Type 201 submarine

Class overview
Builders:	Howaldtswerke, Kiel, Germany
Operators:	German Navy
Succeeded by:	Type 205 submarine
Planned:	12
Completed:	3
Cancelled:	9
Active:	0
Retired:	3
General characteristics
Type:	Type 201 U-boat
Displacement:	395 t (389 long tons) surfaced 433 t (426 long tons) submerged
Length:	42.40 m (139 ft 1 in)
Beam:	4.60 m (15 ft 1 in)
Draft:	3.80 m (12 ft 6 in)
Propulsion:	880 kilowatts (1,180 hp) diesel generator; 1,100 kilowatts (1,500 hp) electric motor
Speed:	10.7 knots (19.8 km/h; 12.3 mph), surfaced; 17.5 knots (32.4 km/h; 20.1 mph), submerged
Range:	3,800 nautical miles (7,000 km; 4,400 mi), surfaced; 270 nautical miles (500 km; 310 mi) at 3 knots (5.6 km/h; 3.5 mph), submerged
Test depth:	100 metres (330 ft)
Complement:	21
Sensors and processing systems:	sonar, radar, periscope, GHG
Armament:	8 × 533 millimetres (21.0 in) torpedo tubes, 8 torpedoes (no reloads) or 16 naval mines

The Type 201 was Germany's first class of military submarines built after World War II. They were built out of amagnetic steel to counter the threat of magnetic naval mines, but the material had been insufficiently tested and proved to be problematic in service with the Bundesmarine. Microscopic cracks in the pressure hull forced the cancellation of nine of the twelve ordered submarines and the early retirement of the three completed boats. They were replaced by the very similar Type 205 submarines, that were constructed with normal steel. Responsible for the design and construction was the Ingenieurkontor Lübeck (IKL) headed by Ulrich Gabler.

U-3 was loaned to the Royal Norwegian Navy and served under the name Kobben from 1962 to 1964 before being commissioned in the German Navy.

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