The A.E.G. helicopter designed by R. Schmidt in 1933 resembled the Petroczy-Karman aircraft used in World War I. The A.E.G. was attached to the ground by a system of three tethering cables which helped to stabilize it so that it could be used as an observation post or, if need arose, as a support for an aerial.
The co-axial contra-rotating two-bladed rotors were driven by an electric motor located between them and fed with power through the three anchoring cables attached to girder-type arms fixed above the upper rotor. These tethering girders supported the observer's cabin; in the event of engine failure, the observer escaped by using a parachute blown into the air by a powder charge. The helicopter could be transported to the point where it was to be used in a special lorry fitted with a launching stand and a control desk.
Despite successful trials, the AEG helicopter does not appear to have been adopted for military use, probably because of the impracticability of having to find a considerable electric current supply.