Military Wiki
German Type X submarine
U-234 surrenders to USS Sutton
U-234 surrenders to USS Sutton, 1945
Class overview
Builders: Friedrich Krupp Germaniawerft, Kiel
Operators:  Kriegsmarine
 Imperial Japanese Navy
Built: 1939–1944
In commission: 1941–1945
Completed: 8
Lost: 6
General characteristics [1]
Type: Submarine minelayer
Displacement: 1,763 long tons (1,791 t) surfaced
2,177 long tons (2,212 t) submerged
Length: 89.80 m (294 ft 7 in) o/a
70.90 m (232 ft 7 in) pressure hull
Beam: 9.20 m (30 ft 2 in) o/a
4.75 m (15 ft 7 in) pressure hull
Height: 10.20 m (33 ft 6 in)
Draught: 4.71 m (15 ft 5 in)
Propulsion: 2 × diesel engines, 4,800 hp (3,600 kW)
2 × electric motors, 1,100 hp (820 kW)
Speed: 17 knots (31 km/h; 20 mph) surfaced
7 knots (13 km/h; 8.1 mph) submerged
Range: 18,450 nmi (34,170 km) at 10 kn (19 km/h) surfaced
93 nmi (172 km) at 4 kn (7.4 km/h) submerged
Test depth: Calculated crush depth: 220 m (720 ft)
Complement: 48-60 men
Armament: • 2 × 53.3 cm (21 in) stern torpedo tubes
• 15 × torpedoes
• 66 × SMA mines
• 1 × 10.5 cm SK C/32 naval gun[2] (200 rounds)

Type X (XB) U-boats were a special type of German submarine (U-boat). Although intended as long-range mine-layers, they were later used as long-range cargo transports, a task they shared with the Type IXD and Italian Romolo-class submarines.


The Type X was originally designed specifically to accommodate the newly developed Schachtmine A (SMA) moored mine. The initial design provided dry storage for the mines, which needed their detonators to be individually adjusted before launch; this submarine was projected to have displaced up to 2,500 tons. A further variant, the Type XA was projected, which would have supplemented the main mine chamber with extra mine shafts in the saddle tanks. Neither type entered production.[3]

A total of eight Type XB boats were produced, which replaced the mine chamber of the projected Type XA with six vertical wet storage shafts in the forward section of the hull. Up to 18 mines could be carried in these shafts, with an additional 48 mines in a series of 12 shafts set into the saddle tanks on each side. They only had two torpedo tubes, both at the stern. When used as cargo-carrying submarines they carried freight containers in the mine shafts (or had the freight containers welded on top of the lateral shafts, preventing their use for mines).

The first Type XB was launched in May 1941. At 2,710 tons submerged and fully loaded, they were the largest German U-boats ever built, and they had to sacrifice diving speed and agility.

Service history

Six of the eight boats built were sunk during the war (five with all hands) but two survived the war. One survivor was U-234, which surrendered to US Navy ships on 14 May 1945 while en route for Japan with a cargo that included 560 kg uranium oxide, two Me 262 jet fighters, and 10 jet engines.

The other type XB to survive was U-219 which reached Djakarta in December 1944 with a cargo including dismantled V-2 rockets for Japan. Following Germany's surrender, U-219 was seized by the Japanese at Batavia on 8 May 1945 and on 15 July 1945 was placed into service with the Imperial Japanese Navy as I-505.

List of Type X submarines

There were eight Type X submarines commissioned.


Six Type XBs were lost to various causes.

See also


  1. "Type XB Mine-laying boats - German U-boat Types of WWII -". Retrieved 2009-12-20. 
  2. Campbell, John Naval Weapons of World War Two ISBN 0-87021-459-4 pp.248&249
  3. Williamson, p. 53


  • Williamson, Gordon; Ian Palmer (2002). Kriegsmarine U-boats 1939-45: Vol 2. Osprey Publishing. ISBN 1-84176-364-0. 

External links

This page uses Creative Commons Licensed content from Wikipedia (view authors).