SM U-23 (Germany)

History
German Empire
Name:	U-23
Ordered:	18 March 1911
Builder:	Friedrich Krupp Germaniawerft, Kiel
Cost:	2,808,000 Goldmark
Yard number:	177
Laid down:	21 December 1911
Launched:	12 April 1912
Commissioned:	11 September 1913
Fate:	20 July 1915 - torpedoed and sunk by HMS C27
General characteristics Ocean-going diesel submarine
Class and type:	German Type U 23 submarine
Displacement:	669 t (658 long tons) surfaced 864 t (850 long tons) submerged
Length:	64.70 m (212.3 ft)
Beam:	6.32 m (20 ft 9 in)
Draught:	3.45 m (11 ft 4 in)
Propulsion:	2 shafts 2 × Germania 6-cylinder two stroke diesel motors with 1,800 PS (1,800 hp) 2 × SSW double Motordynamos with 1,200 PS (1,200 hp) 450rpm surfaced 330 rpm submerged
Speed:	16.7 knots (30.9 km/h; 19.2 mph) surfaced 10.3 knots (19.1 km/h; 11.9 mph) submerged
Range:	9,910 nmi (18,350 km; 11,400 mi) at 8 knots (15 km/h; 9.2 mph) surfaced 85 nmi (157 km; 98 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth:	about 50 m (160 ft)
Boats & landing craft carried:	1 dingi
Complement:	4 officers, 31 men
Armament:	4 × 50 cm (19.7 in) torpedo tubes (2 each bow and stern) 6 torpedoes 1 × 8.8 cm (3.5 in) SK L/30 gun
Service record
Part of:	Imperial German Navy IV Flotilla 1 August 1914 - unknown end III Flotilla unknown start – 20 July 1915
Commanders:	Kptlt. Erwin Weisbach[1] 1 August – 25 November 1914 Kptlt. Hans Adam[2] 26 November – 17 December 1914 Kptlt. Egewolf Freiherr von Berckheim[3] 18 December 1914 – 12 January 1915 Kptlt. Hans Schultheß[4] 13 January – 20 July 1915
Operations:	3 patrols
Victories:	7 ships sunk (8,822 GRT)

SM U-23 was one of the 329 U-boats serving in the Imperial German Navy in World War I. U-23 was engaged in the naval warfare and took part in the First Battle of the Atlantic.

U-23 served on 3 war patrols, sinking a total of 7 ships for 8,822 tons. She was baited by the Q ship Princess Louise and torpedoed by HMS C27 at 58°55′N 0°14′E / 58.917°N 0.233°ECoordinates: 58°55′N 0°14′E / 58.917°N 0.233°E, between the Orkney and Shetland Islands off Fair Isle. Twenty four men died and 10 survived.

Summary of raiding history

Date	Name	Nationality	Tonnage (GRT)	Fate[5]
13 May 1915	Invergyle	United Kingdom	1,794	Sunk
15 May 1915	Fingal	United Kingdom	1,562	Sunk
15 May 1915	Martha	Denmark	1,182	Sunk
19 May 1915	Chrysolite	United Kingdom	222	Sunk
19 May 1915	Crimond	United Kingdom	173	Sunk
19 May 1915	Lucerne	United Kingdom	154	Sunk
22 May 1915	Minerva	Norway	3,735	Sunk

References

1. Helgason, Guðmundur. "WWI U-boat commanders: Erwin Weisbach". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 March 2015.
2. Helgason, Guðmundur. "WWI U-boat commanders: Hans Adam (Pour le Mérite)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 March 2015.
3. Helgason, Guðmundur. "WWI U-boat commanders: Egewolf Freiherr von Berckheim (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 March 2015.
4. Helgason, Guðmundur. "WWI U-boat commanders: Hans Schultheß". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 March 2015.
5. Helgason, Guðmundur. "Ships hit by U 23". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 March 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.