SM U-89

History
German Empire
Name:	U-89
Ordered:	23 June 1915
Builder:	Kaiserliche Werft Danzig
Yard number:	33
Laid down:	15 December 1915
Launched:	6 October 1916
Commissioned:	21 June 1917
Fate:	Rammed and sunk 12 February 1918
General characteristics [1]
Class and type:	German Type U 87 submarine
Displacement:	757 t (745 long tons) surfaced 998 t (982 long tons) submerged
Length:	65.80 m (215 ft 11 in) (o/a) 50.07 m (164 ft 3 in) (pressure hull)
Beam:	6.20 m (20 ft 4 in) (oa) 4.18 m (13 ft 9 in) (pressure hull)
Height:	9.35 m (30 ft 8 in)
Draught:	3.88 m (12 ft 9 in)
Installed power:	2 × 2,400 PS (1,765 kW; 2,367 shp) surfaced 2 × 1,200 PS (883 kW; 1,184 shp) submerged
Propulsion:	2 shafts, 2 × 1.66 m (5 ft 5 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:	11,380 nmi (21,080 km; 13,100 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 depth:	50 m (164 ft 1 in)
Complement:	4 officers, 32 enlisted
Armament:	4 × 50 cm (19.7 in) torpedo tubes (two bow, two stern) 10-12 torpedoes 1 × 10.5 cm (4.1 in) deck gun 1 × 8.8 cm (3.5 in) deck gun
Service record
Part of:	Imperial German Navy: III Flotilla 6 September 1917 – 12 February 1918
Commanders:	Kptlt. August Mildenberger[2] 21 June 1917 – 15 January 1918 Kptlt. Wilhelm Bauck[3] 16 January – 12 February 1918
Operations:	3 patrols
Victories:	4 merchant ships sunk (8,496 GRT) 1 ship damaged (324 GRT)

SM U-89^{[Note 1]} was one of the 329 submarines serving in the Imperial German Navy in World War I. U-89 was engaged in the naval warfare and took part in the First Battle of the Atlantic.^[4] On 12 February 1918, U-89 was rammed and sunk by HMS Roxburgh off Malin Head. There were no survivors.

Design

German Type U 87 submarines were preceded by the shorter Type U 81 submarines. U-89 had a displacement of 757 tonnes (745 long tons) when at the surface and 998 tonnes (982 long tons) while submerged.^[1] It had a total length of 215 ft 11 in (65.81 m), a pressure hull length of 164 ft 3 in (50.06 m), a beam of 20 ft 4 in (6.20 m), a height of 30 ft 8 in (9.35 m), and a draught of 12 ft 9 in (3.89 m). 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. It had two shafts and two 1.66 m (5.4 ft) propellers. It was capable of operating at depths of up to 50 metres (160 ft).^[1]

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).^[1] When submerged, it could operate for 56 nautical miles (104 km; 64 mi) at 5 knots (9.3 km/h; 5.8 mph); when surfaced, it could travel 11,380 nautical miles (21,080 km; 13,100 mi) at 8 knots (15 km/h; 9.2 mph). U-89 was fitted with four 50 centimetres (20 in) torpedo tubes (two at the bow and two at the stern), ten to twelve torpedoes, one 10.5 centimetres (4.1 in) deck machine gun, and one 8.8 centimetres (3.5 in) deck machine gun. It had a complement of thirty-six (thirty-two crew members and four officers).^[1]

Summary of raiding history

Date	Name	Nationality	Tonnage[Note 2]	Fate[5]
2 October 1917	Trafaria	Portugal	1,744	Sunk
3 October 1917	Baron Blantyre	United Kingdom	1,844	Sunk
6 October 1917	Victorine	France	1,241	Sunk
12 December 1917	Reine D'arvor	France	324	Damaged
21 December 1917	Boa Vista	Portugal	3,667	Sunk

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. Tonnages are in gross register tons

Citations

1. Gröner 1991, pp. 12-14.
2. Helgason, Guðmundur. "WWI U-boat commanders: August Mildenberger". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 21 January 2015.
3. Helgason, Guðmundur. "WWI U-boat commanders: Wilhelm Bauck". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 21 January 2015.
4. Helgason, Guðmundur. "WWI U-boats: U 89". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 25 January 2010.
5. Helgason, Guðmundur. "Ships hit by U 89". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 21 January 2015.

Bibliography

• Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.