German U-Boat

The Hecht was inspired by the successful attack on British battleships at Alexandria harbor by Italian human torpedoes on the night of December 18 1941, that Admiral Donitz submitted a plan to build submersible weapons capable of undertaking such missions. The result was the Hecht, a two man midget submarine designed to carry a 800kg limpet mine at its bow which could be dropped under the hull of an enemy ship.

Subsequent missions however required it to be fitted with a torpedo to attack moving targets. The redesign required the submarine to carry either a single torpedo under its hull or a mine at its bow. Fifty three orders were placed, but construction was halted after three prototypes were built. Their performance proved unsatisfactory and it became apparent that a more promising version could be built.

Powered exclusively by electric motors, the Hecht’s range of 65nm surfaced and 35nm submerged was too short for any practical purpose. A later version was planned where the Hecht would feature an exchangeable bow for carrying additional battery cells or two divers (instead of a mine), but neither of these were realized. Built by Germaniawerft in Kiel, the three prototypes were delivered in May 1944 but none of these saw action. Instead, they were relegated to training purposes.

The blunt nose carried a limpet mine, which could be dropped off under enemy ships. In this photo, its armed with a torpedo under its hull.

Hecht Type XXVIIA Specification
Displacement	11.83 tons
Dimensions Length Beam Diameter	34.1ft (10.39m) 5.6ft (1.7m) 4.3ft (1.3m)
Top speed Surfaced	5.7 knots
Maximum range	65nm at 5.7 knots
Motor output	8.8kW
Diving depth	164ft (50m)
Armament	One 21 inch torpedo or one mine
Crew	2
Number built	3 (53 planned)