|Ordered:||5 June 1941|
|Builder:||DeSchiMAG AG Weser, Bremen|
|Laid down:||16 November 1942|
|Launched:||25 May 1943|
|Commissioned:||16 September 1943|
|Fate:||Sank due to unknown causes in April 1945|
|Class and type:||Type IXC/40 submarine|
|Height:||9.60 m (31 ft 6 in)|
|Draught:||4.67 m (15 ft 4 in)|
|Test depth:||230 m (750 ft)|
|Complement:||4 officers, 44 enlisted|
German submarine U-857 was a Type IXC/40 U-boat of Nazi Germany's Kriegsmarine built for service during the Second World War. She was ordered on 5 June 1941, laid down on 16 November 1942, and launched on 25 May 1943. For her operational lifespan, she was commanded by Kapitänleutnant Rudolf Premauer and had a crew complement of 59.
German Type IXC/40 submarines were slightly larger than the original Type IXCs. U-857 had a displacement of 1,144 tonnes (1,126 long tons) when at the surface and 1,257 tonnes (1,237 long tons) while submerged. The U-boat had a total length of 76.76 m (251 ft 10 in), a pressure hull length of 58.75 m (192 ft 9 in), a beam of 6.86 m (22 ft 6 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.67 m (15 ft 4 in). The submarine was powered by two MAN M 9 V 40/46 supercharged four-stroke, nine-cylinder diesel engines producing a total of 4,400 metric horsepower (3,240 kW; 4,340 shp) for use while surfaced, two Siemens-Schuckert 2 GU 345/34 double-acting electric motors producing a total of 1,000 shaft horsepower (1,010 PS; 750 kW) for use while submerged. She had two shafts and two 1.92 m (6 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).
The submarine had a maximum surface speed of 18.3 knots (33.9 km/h; 21.1 mph) and a maximum submerged speed of 7.3 knots (13.5 km/h; 8.4 mph). When submerged, the boat could operate for 63 nautical miles (117 km; 72 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 13,850 nautical miles (25,650 km; 15,940 mi) at 10 knots (19 km/h; 12 mph). U-857 was fitted with six 53.3 cm (21 in) torpedo tubes (four fitted at the bow and two at the stern), 22 torpedoes, one 10.5 cm (4.13 in) SK C/32 naval gun, 180 rounds, and a 3.7 cm (1.5 in) Flak M42 as well as two twin 2 cm (0.79 in) C/30 anti-aircraft guns. The boat had a complement of forty-eight.
She undertook three patrols, the first was for training. She sank two ships for a total tonnage of 15,259 gross register tons (GRT), and damaged one other ship on her last two patrols. She sank Belgian Airman on 14 April 1945, Swiftscout on 18 April 1945 and damaged Katy on 23 April 1945.
U-857 went missing in April 1945 in the North Atlantic Ocean off the east coast of the United States. All hands were lost, and no wreckage was found.
The U-boat had been claimed to have been sunk by depth charge hedgehogs off the coast of Massachusetts in April 1945 by USS Gustafson and was also thought to have been possibly sunk by USS Coffman. However more recent commentary surmised that Gustafson had not hit her, and her loss is currently unexplained. Her wreck currently lies off of Cape Cod.
Summary of raiding history
|Date||Ship Name||Nationality||Tonnage (GRT)||Fate|
|14 April 1945||Belgian Airman||Belgium||6,959||Sunk|
|18 April 1945||Swiftscout||United States||8,300||Sunk|
|23 April 1945||Katy||Norway||6,825||Damaged|
- Gröner 1991, p. 68.
- Helgason, Guðmundur. "The Type IXC/40 boat U-857". German U-boats of WWII - uboat.net. Retrieved 7 December 2014.
- Sinking of U 548
- Niestlé, Axel "German U-boat Losses During World War II: Details of Destruction" (Annapolis: Naval Institute Press, 1998)
- "USCG-U-857". 26 January 2012. Retrieved 19 December 2012.
- Ship Wreck Data
- Helgason, Guðmundur. "Ships hit by U-857". German U-boats of WWII - uboat.net. Retrieved 13 February 2014.
- Busch, Rainer; Röll, Hans-Joachim (1999). German U-boat commanders of World War II : a biographical dictionary. Translated by Brooks, Geoffrey. London, Annapolis, Md: Greenhill Books, Naval Institute Press. ISBN 1-55750-186-6.
- Busch, Rainer; Röll, Hans-Joachim (1999). Deutsche U-Boot-Verluste von September 1939 bis Mai 1945 [German U-boat losses from September 1939 to May 1945]. Der U-Boot-Krieg (in German). IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2.
- Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.
- Helgason, Guðmundur. "The Type IXC/40 boat U-857". German U-boats of WWII - uboat.net. Retrieved 2 February 2015.
- Ship Wreck Data