In 1973 aircraft manufacturer Heinrich Brditschka and an engineer with the Graupner model-building company, Fred Militky, enlisted the collaboration of Bosch (propulsion motor) and Varta (nickel-cadmium battery technology) to study the feasibility of an all-electric aircraft.
They converted an HB-3A motor glider into the first electric manned airplane: the MB-E1 (Militky-Brditschka Elektroflieger No. 1).
On 21 October 1973, the MB-E1 took to the skies in Wels, Austria with Heinrich’s son, Heino Brditschka, at the controls. The maiden flight lasted for about 9 min and achieved an altitude of 300 m. However, further advancement in battery and motor technology would be required to achieve practical electric flight.
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