SM U-77[Note 1] was one of 329 submarines serving in the Imperial German Navy in World War I, engaged in commerce warfare during the First Battle of the Atlantic.

History
German Empire
NameU-77
Ordered9 March 1915
BuilderAG Vulkan, Hamburg
Yard number59
Launched9 January 1916
Commissioned10 March 1916
FateMissing since 7 July 1916 during a minelaying mission off Kinnaird Head, Scotland. 33 dead (all hands lost).[1]
General characteristics [2]
Class and typeType UE I submarine
Displacement
  • 755 t (743 long tons) surfaced
  • 832 t (819 long tons) submerged
Length
Beam
  • 5.90 m (19 ft 4 in) (o/a)
  • 5.00 m (16 ft 5 in) (pressure hull)
Height8.25 m (27 ft 1 in)
Draught4.86 m (15 ft 11 in)
Installed power
  • 2 × 900 PS (662 kW; 888 shp) surfaced
  • 2 × 800 PS (588 kW; 789 shp) submerged
Propulsion2 shafts, 2× 1.41 m (4 ft 8 in) propellers
Speed
  • 9.9 knots (18.3 km/h; 11.4 mph) surfaced
  • 7.9 knots (14.6 km/h; 9.1 mph) submerged
Range
  • 7,880 nmi (14,590 km; 9,070 mi) at 7 knots (13 km/h; 8.1 mph) surfaced
  • 83 nmi (154 km; 96 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth50 m (164 ft 1 in)
Complement4 officers, 28 enlisted
Armament
Service record
Part of:
  • I Flotilla
  • 29 June – 7 July 1916
Commanders:
  • Kptlt. Erich Günzel[3]
  • 10 March – 7 July 1916
Operations: 2 patrols
Victories: No ships sunk or damaged[1]

Design

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Type UE I submarines were preceded by the longer Type U 66 submarines. U-77 had a displacement of 755 tonnes (743 long tons) when at the surface and 832 tonnes (819 long tons) while submerged.[2] She had a total length of 56.80 m (186 ft 4 in), a pressure hull length of 46.66 m (153 ft 1 in), a beam of 5.90 m (19 ft 4 in), a height of 8.25 m (27 ft 1 in), and a draught of 4.86 m (15 ft 11 in). The submarine was powered by two 900 metric horsepower (660 kW; 890 shp) engines for use while surfaced, and two 900 metric horsepower (660 kW; 890 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 9.9 knots (18.3 km/h; 11.4 mph) and a maximum submerged speed of 7.9 knots (14.6 km/h; 9.1 mph).[2] When submerged, she could operate for 83 nautical miles (154 km; 96 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 7,880 nautical miles (14,590 km; 9,070 mi) at 7 knots (13 km/h; 8.1 mph). U-77 was fitted with two 50 centimetres (20 in) torpedo tubes (one at the port bow and one starboard stern), four torpedoes, and one 8.8 centimetres (3.46 in) deck gun. She had a complement of thirty-two (twenty-eight crew members and four officers).[2]

Operations

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U-77 was commanded by Kaptlt Erich Günzel, who was lost with her. She came off the stocks at Hamburg (Vulcan) in 1916; in May and June was at Kiel School, and first entered North Sea with U-76 on 29 June, to join the 1st Half Flotilla.[4]

Previously recorded fate

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U-77 was thought to have sunk off Dunbar, Scotland in May 1916 as a result of a mine handling accident. The submarine involved was actually U-74.[5]

References

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Notes

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  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.

Citations

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  1. ^ a b Helgason, Guðmundur. "WWI U-boats: U 77". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 18 January 2015.
  2. ^ a b c d e Gröner 1991, pp. 10–11.
  3. ^ Helgason, Guðmundur. "WWI U-boat commanders: Erich Günzel". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 18 January 2015.
  4. ^ HW 7/3, Room 40, History of German Naval Warfare 1914-1918. National Archives, Kew.
  5. ^ "War Patrols By German U-Boat 74". uboat.net. Retrieved 25 May 2024.

Bibliography

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  • 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.