NAVYPEDIA

Photo

U4 1909 Many thanks to Wolfgang Stöhr for additional information on this page.

Ships

Name	No	Yard No	Builder	Laid down	Launched	Comp	Fate
U3		135	Germaniawerft, Kiel, Germany	3/1907	20.8.1908	9/1909	sunk 13.8.1915
U4		136	Germaniawerft, Kiel, Germany	3/1907	20.11.1908	8/1909	to France 1920

Technical data

Displacement normal, t	240 / 300
Displacement full, t
Length, m	42.3 wl 43.2 oa
Breadth, m	3.65
Draught, m	2.80
No of shafts	2
Machinery	2 Körting kerosene engines / 2 electric motors
Power, h. p.	600 / 340
Max speed, kts	12 / 8.5
Fuel, t	kerosene
Endurance, nm(kts)	1200(6) / 45(3)
Armament	2 - 450 TT (bow, 3)
Complement	21
Diving depth operational, m	30

Standard scale images

Graphics

Project history

Built by Germaniawerft at Kiel and towed to Pola via Gibraltar, they were of a double-hull type with internal saddle tanks. Although the German designers had evaluated the best hull-shaped in extensive model trials, these boats had constant troubles with their diving planes. The fins were changed in size and shape, and finally the bow planes were removed and a fixed stern flap was installed. Because of their greater displacement these boats had better seakeeping qualities and living conditions than their competitors. Considering that this was one of the first Germaniawerft designs, produced without extensive practical experience, these boats showed a high degree of effectiveness, and U4 had the longest operational history of all Austrian submarines.

Modernizations 4.

1915, U4: + 1 x 1 - 37/20 SFK L/23 H

1917, U4: - 1 x 1 - 37/20; + 1 x 1 - 66/24 G. L/26 K.15 BAK

Naval service

Both saw action during the war. U3 made an unsuccessful attack on the Italian armed merchant cruiser Città di Catania, was rammed and damaged, and when surfacing was hit by the French destroyer Bisson and sunk 13.8.1915. U4 was ceded as a war reparation to France and scrapped in 1920.

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