SM U-81
| History | |
|---|---|
 German Empire | |
| Name | U-81 |
| Ordered | 23 June 1915 |
| Builder | Germaniawerft, Kiel |
| Yard number | 251 |
| Laid down | 31 August 1915 |
| Launched | 24 June 1916 |
| Commissioned | 22 August 1916 |
| Fate | 1 May 1917 - Torpedoed W of Ireland at 51°33′N 13°38′W / 51.550°N 13.633°W by HM Sub E54. 31 dead, seven survivors.[1] |
| General characteristics [2] | |
| Displacement |
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| Length |
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| Beam |
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| Height | 8.00 m (26 ft 3 in) |
| Draught | 4.02 m (13 ft 2 in) |
| Installed power | |
| Propulsion | 2 shafts, 2 × 1.70 m (5 ft 7 in) propellers |
| Speed |
|
| Range |
|
| Test depth | 50 m (160 ft) |
| Complement | 4 officers, 31 enlisted |
| Armament |
|
| Service record | |
| Part of: |
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| Commanders: |
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| Operations: | 5 patrols |
| Victories: | |
SM U-81[Note 1] was one of the 329 submarines serving in the Imperial German Navy (Kaiserliche Marine) in World War I. U-81 was engaged in naval warfare and took part in the First Battle of the Atlantic.[1]
U-81 had one 10.5 cm gun with 140–240 rounds.[1] On 8 February 1917 she torpedoed Mantola 143 nautical miles (265 km; 165 mi) off Fastnet, forcing her crew and passengers to abandon her. She then shelled the drifting hulk until being chased away by the Acacia-class sloop HMS Laburnum. Mantola sank the next day.[4][5] HMS E54 sank U-81 by torpedo west of Ireland on 1 May 1917. 31 of U-81's crew were killed; seven survived.[1]
Design[edit]
German Type U 81 submarines were preceded by the shorter Type UE I submarines. U-81 had a displacement of 808 tonnes (795 long tons) when at the surface and 946 tonnes (931 long tons) while submerged.[2] She had a total length of 70.06 m (229 ft 10 in), a pressure hull length of 55.55 m (182 ft 3 in), a beam of 6.30 m (20 ft 8 in), a height of 8 m (26 ft 3 in), and a draught of 4.02 m (13 ft 2 in). The submarine was powered by two 2,400 metric horsepower (1,800 kW; 2,400 shp) engines for use while surfaced, and two 1,200 metric horsepower (880 kW; 1,200 shp) engines for use while submerged. She had two propeller shafts. She was capable of operating at depths of up to 50 metres (160 ft).[2]
The submarine had a maximum surface speed of 16.8 knots (31.1 km/h; 19.3 mph) and a maximum submerged speed of 9.1 knots (16.9 km/h; 10.5 mph).[2] When submerged, she could operate for 56 nautical miles (104 km; 64 mi) at 5 knots (9.3 km/h; 5.8 mph); when surfaced, she could travel 11,220 nautical miles (20,780 km; 12,910 mi) at 8 knots (15 km/h; 9.2 mph). U-81 was fitted with four 50-centimetre (20 in) torpedo tubes (one at the starboard bow and one starboard stern), twelve to sixteen torpedoes, and one 10.5 cm (4.1 in) SK L/45 deck gun. She had a complement of thirty-five (thirty-one crew members and four officers).[2]
Summary of raiding history[edit]
| Date | Name | Nationality | Tonnage[Note 2] | Fate[6] |
|---|---|---|---|---|
| 1 December 1916 | Douglas |  Sweden
|
1,177 | Sunk |
| 19 December 1916 | Nystrand |  Norway
|
1,397 | Sunk |
| 2 February 1917 | Songdal | Norway
|
2,090 | Sunk |
| 3 February 1917 | Port Adelaide |  United Kingdom
|
8,181 | Sunk |
| 4 February 1917 | Maria |  Kingdom of Italy
|
992 | Sunk |
| 5 February 1917 | Wartenfels |  United Kingdom
|
4,511 | Sunk |
| 7 February 1917 | Gravina | United Kingdom
|
1,242 | Sunk |
| 8 February 1917 | Mantola | United Kingdom
|
8,253 | Sunk |
| 10 February 1917 | Netherlee | United Kingdom
|
4,227 | Sunk |
| 12 February 1917 | Hugo Hamilton | Sweden
|
2,577 | Sunk |
| 10 March 1917 | Algol | Norway
|
988 | Sunk |
| 10 March 1917 | Skreien | Norway
|
415 | Sunk |
| 13 March 1917 | Coronda | United Kingdom
|
2,733 | Sunk |
| 14 March 1917 | Paignton | United Kingdom
|
2,017 | Sunk |
| 18 March 1917 | Pola | United Kingdom
|
3,061 | Sunk |
| 18 March 1917 | Trevose | United Kingdom
|
3,112 | Sunk |
| 19 March 1917 | Alnwick Castle | United Kingdom
|
5,900 | Sunk |
| 19 March 1917 | Frinton | United Kingdom
|
4,194 | Sunk |
| 22 March 1917 | Attika | Norway
|
2,306 | Sunk |
| 25 March 1917 | C. Sundt | Norway
|
1,105 | Sunk |
| 25 March 1917 | Garant | Norway
|
735 | Sunk |
| 25 March 1917 | Laly | Norway
|
1,880 | Sunk |
| 24 April 1917 | Amulree | United Kingdom
|
1,145 | Sunk |
| 25 April 1917 | Glenesk | Norway
|
1,369 | Sunk |
| 25 April 1917 | Heathfield | United Kingdom
|
1,643 | Sunk |
| 25 April 1917 | Invermay | United Kingdom
|
1,471 | Sunk |
| 27 April 1917 | Uranus | Kingdom of Italy
|
3,978 | Sunk |
| 28 April 1917 | Jose De Larrinaga | United Kingdom
|
5,017 | Sunk |
| 28 April 1917 | Terence | United Kingdom
|
4,309 | Sunk |
| 30 April 1917 | Elisabeth |  Denmark
|
217 | Damaged |
| 1 May 1917 | Dorie | United Kingdom
|
3,264 | Damaged |
| 1 May 1917 | San Urbano | United Kingdom
|
6,458 | Sunk |
References[edit]
Notes[edit]
- ^ "SM" stands for "Seiner Majestät" (English: His Majesty's) and combined with the U for Unterseeboot would be translated as His Majesty's Submarine.
- ^ Tonnages are in gross register tons
Citations[edit]
- ^ a b c d e Helgason, Guðmundur. "WWI U-boats: U 81". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 25 January 2010.
- ^ a b c d e Gröner 1991, pp. 12–14.
- ^ Helgason, Guðmundur. "WWI U-boat commanders: Raimund Weisbach". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 20 January 2015.
- ^ Helgason, Guðmundur. "Gairsoppa". Ships hit by U-boats. Retrieved 11 January 2024.
- ^ "SS Mantola WWI shipwreck reveals silver haul". BBC News. 10 October 2011. Retrieved 11 October 2011.
- ^ Helgason, Guðmundur. "Ships hit by U 81". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 20 January 2015.
Bibliography[edit]
- Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. Vol. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.
Shipwrecks and maritime incidents in May 1917 | |
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| Shipwrecks |
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| Other incidents |
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