Type UB III submarine

UB-86 washed ashore 1921
Class overview
Builders	AG Weser, Bremen Blohm & Voss, Hamburg AG Vulcan, Hamburg Germaniawerft, Kiel
Operators	Imperial German Navy  Imperial Japanese Navy  French Navy
Preceded by	UB II
Built	1916–1918
In commission	1917–1935
Planned	201
Building	145
Completed	96
Cancelled	56
Lost	37
General characteristics
Type	Coastal submarine
Displacement	508–555 t (500–546 long tons) surfaced 629–684 t (619–673 long tons) submerged
Length	55.30–57.80 m (181 ft 5 in – 189 ft 8 in) (o/a) 40.10 m (131 ft 7 in) (pressure hull)
Beam	5.76–5.80 m (18 ft 11 in – 19 ft 0 in)
Draught	3.67–3.85 m (12 ft 0 in – 12 ft 8 in)
Installed power	6-cylinder diesel engines, 1,060–1,100 PS (780–809 kW; 1,045–1,085 shp) electric motors, 788 PS (580 kW; 777 shp)
Propulsion	2 shafts, 2 1.40 m (4 ft 7 in) propellers
Speed	13.2–13.9 knots (24.4–25.7 km/h; 15.2–16.0 mph) surfaced 7.4–8 knots (13.7–14.8 km/h; 8.5–9.2 mph) submerged
Range	7,120–9,090 nmi (13,190–16,830 km; 8,190–10,460 mi) at 6 knots (11 km/h; 6.9 mph) surfaced 50–55 nmi (93–102 km; 58–63 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth	50 m (160 ft)
Complement	3 officers, 31 men
Armament	4 × 50 cm (19.7 in) bow torpedo tubes 1 × stern tube 10 torpedoes 1 × 8.8 cm (3.5 in) SK L/30 or 10.5 cm (4.1 in) SK L/45 deck gun

The Type UB III submarine was a class of U-boat built during World War I by the German Imperial Navy.

UB III boats carried 10 torpedoes and were usually armed with either an 8.8 cm (3.5 in) or a 10.5 cm (4.1 in) deck gun. They carried a crew of 34 and had a cruising range of 7,120–9,090 nautical miles (13,190–16,830 km; 8,190–10,460 mi). Between 1916 and 1918, 96 were built.^[1]

The UB III type was a coastal submarine, and being a submersible torpedo boat was less akin to UB II type "attack" (i.e. torpedo-launching) boats that preceded it than the highly successful UC II type minelaying submarine. The UC IIs had gained their reputation by sinking more than 1,800 Allied and neutral vessels.^[2] German engineers did not miss the chance of expanding the potential of this capable design by incorporating some of its features into a new submersible torpedo boat.

The UB IIIs joined the conflict mid-1917, after the United States declared war on Germany and the United States Navy was added to the ranks of their enemies. When the convoy system was introduced, it became more difficult to engage enemy merchant shipping without being spotted by destroyer escorts.^[3] Nevertheless, the UB IIIs performed their duties with distinction, sinking 521 ships with a total of 1,123,211 gross register tons (GRT) and 7 warships, including the battleship HMS Britannia, before the end of hostilities.

More than 200 UB III boats were ordered. Of these, 96 were completed, and 89 commissioned into the German Imperial Navy. Thirty-seven boats were lost, four in accidents.^[4] Surviving boats had to be surrendered to the Allies in accordance with the requirements of the Armistice with Germany, some of these boats served until 1935.^[1]

Germany was prohibited from acquiring a new submarine force by the Treaty of Versailles, but German admirals had no intention of allowing their nation to forget how to construct submarines. Germany started to manufacture and to export slightly modified versions of UB IIs and UB IIIs. Having kept the skills of their engineers polished by this means, they eventually ordered the construction of a new coastal submarine. The resulting design was an improved UB-III that had the benefit of new, all-welded construction techniques and an array of electronic and electromechanical gadgets: the Type VII submarine, the most common U-boat of the Kriegsmarine, was born.^[5]

There were 96 Type UB III submarines commissioned into the German Imperial Navy.

• Conway's All the World's Fighting Ships 1906–1921
• 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 (2001). The U-boat: The evolution and technical history of German submarines. London: Cassell & Co. ISBN 0-304-36120-8.