SM U-84

Coordinates: 51°53′N 5°44′W / 51.883°N 5.733°W / 51.883; -5.733
From Wikipedia, the free encyclopedia

History
German Empire
NameU-84
Ordered23 June 1915
BuilderGermaniawerft, Kiel
Yard number254
Laid down25 October 1915
Launched22 July 1916
Commissioned7 October 1916
Fate26 January 1918 - Possibly rammed and depth charged by PC62 in St George's Channel and sunk at 51°53′N 5°44′W / 51.883°N 5.733°W / 51.883; -5.733. 40 dead (all hands lost).[1]
General characteristics [2]
Displacement
  • 808 t (795 long tons) surfaced
  • 946 t (931 long tons) submerged
Length
Beam
  • 6.30 m (20 ft 8 in) (oa)
  • 4.15 m (13 ft 7 in) (pressure hull)
Height8.00 m (26 ft 3 in)
Draught4.02 m (13 ft 2 in)
Installed power
  • 2 × 2,400 PS (1,765 kW; 2,367 shp) surfaced
  • 2 × 1,200 PS (883 kW; 1,184 shp) submerged
Propulsion2 shafts, 2 × 1.70 m (5 ft 7 in) propellers
Speed
  • 16.8 knots (31.1 km/h; 19.3 mph) surfaced
  • 9.1 knots (16.9 km/h; 10.5 mph) submerged
Range
  • 11,220 nmi (20,780 km; 12,910 mi) at 8 knots (15 km/h; 9.2 mph) surfaced
  • 56 nmi (104 km; 64 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth50 m (160 ft)
Complement4 officers, 31 enlisted
Armament
Service record
Part of:
  • IV Flotilla
  • 3 December 1916 – 26 January 1918
Commanders:
  • Kptlt. Walter Roehr[3]
  • 17 October 1916 – 26 January 1918
Operations: 8 patrols
Victories:
  • 28 merchant ships sunk
    (84,906 GRT)
  • 1 warship sunk
    (1,290 tons)
  • 7 merchant ships damaged
    (42,149 GRT)
  • 2 merchant ships taken as prize
    (3,462 GRT)

SM U-84 was one of the 329 submarines serving in the Imperial German Navy (Kaiserliche Marine) in World War I. U-84 was engaged in the naval warfare and took part in the First Battle of the Atlantic.[1]

Initially U-81 to U-83 had one 10.5 cm gun with 140-240 rounds. U-84 - U-86 on the other hand had two 8.8 cm guns. In 1917 U-84 - U-86 were refitted with a single 10.5 cm gun (240 rounds)[1]

Design[edit]

German Type U 81 submarines were preceded by the shorter Type UE I submarines. U-84 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-84 was fitted with four 50 centimetres (20 in) torpedo tubes (two at the bow and two at the 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 1] Fate[4]
14 December 1916 Aamot  Norway 1,362 Captured as prize
18 December 1916 Malcolm  Sweden 2,100 Captured as prize
9 January 1917 Alexandrian  United Kingdom 4,467 Damaged
10 January 1917 Bergenhus  Norway 3,606 Sunk
12 January 1917 Auchencrag  United Kingdom 3,916 Sunk
15 January 1917 Kinpurney  United Kingdom 1,944 Sunk
15 January 1917 Omsk  Denmark 1,574 Sunk
20 January 1917 Bulgarian  United Kingdom 2,515 Sunk
20 January 1917 Neuquen  United Kingdom 3,583 Sunk
17 February 1917 Bayonne  France 2,589 Sunk
17 February 1917 Romsdalen  United Kingdom 2,548 Sunk
18 February 1917 Berrima  United Kingdom 11,137 Damaged
18 February 1917 Hunsworth  United Kingdom 2,991 Damaged
18 February 1917 Juno  Norway 2,416 Sunk
18 February 1917 Valdes  United Kingdom 2,233 Sunk
21 February 1917 Dukat  Norway 1,408 Sunk
22 February 1917 Invercauld  United Kingdom 1,416 Sunk
13 April 1917 Argyll  United Kingdom 3,547 Sunk
13 April 1917 Lime Branch  United Kingdom 5,379 Damaged
18 April 1917 Cragoswald  United Kingdom 3,235 Sunk
18 April 1917 Rowena  United Kingdom 3,017 Sunk
19 April 1917 Elswick Manor  United Kingdom 3,943 Sunk
20 April 1917 Malakand  United Kingdom 7,653 Sunk
1 July 1917 Bachi  Spain 2,184 Sunk
1 July 1917 Demerara  United Kingdom 11,484 Damaged
4 July 1917 Goathland  United Kingdom 3,044 Sunk
7 July 1917 Condesa  United Kingdom 8,557 Sunk
7 July 1917 Oxø  Norway 831 Sunk
12 August 1917 Ursus Minor  Norway 623 Sunk
13 August 1917 HMS Bergamot  Royal Navy 1,290 Sunk
24 November 1917 Actaeon  United States 4,999 Sunk
1 December 1917 Antonios Stathatos  Greece 2,743 Sunk
2 December 1917 Birchgrove  United Kingdom 2,821 Sunk
9 January 1918 Bayvoe  United Kingdom 2,979 Sunk
10 January 1918 Cardiff  United Kingdom 2,808 Damaged
11 January 1918 Mereddio  United Kingdom 3,069 Sunk
12 January 1918 Chateau Laffite  France 1,913 Sunk
17 January 1918 Messidor  United Kingdom 3,883 Damaged

References[edit]

Notes[edit]

  1. ^ Merchant ship tonnages are in gross register tons. Military vessels are listed by tons displacement.

Citations[edit]

  1. ^ a b c Helgason, Guðmundur. "WWI U-boats: U 84". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 25 January 2010.
  2. ^ a b c d e Gröner 1991, pp. 12–14.
  3. ^ Helgason, Guðmundur. "WWI U-boat commanders: Walter Roehr (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 20 January 2015.
  4. ^ Helgason, Guðmundur. "Ships hit by U 84". 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.