German Type II submarine

German Type II submarine
Vesikko, which served as a direct prototype for German Type II
Class overview
Name:	Type II Submarine
Builders:	IIA : Deutsche Werke (6) IIB : Deutsche Werke (4), Germaniawerft (14), Flender Werke (2) IIC : Deutsche Werke (8) IID : Deutsche Werke (16)
Operators:	Kriegsmarine Soviet Navy (post war; U 9, U 18, U 24)
Built:	1934–1940
In commission:	1935–1945
Completed:	IIA : 6 IIB : 20 IIC : 8 IID : 16
General characteristics
Displacement:	IIA : 254 tonnes (250 long tons) surfaced 303 t (298 long tons) submerged 381 t (375 long tons) total IIB : 279 t (275 long tons) surfaced 328 t (323 long tons) submerged 414 t (407 long tons) total IIC : 291 t (286 long tons) surfaced 341 t (336 long tons) submerged 435 t (428 long tons) total IID : 314 t (309 long tons) surfaced 364 t (358 long tons) submerged 460 t (453 long tons) total
Length:	IIA : 40.9 m (134 ft 2 in) o/a 27.8 m (91 ft 2 in) pressure hull IIB : 42.7 m (140 ft 1 in) o/a 28.2 m (92 ft 6 in) pressure hull IIC : 43.9 m (144 ft 0 in) o/a 29.6 m (97 ft 1 in) pressure hull IID : 44 m (144 ft 4 in) o/a 29.8 m (97 ft 9 in) pressure hull
Beam:	IIA, IIB, IIC : 4.1 m (13 ft 5 in) o/a 4 m (13 ft 1 in) pressure hull IID : 4.9 m (16 ft 1 in) o/a 4 m (13 ft 1 in) pressure hull
Height:	IIA, IIB : 8.6 m (28 ft 3 in) IIC, IID : 8.4 m (27 ft 7 in)
Draught:	IIA, IIC : 3.8 m (12 ft 6 in) IIB, IID : 3.9 m (12 ft 10 in)
Propulsion:	All types : 2 × MWM RS127S 6-cylinder diesel engines, 700 hp (522 kW) 2 × SSW PGVV322/26 double-acting electric motors, 402 hp (300 kW)
Speed:	IIA : 13 knots (15 mph; 24 km/h) surfaced 6.9 knots (7.9 mph; 12.8 km/h) submerged IIB : 13 knots (15 mph; 24 km/h) surfaced 7 knots (8.1 mph; 13 km/h) submerged IIC : 12 knots (14 mph; 22 km/h) surfaced 7 knots (8.1 mph; 13 km/h) submerged IID : 12.7 knots (14.6 mph; 23.5 km/h) surfaced 7.4 knots (8.5 mph; 13.7 km/h) submerged
Range:	IIA : 2,500 km (1,300 nmi) at 8 kn (15 km/h) surfaced 55 km (30 nmi) at 4 kn (7.4 km/h) submerged IIB : 5,000 km (2,700 nmi) at 8 kn (15 km/h) surfaced 70 km (38 nmi) at 4 kn (7.4 km/h) submerged IIC : 6,100 km (3,300 nmi) at 8 kn (15 km/h) surfaced 67 km (36 nmi) at 4 kn (7.4 km/h) submerged IID : 9,000 km (4,900 nmi) at 8 kn (15 km/h) surfaced 90 km (49 nmi) at 4 kn (7.4 km/h) submerged
Test depth:	All types : 150 m (490 ft)
Complement:	All types : 22 to 24 men
Armament:	All types : 3 × torpedo tubes (bow), 5 torpedoes

The Type II U-boat was designed by Germany as a coastal U-boat, modeled after the CV-707 submarine, which was designed by the Dutch dummy company NV Ingenieurskantoor voor Scheepsbouw den Haag (I.v.S) (set up by Germany after World War I in order to maintain and develop German submarine technology and to circumvent the limitations set by the Treaty of Versailles) and built in 1933 by the Finnish Crichton-Vulcan shipyard in Turku, Finland. It was too small to undertake sustained operations far away from the home support facilities. Its primary role was found to be in the training schools, preparing new German naval officers for command. It appeared in four sub-types.

Background

Germany was stripped of her U-boats by the Treaty of Versailles at the end of World War I, but in the late 1920s and early 1930s began to rebuild her armed forces. The pace of rearmament accelerated under Adolf Hitler, and the first Type II U-boat was laid down on 11 February 1935. Knowing that the world would see this step towards rearmament, Hitler reached an agreement with Britain to build a navy up to 35% of the size of the Royal Navy in surface vessels, but equal to the British in number of submarines. This agreement was signed on 18 June 1935, and U-1 was commissioned 11 days later.

Design

The defining characteristic of the Type II was its tiny size. Known as the Einbaum ("dugout canoe"), it had the advantages over larger boats of the ability to work in shallow water, diving more quickly, and being more difficult to spot due to the low conning tower. However, it had a shallower maximum depth, short range, and cramped living conditions, and could carry few torpedoes.

The boat had a single hull, with no watertight compartments. There were three torpedo tubes forward (none aft), with space for another two torpedoes inside the pressure hull for reloads. A single 20 mm anti-aircraft gun was provided, but no deck gun was mounted.

Space inside was limited. The two spare torpedoes extended from just behind the torpedo tubes to just in front of the control room, and most of the 24-man crew lived in this forward area around the torpedoes, sharing 12 bunks. Four bunks were also provided aft of the engines for the engine room crew. Cooking and sanitary facilities were basic, and in this environment long patrols were very arduous.

Most Type IIs only saw operational service during the early years of the war, thereafter remaining in training bases. Six were stripped down to just a hull, transported by river and truck to Linz (on the Danube), and reassembled for use in the Black Sea against the Soviet Union.

In contrast to other German submarine types, few Type IIs were lost. This, of course, reflects their use as training boats, although accidents accounted for several vessels.

These boats were a first step towards re-armament, intended to provide Germany with experience in submarine construction and operation and lay the foundation for larger boats to build upon. Only one of these submarines survives to this day; the prototype CV-707, renamed Vesikko by the Finnish Navy which later bought it.

On February 3, 2008, The Telegraph reported that U-20 had been discovered by Selçuk Kolay, a Turkish marine engineer in 80 feet (24 m) of water off the coast of the Turkish city of Zonguldak. [1] The paper also reported that Kolay knows where U-23 and U-19 are, scuttled in deeper water near U-20.

Comparison of Finnish Crichton-Vulcan CV-707(U2A) to German Type II

	CV-707	Type IIA U1-U6
Launched	10 May 1933	1934–1935
Displacement (tonnes)
Surfaced	254	254
Submerged	303	303
Total	381	381
Size (metres)
Length	40.9	40.9
Beam	4.1	4.1
Draft	4.2	3.8
Speed (knots)
Surfaced	13	13
Submerged	8	6.9
Range (nautical miles)
Surfaced	1,350 nmi (2,500 km) at 8 knots (15 km/h)	1,000 nmi (1,900 km) at 8 knots (15 km/h)
Submerged	40 nmi (74 km) at 4 knots (7.4 km/h)	35 nmi (65 km) at 4 knots (7.4 km/h)
Engine	Diesel-electric	Diesel-electric
	2 × MWM Diesel 700 hp (520 kW)	2 × MWM Diesel 700 hp (520 kW)
	2 × Siemens Electric 360 hp (270 kW)	2 × Siemens Electric 402 hp (300 kW)

Type IIA

Deutsche Werke AG, of Kiel built six Type IIAs in 1934 and 1935.

List of Type IIA submarines

U-1 U-2 U-3

U-4 U-5 U-6

Type IIB

Deutsche Werke AG, of Kiel, built four Type IIBs in 1935 and 1936, Germaniawerft AG, of Kiel, built fourteen in 1935 and 1936, and Flender Werke AG, of Lübeck, built two between 1938 and 1940, for a total of twenty built.

List of Type IIB submarines

There were 20 Type IIB submarines commissioned.

U-7 U-8 U-9 U-10 U-11

U-12 U-13 U-14 U-15 U-16

U-17 U-18 U-19 U-20 U-21

U-22 U-23 U-24 U-120 U-121

Type IIC

Deutsche Werke AG, of Kiel built eight Type IICs between 1937 and 1940.

List of Type IIC submarines

There were eight Type IIC submarines commissioned

U-56 U-57 U-58 U-59

U-60 U-61 U-62 U-63

Type IID

Deutsche Werke AG, of Kiel built sixteen Type IIDs in 1939 and 1940.

List of Type IID submarines

There were 16 Type IID submarines commissioned

U-137 U-138 U-139 U-140

U-141 U-142 U-143 U-144

U-145 U-146 U-147 U-148

U-149 U-150 U-151 U-152

Ships in class

See list of German Type II submarines for individual ship details

See also

• List of naval ship classes of Germany
• List of World War II ship classes
• Ingenieurskantoor voor Scheepsbouw

References

• Dutch Export Submarines - Ingenieurskantoor voor Scheepsbouw