SM UB-109

	UB-148 at sea, a U-boat similar to UB-109.
History
German Empire
Name	UB-109
Ordered	6 / 8 February 1917
Builder	Blohm & Voss, Hamburg
Cost	3,714,000 German Papiermark
Yard number	315
Launched	7 July 1917
Commissioned	31 December 1917
Fate	Sunk by mine on 29 August 1918 at 51°3′N 1°44′E / 51.050°N 1.733°E
General characteristics
Class and 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 × Maffei 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; 30 March – 29 August 1918;
Commanders:	Oblt.z.S. / Kptlt. Kurt Ramien; 31 December 1917 – 29 August 1918;
Operations:	3 patrols
Victories:	7 merchant ships sunk ; (14,092 GRT)

SM UB-109 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 into the German Imperial Navy on 31 December 1917 as SM UB-109.^{[Note 1]}

UB-109 was sunk by mine in the English Channel on 29 August 1918^[2] and underwater scanning of the area covered by the Dover Barrage shows her wreck broken in half.^[4]

Construction

She was built by Blohm & Voss of Hamburg and following just under a year of construction, launched at Hamburg on 7 July 1917. UB-109 was commissioned later the same year under the command of Oblt.z.S. Kurt Ramien. Like all Type UB III submarines, UB-109 carried 10 torpedoes and was armed with a 8.8 cm (3.46 in) deck gun. UB-109 would carry a crew of up to 3 officer and 31 men and had a cruising range of 7,420 nautical miles (13,740 km; 8,540 mi). UB-109 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]
9 April 1918	President Leroy-lallier	France	1,320	Sunk
10 April 1918	Henley	United Kingdom	3,249	Sunk
13 April 1918	Wilson	United Kingdom	110	Sunk
18 April 1918	Runswick	United Kingdom	3,060	Sunk
19 August 1918	Zinal	United Kingdom	4,037	Sunk
25 August 1918	Pontet Canet	France	1,183	Sunk
26 August 1918	Helge	Sweden	1,133	Sunk

References

Notes

^ "SM" stands for "Seiner Majestät" (English: His Majesty's) and combined with the U for Unterseeboot would be translated as His Majesty's Submarine.
^ Tonnages are in gross register tons

Citations

^ Rössler 1979, p. 66.
^ ^a ^b ^c ^d ^e ^f Gröner 1991, pp. 25–30.
^ Helgason, Guðmundur. "WWI U-boat commanders: Kurt Ramien (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 9 March 2015.
^ "The Maritime Archaeology of the Dover Barrage". Wessex archaeology on line. Retrieved 1 September 2015.
^ Helgason, Guðmundur. "Ships hit by UB 109". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 9 March 2015.

Bibliography

Bendert, Harald (2000). Die UB-Boote der Kaiserlichen Marine, 1914-1918. Einsätze, Erfolge, Schicksal (in German). Hamburg: Verlag E.S. Mittler & Sohn GmbH. ISBN 3-8132-0713-7.
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.
Rössler, Eberhard (1979). Die deutschen U-Boote und ihre Werften: eine Bilddokumentation über den deutschen U-Bootbau; in zwei Bänden (in German). Vol. I. Munich: Bernard & Graefe. ISBN 3-7637-5213-7.

External links

[4] "SM" stands for "Seiner Majestät" (English: His Majesty's) and combined with the U for Unterseeboot would be translated as His Majesty's Submarine.

[tonnage-6] Tonnages are in gross register tons

[FOOTNOTERössler197966-1] Rössler 1979, p. 66.

[FOOTNOTEGröner199125–30-2] ^ ^a ^b ^c ^d ^e ^f Gröner 1991, pp. 25–30.

[3] Helgason, Guðmundur. "WWI U-boat commanders: Kurt Ramien (Royal House Order of Hohenzollern)". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 9 March 2015.

[5] "The Maritime Archaeology of the Dover Barrage". Wessex archaeology on line. Retrieved 1 September 2015.

[7] Helgason, Guðmundur. "Ships hit by UB 109". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 9 March 2015.

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[Note 1]

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[Note 2]

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v t e Type UB III submarines
SM UB-48 SM UB-49 SM UB-50 SM UB-51 SM UB-52 SM UB-53 SM UB-54 SM UB-55 SM UB-56 SM UB-57 SM UB-58 SM UB-59 SM UB-60 SM UB-61 SM UB-62 SM UB-63 SM UB-64 SM UB-65 SM UB-66 SM UB-67 SM UB-68 SM UB-69 SM UB-70 SM UB-71 SM UB-72 SM UB-73 SM UB-74 SM UB-75 SM UB-76 SM UB-77 SM UB-78 SM UB-79 SM UB-80 SM UB-81 SM UB-82 SM UB-83 SM UB-84 SM UB-85 SM UB-86 SM UB-87 SM UB-88 SM UB-89 SM UB-90 SM UB-91 SM UB-92 SM UB-93 SM UB-94 SM UB-95 SM UB-96 SM UB-97 SM UB-98 SM UB-99 SM UB-100 SM UB-101 SM UB-102 SM UB-103 SM UB-104 SM UB-105 SM UB-106 SM UB-107 SM UB-108 SM UB-109 SM UB-110 SM UB-111 SM UB-112 SM UB-113 SM UB-114 SM UB-115 SM UB-116 SM UB-117 SM UB-118 SM UB-119 SM UB-120 SM UB-121 SM UB-122 SM UB-123 SM UB-124 SM UB-125 SM UB-126 SM UB-127 SM UB-128 SM UB-129 SM UB-130 SM UB-131 SM UB-132 SM UB-133 SM UB-136 SM UB-142 SM UB-143 SM UB-144 SM UB-145 SM UB-148 SM UB-149 SM UB-150 SM UB-154 SM UB-155
Preceded by: Type UB II Followed by: Type VII (World War II)
List of U-boats of Germany

v t e Shipwrecks and maritime incidents in August 1918
Shipwrecks	2 Aug: HMS Ariel, Floréal, HMS Vehement 3 Aug: SM UB-53, HMAT Warilda 6 Aug: HMS Comet, Diamond Shoal Lightship No. 71 7 Aug: Dupetit-Thouars 8 Aug: SM UC-49 10 Aug: Polynesien 13 Aug: Etruria, SM UB-30 14 Aug: SM UB-57, SM UB-103 15 Aug: HMS Scott 18 Aug: USAT Montanan 22 Aug: SS Prunelle 27 Aug: Pampa, USS SC-209 28 Aug: SM UC-70 29 Aug: SM UB-109 Unknown date: SM UB-12
Other incidents	7 Aug: USS O-6, USS Paul Jones 25 Aug: USS Sappho 27 Aug: Felix Taussig 30 Aug: HMS Endymion
1917 1918 1919 July 1918 September 1918