NAVYPEDIA

Photo

U20 Many thanks to Wolfgang Stöhr for additional information on this page.

Ships

Name	No	Yard No	Builder	Laid down	Launched	Comp	Fate
U20			UBAG // Marinearsenal Pola	9/1915	18.9.1916	3/1917	sunk 5.7.1918
U21		570	UBAG-Linz // Whitehead, Fiume	10/1915	15.8.1916	11/1916	to Italy 1920
U22		571	UBAG-Linz // Whitehead, Fiume	12/1915	27.1.1917	6/1917	to France 1920
U23			UBAG // Marinearsenal Pola	12/1915	5.1.1917	6/1917	sunk 21.2.1918

Technical data

Displacement standard, t
Displacement normal, t	173 / 210
Length, m	38.8
Breadth, m	3.97
Draught, m	2.75
No of shafts	1
Machinery	1 diesel / 1 electric motor
Power, h. p.	450 / 300
Max speed, kts	12 / 9
Fuel, t	diesel oil
Endurance, nm(kts)	2000(7) / 54(4)
Armament	U20 - 22: 1 x 1 - 66/24 G. L/26 K.15 BAK, 2 - 450 TT (bow, 2) U23: 1 x 1 - 47/40 SFK L/44 S, 2 - 450 TT (bow, 2)
Complement	18
Diving depth operational, m	50?

Standard scale images

Graphics

Project history

Between 1911 and 1912 the Royal Danish Navy ordered 3 single-hulled Havmanden class (A type) boats from Whitehead's Fiume yard, and the Austro-Hungarian Navy seized the plans after the outbreak of war and ordered 4 boats on 27 March 1915. Following the pattern of the Dual Monarchy, construction was divided between the Austrian Pola N Yd (U20 and U21) and the Hungarian UBAG yard. The subcontracts were also divided up, which led to a lot of technical troubles, later modifications and modernizations during construction, finally resulting in an unfortunate and long-delayed type. They were not commissioned until the end of 1917 and operated without success.

Modernizations

None.

Naval service

U23 was sunk on 21 February 1918 with an explosive paravane, when she attacked a convoy in the Otranto straits. U20 was torpedoed by the Italian submariner F12 off the Tagliamento estuary; raised in 1962 she was scrapped. The CT plus a small midships section of this boat is now exhibited in the Heeresgeschichtliches Museum in Vienna. U21 was ceded to Italy in 1920, U22 to France, and both were scrapped.

Many thanks to Wolfgang Stöhr for additional information on this page.