SM UC-31

History
German Empire
NameUC-31
Ordered29 August 1915[1]
BuilderAG Vulcan, Hamburg[2]
Yard number70[1]
Launched7 August 1916[1]
Commissioned2 September 1916[1]
FateSurrendered, 26 November 1918; broken up, 1922[1]
General characteristics [3]
Class and typeType UC II submarine
Displacement
  • 400 t (390 long tons), surfaced
  • 480 t (470 long tons), submerged
Length
Beam
  • 5.22 m (17 ft 2 in) o/a
  • 3.65 m (12 ft) pressure hull
Draught3.68 m (12 ft 1 in)
Propulsion
Speed
  • 11.6 knots (21.5 km/h; 13.3 mph), surfaced
  • 6.7 knots (12.4 km/h; 7.7 mph), submerged
Range
  • 10,040 nmi (18,590 km; 11,550 mi) at 7 knots (13 km/h; 8.1 mph), surfaced
  • 53 nmi (98 km; 61 mi) at 4 knots (7.4 km/h; 4.6 mph), submerged
Test depth50 m (160 ft)
Complement26
Armament
Notes48-second diving time
Service record
Part of:
  • I Flotilla
  • 10 December 1916 – 14 June 1918
  • Flandern II Flotilla
  • 14 June – 7 October 1918
  • I Flotilla
  • 7 October – 11 November 1918
Commanders:
  • Oblt.z.S. / Kptlt. Otto von Schrader[4]
  • 2 September 1916 – 20 July 1917
  • Kptlt. Kurt Siewert[5]
  • 21 July 1917 – 14 June 1918
  • Oblt.z.S. Willy Stüben[6]
  • 15 June – 11 November 1918
Operations: 13 patrols
Victories:
  • 35 merchant ships sunk
    (50,258 GRT)
  • 3 auxiliary warships sunk
    (759 GRT)
  • 3 merchant ships damaged
    (8,016 GRT)
  • 1 warship damaged
    (1,025 tons)

SM UC-31 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The U-boat was ordered on 29 August 1915 and was launched on 7 August 1916. She was commissioned into the German Imperial Navy on 2 September 1916 as SM UC-31.[Note 1] In 13 patrols UC-31 was credited with sinking 38 ships, either by torpedo or by mines laid. UC-31 was surrendered on 26 November 1918 and broken up at Canning Town in 1922.[1]

Design

A Type UC II submarine, UC-31 had a displacement of 400 tonnes (390 long tons) when at the surface and 480 tonnes (470 long tons) while submerged. She had a length overall of 49.45 m (162 ft 3 in), a beam of 5.22 m (17 ft 2 in), and a draught of 3.68 m (12 ft 1 in). The submarine was powered by two six-cylinder four-stroke diesel engines each producing 250 metric horsepower (180 kW; 250 shp) (a total of 500 metric horsepower (370 kW; 490 shp)), two electric motors producing 460 metric horsepower (340 kW; 450 shp), and two propeller shafts. She had a dive time of 48 seconds and was capable of operating at a depth of 50 metres (160 ft).[3]

The submarine had a maximum surface speed of 11.6 knots (21.5 km/h; 13.3 mph) and a submerged speed of 6.7 knots (12.4 km/h; 7.7 mph). When submerged, she could operate for 53 nautical miles (98 km; 61 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 10,040 nautical miles (18,590 km; 11,550 mi) at 7 knots (13 km/h; 8.1 mph). UC-31 was fitted with six 100 centimetres (39 in) mine tubes, eighteen UC 200 mines, three 50 centimetres (20 in) torpedo tubes (one on the stern and two on the bow), seven torpedoes, and one 8.8 cm (3.5 in) Uk L/30 deck gun. Her complement was twenty-six crew members.

Summary of raiding history

Date Name Nationality Tonnage[Note 2] Fate[7]
31 December 1916 Protector  United Kingdom 200 Sunk
4 January 1917 Lonclara  United Kingdom 1,294 Sunk
25 January 1917 O. B. Suhr  Denmark 1,482 Sunk
28 January 1917 Alexandra  United Kingdom 179 Sunk
29 January 1917 Shamrock  United Kingdom 173 Sunk
29 January 1917 Thistle  United Kingdom 167 Sunk
31 January 1917 Ravensbourne  United Kingdom 1,226 Sunk
24 February 1917 Beneficent  United Kingdom 1,963 Sunk
29 March 1917 Kathleen Lily  United Kingdom 521 Sunk
30 March 1917 Harberton  United Kingdom 1,443 Sunk
4 April 1917 Helga  Denmark 839 Sunk
5 April 1917 N. J. Fjord  Denmark 1,425 Sunk
6 April 1917 HMT Strathrannoch  Royal Navy 215 Sunk
11 April 1917 Quaggy  United Kingdom 993 Sunk
12 April 1917 Dina Hinderika  Netherlands 200 Sunk
12 April 1917 Neptunus  Netherlands 209 Sunk
12 April 1917 Union  Denmark 152 Sunk
12 April 1917 Voorwaarts  Netherlands 147 Sunk
14 April 1917 Spray  United Kingdom 1,072 Sunk
15 April 1917 Brothertoft  United Kingdom 155 Sunk
6 May 1917 Poseidon I  Netherlands 98 Sunk
8 May 1917 HMY Zarefah  Royal Navy 279 Sunk
17 May 1917 Aspen  Sweden 3,103 Damaged
17 May 1917 Viken  Sweden 1,825 Sunk
30 June 1917 Lady of the Lake  United Kingdom 51 Sunk
1 July 1917 Amstelland  Netherlands 5,404 Sunk
2 July 1917 Thirlby  United Kingdom 2,009 Sunk
3 July 1917 Matador  United Kingdom 3,642 Sunk
7 August 1917 Othalia  Sweden 1,205 Damaged
11 August 1917 Holar  Denmark 548 Sunk
12 August 1917 Bogatyr  Denmark 1,360 Sunk
8 September 1917 Newholm  United Kingdom 3,399 Sunk
11 September 1917 Cento  United Kingdom 3,708 Damaged
16 September 1917 Quatre Freres  France 53 Sunk
13 November 1917 Amelie  Belgium 1,135 Sunk
13 November 1917 Australbush  Australia 4,398 Sunk
19 November 1917 HMT Morococala  Royal Navy 265 Sunk
21 January 1918 Teelin Head  United Kingdom 1,718 Sunk
29 January 1918 Ethelinda  United Kingdom 3,257 Sunk
1 April 1918 Ardglass  United Kingdom 4,617 Sunk
5 April 1918 Cyrene  United Kingdom 2,904 Sunk
10 April 1918 HMS Magic  Royal Navy 1,025 Damaged

References

Notes

  1. ^ "SM" stands for "Seiner Majestät" (English: His Majesty's) and combined with the U for Unterseeboot would be translated as His Majesty's Submarine.
  2. ^ Merchant ship tonnages are in gross register tons. Military vessels are listed by tons displacement.

Citations

  1. ^ a b c d e f Helgason, Guðmundur. "WWI U-boats: UC 31". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 22 February 2009.
  2. ^ Tarrant, p. 173.
  3. ^ a b Gröner 1991, pp. 31–32.
  4. ^ Helgason, Guðmundur. "WWI U-boat commanders: Otto von Schrader (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 February 2015.
  5. ^ Helgason, Guðmundur. "WWI U-boat commanders: Kurt Siewert (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 February 2015.
  6. ^ Helgason, Guðmundur. "WWI U-boat commanders: Willy Stüben". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 February 2015.
  7. ^ Helgason, Guðmundur. "Ships hit by UC 31". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 February 2015.

Bibliography

  • Bendert, Harald (2001). Die UC-Boote der Kaiserlichen Marine 1914-1918. Minenkrieg mit U-Booten (in German). Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0758-7.
  • 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.
  • Gardiner, Robert; Gray, Randal, eds. (1985). Conway's All the World's Fighting Ships 1906–1921. Annapolis, Maryland: Naval Institute Press. ISBN 978-0-87021-907-8. OCLC 12119866.
  • Tarrant, V. E. (1989). The U-Boat Offensive: 1914–1945. Annapolis, Maryland: Naval Institute Press. ISBN 978-0-87021-764-7. OCLC 20338385.