U-9, a typical Type IIB boat
|Ordered:||28 September 1937|
|Builder:||Flender Werke, Lübeck|
|Laid down:||16 April 1938|
|Launched:||20 April 1940|
|Commissioned:||28 May 1940|
|Fate:||Scuttled 2 May 1945 at Bremerhaven|
|Status:||Raised and scrapped, 1950|
|Class and type:||IIB coastal submarine|
|Height:||8.60 m (28 ft 3 in)|
|Draught:||3.90 m (12 ft 10 in)|
|Test depth:||80 m (260 ft)|
|Complement:||3 officers, 22 men|
|Victories:||No ships sunk or damaged|
German submarine U-121 was a long-lived Type IIB U-boat built during World War II for service in Nazi Germany's Kriegsmarine. U-121 spent the entire war as a training vessel and was scuttled at the end of the conflict.
U-121 was one of two Type II U-boats built at Flender Werke in Lübeck. Like her sister boat U-120 (also built in Lübeck), she was originally constructed for export to China. The advent of World War II and the increased training needs of the U-Boot-Waffe led the German high command to assign U-120 and U-121 to the training command instead.
Built for China
The Chinese Nationalist Government used 10,000,000 Marks to order two Type IIB U-boats in 1937. They also dispatched 80 men to Germany for training in submarine operations. The Japanese Government complained over this transaction, so the Chinese took their money back and the pair of Type IIB submarines joined the Kriegsmarine after the outbreak of the Second World War in Europe. They were U-120 and U-121.
German Type IIB submarines were enlarged versions of the original Type IIs. U-121 had a displacement of 279 tonnes (275 long tons) when at the surface and 328 tonnes (323 long tons) while submerged. Officially, the standard tonnage was 250 long tons (250 t), however. The U-boat had a total length of 42.70 m (140 ft 1 in), a pressure hull length of 28.20 m (92 ft 6 in), a beam of 4.08 m (13 ft 5 in), a height of 8.60 m (28 ft 3 in), and a draught of 3.90 m (12 ft 10 in). The submarine was powered by two MWM RS 127 S four-stroke, six-cylinder diesel engines of 700 metric horsepower (510 kW; 690 shp) for cruising, two Siemens-Schuckert PG VV 322/36 double-acting electric motors producing a total of 460 metric horsepower (340 kW; 450 shp) for use while submerged. She had two shafts and two 0.85 m (3 ft) propellers. The boat was capable of operating at depths of up to 80–150 metres (260–490 ft).
The submarine had a maximum surface speed of 12 knots (22 km/h; 14 mph) and a maximum submerged speed of 7 knots (13 km/h; 8.1 mph). When submerged, the boat could operate for 35–42 nautical miles (65–78 km; 40–48 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 3,800 nautical miles (7,000 km; 4,400 mi) at 8 knots (15 km/h; 9.2 mph). U-121 was fitted with three 53.3 cm (21 in) torpedo tubes at the bow, five torpedoes or up to twelve Type A torpedo mines, and a 2 cm (0.79 in) anti-aircraft gun. The boat had a complement of twentyfive.
- Blair (1996), 178-179.
- Gröner 1991, pp. 39–40.
- 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.
- Blair, Clay (1996). Hitler's U-Boat War: The Hunters 1939-1942. New York: Random House. ISBN 0-394-58839-8.
- Helgason, Guðmundur. "The Type IIB boat U-121". German U-boats of WWII - uboat.net. Retrieved 31 January 2015.
- Hofmann, Markus. "U 121". Deutsche U-Boote 1935-1945 - u-boot-archiv.de (in German). Retrieved 31 January 2015.