The Hecht (German: "Pike"), also known as Type XXVIIA, was a two-man all-electric German midget submarine created during World War II. The origin of the Hecht began with the salvage of the two British X class submarines HMS X6 and X7 which had been sunk during Operation Source, an attempt to sink the German battleship Tirpitz. Hauptamt Kriegschiffbau subsequently produced a design for a two-man submarine based on inspection of the British boats, designated Type XXVIIA and named Hecht ("Pike"). Like the British X class boats, the Type XXVIIA was designed to carry explosive charges to be laid beneath enemy ships, but it was markedly smaller and had substantial differences from the X class. It dispensed with a dual diesel/electric propulsion system, relying instead solely on electrical power in the form of a 12 hp AEG torpedo motor, on the basis that since it would operate submerged there was no need for a diesel engine. However, this resulted in a very low endurance of 69 nmi at 4 knots.
Externally, Hecht resembled the British Welman submarine. The detachable explosive charge was fitted to the nose of the submarine, while the forward section held the battery and a gyrocompass, the first to be fitted to a German midget submarine and considered essential for navigation since the craft was intended to operate almost exclusively below the surface. Behind this was the control compartment with seats for the two man crew arranged one behind the other on the centerline with the engineer in front and the commander behind him. The commander was provided with a periscope and a clear acrylic dome for navigational purposes. Fifty-three Hechts were built in total between May and August 1944, but their unsatisfactory performance meant they never saw action, and were mostly used for training Seehund crews.