U-9, a typical Type IIB boat
|Ordered:||2 February 1935|
|Laid down:||1 August 1935|
|Launched:||14 January 1936|
|Commissioned:||1 February 1936|
|Fate:||Scuttled 10 September 1944, off the coast of Turkey in the Black Sea|
|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|
|Identification codes:||M 29 241|
German submarine U-20 was a Type IIB U-boat of Nazi Germany's Kriegsmarine. Her keel was laid down on 1 August 1935, by Germaniawerft of Kiel as yard number 550. She was commissioned on 1 February 1936. During World War II, she conducted operations against enemy shipping.
U-20 went on 16 war patrols, sinking 16 ships totalling 39,637 GRT and damaging one more of 1,846 GRT.
German Type IIB submarines were enlarged versions of the original Type IIs. U-20 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-20 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.
1st, 2nd and 3rd patrols
U-20's first three patrols involved observation (in August 1939) and the laying of mines in the North Sea and off the British east coast. She would start in Kiel and finish in Wilhelmshaven; then reverse the process.
4th and 5th patrols
She sank Magnus about 40 nmi (74 km; 46 mi) east northeast of Peterhead in Scotland. The ship went down in 90 seconds; there was only one survivor. She also sank Ionian and Willowpool in November and December respectively, with mines laid in November.
The boat sank Sylvia northeast of Aberdeen on her fifth sortie on 13 October 1940.
6th - 8th patrols
U-20 sank a steady number of ships on her sixth and seventh patrols, (her eighth foray was relatively quiet), but a series of changes were on the way.
She was transferred to the U-Ausbildungsflottille as a school boat on 1 May 1940, then the Black Sea, avoiding the heavy British presence at Gibraltar and throughout the Mediterranean by being transported in sections along the Danube to the Romanian port of Galați. She was then re-assembled by the Romanians at the Galați shipyard and sent to her new home in the Black Sea so she could serve with the 30th U-boat Flotilla.
9th and 10th patrols
The boat's first patrol in the new environment, but her ninth overall, almost ended in disaster when she tried to torpedo a Soviet submarine chaser; the vessel responded by dropping eight depth charges. U-20 was obliged to stay submerged for four hours and returned to base with various mechanical failures.
Near the end of sally number ten, a crew member from U-19 who had been taken sick, was transferred to U-20 on 4 August 1943. The boat docked at Constanta on the 7th.
11th - 14th patrols
The boat sank Pestel on 19 June 1944 off Trabzon. The Soviets reported that this ship was sunk in Turkish territorial waters.
She also sank the Soviet landing craft DB-26 on 26 June with gunfire and demolition charges.
16th patrol and fate
On 3 February 2008, The Daily Telegraph newspaper reported that U-20 had been discovered by Selçuk Kolay, a Turkish marine engineer, in 80 feet (24 m) of water off the coast of the Turkish city of Karasu.
Summary of raiding history
|29 November 1939||Ionian||United Kingdom||3,114||Sunk (mine)|
|9 December 1939||Magnus||Denmark||1,339||Sunk|
|10 December 1939||Føina||Norway||1,674||Sunk|
|10 December 1939||Willowpool||United Kingdom||4,815||Sunk (mine)|
|13 January 1940||Sylvia||Sweden||1,524||Sunk|
|27 January 1940||England||Denmark||2,319||Sunk|
|27 January 1940||Faro||Norway||844||Total loss|
|27 January 1940||Friedensborg||Denmark||2,094||Sunk|
|27 January 1940||Hosanger||Denmark||1,591||Sunk|
|29 February 1940||Maria Rosa||Italy||4,211||Sunk|
|1 March 1940||Mirella||Italy||5,340||Sunk|
|29 November 1943||Peredovik||Soviet Union||1,846||Damaged|
|16 January 1944||Vaijan Kutur'e||Soviet Union||7,602||Total loss|
|7 April 1944||Rion||Soviet Union||184||Sunk (mine)|
|19 June 1944||Pestel||Soviet Union||1,850||Sunk|
|24 June 1944||DB-26||Soviet Navy||9||Sunk|
- Kemp 1999, p. 217.
- Gröner 1991, pp. 39–40.
- Steel and Ice: The U-boat Battle in the Arctic and Black Sea 1941-45, Chapter 5 - The Black Sea: War in the South 1942-43, 5th page
- Adolf Hitler's "Lost fleet" found in Black Sea, The Telegraph, Retrieved 2010-12-27
- Helgason, Guðmundur. "Ships hit by U-20". German U-boats of WWII - uboat.net. Retrieved 29 December 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.
- Kemp, Paul (1999). U-Boats Destroyed - German Submarine Losses in the World Wars. London: Arms & Armour. ISBN 1-85409-515-3.
- Helgason, Guðmundur. "The Type IIB boat U-20". German U-boats of WWII - uboat.net. Retrieved 6 December 2014.
- Hofmann, Markus. "U 20". Deutsche U-Boote 1935-1945 - u-boot-archiv.de (in German). Retrieved 6 December 2014.
- "U-boat Archive - U-boat KTB - U-20's 14th War Patrol". Retrieved 13 April 2017.