March 1944 and commissioned under the command of Oberleutnant zur See Günther Schauenburg on 24 April 1944.
When she was completed, the submarine was 39.05 metres (128 ft 1 in) long overall, with a beam of 4.50 metres (14 ft 9 in) and a draught of 4.30 metres (14 ft 1 in). She was assessed at 309 long tons (314 t) submerged. The submarine was powered by one Deutz SAA 8M517 supercharged 8-cylinder diesel engine producing a total of 210–230 metric horsepower (150–170 kW; 210–230 shp) for use while surfaced and one Walter gas turbines producing a total of 2,500 metric horsepower (1,800 kW; 2,500 shp) for use while submerged. She had one shaft and one propeller. The submarine had a maximum surface speed of 9 knots (17 km/h; 10 mph) and a maximum submerged speed of 25 knots (46 km/h; 29 mph) using the HTP drive. When submerged, the U-boat could operate for 127 nautical miles (235 km; 146 mi) at 20 knots (37 km/h; 23 mph) on her HTP system and when surfaced, she could travel 2,910 nautical miles (5,390 km; 3,350 mi) at 8.5 knots (15.7 km/h; 9.8 mph).
The submarine was fitted with two 53.3 cm (21 in) torpedo tubes (All fitted at the bow) and four torpedoes. The boat had a complement of 12 men.
U-793 did not undertake any war patrols and was instead assigned as a trials boat at first to the 8th U-boat Flotilla, followed by the 5th U-boat Flotilla.
The U-793 was scuttled on 4 May 1945 at 1.30am in the Audorfer See (Kaiser Wilhelm Canal), near Rendsburg during Operation Regenbogen.
The wreck of U-793 lay atuntil 26 May 1945, when she was lifted by the British and taken to the Howaldtswerke in Kiel to be examined. She was first raised as a British prize and used for trials, but was soon torn down for parts and finally scrapped.