SM U-75

For other ships with the same name, see German submarine U-75.

History
German Empire
Name	U-75
Ordered	9 March 1915
Builder	AG Vulkan, Hamburg
Yard number	57
Launched	30 January 1916
Commissioned	26 March 1916
Fate	13 December 1917 - Struck a mine off Terschelling. 23 dead, unknown number of survivors. [1]
General characteristics [2]
Class and type	Type UE I submarine
Displacement	755  t (743 long tons) surfaced 832 t (819 long tons) submerged
Length	56.80 m (186 ft 4 in) (o/a) 46.66 m (153 ft 1 in) (pressure hull)
Beam	5.90 m (19 ft 4 in) (o/a) 5.00 m (16 ft 5 in) (pressure hull)
Height	8.25 m (27 ft 1 in)
Draught	4.86 m (15 ft 11 in)
Installed power	2 × 900  PS (662  kW; 888  shp) surfaced 2 × 800 PS (588 kW; 789 shp) submerged
Propulsion	2 shafts, 2× 1.38 m (4 ft 6 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 depth	50 m (160 ft)
Complement	4 officers, 28 enlisted
Armament	2 × 50 cm (19.7 in) torpedo tubes (one port bow, one starbord stern) 4 torpedoes 1 × 8.8 cm (3.5 in) SK L/30 deck gun
Service record
Part of:	I Flotilla 29 June 1916 – 13 December 1917
Commanders:	Kptlt. Curt Beitzen [3] 26 March 1916 – 1 May 1917 Kptlt. Fritz Schmolling [4] 2 May – 13 December 1917
Operations:	7 patrols
Victories:	8 merchant ships sunk (16,913  GRT) 1 warship sunk (10,850 tons) [1] 3 auxiliary warships sunk (1,434  GRT) 2 merchant ships damaged (7,548  GRT) 1 auxiliary warship damaged (194  GRT) 1 merchant ship taken as prize (1,700  GRT)

SM U-75 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-75 was engaged in naval warfare and took part in the First Battle of the Atlantic. On her first mission, U-75 laid the mine that sank the cruiser HMS Hampshire during her voyage to Russia carrying British Secretary of State for War Lord Kitchener. The cruiser sank at 59°07′N03°24′W / 59.117°N 3.400°W / 59.117; -3.400 west of the Orkney Islands with nearly total loss of life in a force 9 gale.

Design

Type UE I submarines were preceded by the longer Type U 66 submarines. U-75 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 800 metric horsepower (590 kW; 790 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-75 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 cm (3.5 in) SK L/30 deck gun. She had a complement of thirty-two (twenty-eight crew members and four officers). ^[2]

Summary of raiding history

Date	Name	Nationality	Tonnage [Note 1]	Fate [5]
5 June 1916	HMS Hampshire	Royal Navy	10,850	Sunk
22 June 1916	HMD Laurel Crown	Royal Navy	81	Sunk
7 August 1916	HMT John High	Royal Navy	228	Sunk
12 August 1916	Kovda	Imperial Russian Navy	1,125	Sunk
20 September 1916	Etton	United Kingdom	2,831	Sunk
16 November 1916	Fenja	Denmark	433	Sunk
22 November 1916	Reserv	Sweden	1,700	Captured as prize
23 November 1916	Arthur	Sweden	1,435	Sunk
9 April 1917	Ganslei	Russia	1,273	Sunk
15 April 1917	HMT Arctic Prince	Royal Navy	194	Damaged
10 August 1917	Solglimt	Norway	1,037	Sunk
16 August 1917	Palatine	United Kingdom	2,110	Sunk
3 September 1917	Treverbyn	United Kingdom	4,163	Sunk
22 November 1917	King Idwal	United Kingdom	3,631	Sunk
10 December 1917	Aureole	United Kingdom	3,998	Damaged
2 September 1918	Ariadne Christine	United Kingdom	3,550	Damaged

References

Notes

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

Citations

1. Helgason, Guðmundur. "WWI U-boats: U 75". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 18 January 2015.
2. Gröner 1991, pp. 10–11.
3. Helgason, Guðmundur. "WWI U-boat commanders: Curt Beitzen". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 18 January 2015.
4. Helgason, Guðmundur. "WWI U-boat commanders: Fritz Schmolling". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 18 January 2015.
5. Helgason, Guðmundur. "Ships hit by U 75". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 18 January 2015.

Bibliography

• 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.