SM UB-103

For other ships with the same name, see German submarine U-103.

SM UB-103 was a German Type UB III submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. She was commissioned on 18 December 1917 as SM UB-103.^{[Note 1]}

UB-148 at sea, a U-boat similar to UB-103.
History
German Empire
Name	UB-103
Ordered	6 / 8 February 1917[1]
Builder	Blohm & Voss, Hamburg
Cost	3,714,000 German Papiermark
Yard number	309
Launched	7 July 1917[2]
Commissioned	18 December 1917[2]
Fate	Sunk 14 August 1918[2]
General characteristics [2]
Class & type	Type UB III submarine
Displacement	510 t (500 long tons) surfaced 629 t (619 long tons) submerged
Length	55.30 m (181 ft 5 in) (o/a)
Beam	5.80 m (19 ft)
Draught	3.70 m (12 ft 2 in)
Propulsion	2 × propeller shaft 2 × MAN-Vulcan four-stroke 6-cylinder diesel engines, 1,085 bhp (809 kW) 2 × Siemens-Schuckert electric motors, 780 shp (580 kW)
Speed	13.3 knots (24.6 km/h; 15.3 mph) surfaced 7.5 knots (13.9 km/h; 8.6 mph) submerged
Range	7,420 nmi (13,740 km; 8,540 mi) at 6 knots (11 km/h; 6.9 mph) surfaced 55 nmi (102 km; 63 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth	50 m (160 ft)
Complement	3 officers, 31 men
Armament	5 × 50 cm (19.7 in) torpedo tubes (4 bow, 1 stern) 10 torpedoes 1 × 8.8 cm (3.46 in) deck gun
Service record
Part of:	Flandern I Flotilla 8 March – 14 August 1918
Commanders:	Kptlt. Paul Hundius[3] 18 December 1917 – 14 August 1918
Operations:	6 patrols
Victories:	15 merchant ships sunk (25,999 GRT)

UB-103 was sunk in the English Channel at 50°52′N 1°27′E by British warships and SSZ 1, a SSZ class airship.^[2] All hands were lost.^[4]

Construction

Main article: Type UB III submarine

She was built by Blohm & Voss of Hamburg and, after just under a year of construction, launched at Hamburg on 7 July 1917. UB-103 was commissioned later the same year, under the command of KptLt Paul Hundius. Like all Type UB III submarines, UB-103 carried 10 torpedoes and was armed with a 8.8 cm (3.46 in) deck gun. UB-103 had a crew of up to three officers and 31 men, and its cruising range was 7,420 nautical miles (13,740 km; 8,540 mi). UB-103 had a displacement of 510 t (500 long tons) while surfaced and 629 t (619 long tons) when submerged. Her engines enabled her to travel at 13.3 knots (24.6 km/h; 15.3 mph) when surfaced and 7.4 knots (13.7 km/h; 8.5 mph) when submerged.

Summary of raiding history

Date	Name	Nationality	Tonnage[Note 2]	Fate[5]
20 March 1918	Eros	Sweden	858	Sunk
21 March 1918	Tyrhaug	United Kingdom	1,483	Sunk
24 March 1918	Anteros	United Kingdom	4,241	Sunk
22 April 1918	Eric Calvert	United Kingdom	1,862	Sunk
28 April 1918	Elba	United Kingdom	1,081	Sunk
2 May 1918	Thorsa	United Kingdom	1,319	Sunk
3 May 1918	Vasilefs Georgios	Greece	3,651	Sunk
10 June 1918	Borg	United Kingdom	2,111	Sunk
11 June 1918	Lorle	United Kingdom	2,686	Sunk
12 June 1918	Kul	United Kingdom	1,095	Sunk
11 July 1918	Kong Guttorm	Norway	731	Sunk
15 July 1918	Cap Breton	France	1,464	Sunk
15 July 1918	Vendee	France	892	Sunk
16 July 1918	Lyndiane	France	1,564	Sunk
21 July 1918	Arvor	France	961	Sunk