Powered autogyro versions of the auto-kites have been developed simultaneously, the first of these being the B-7M which flew for the first time on 6 December 1955. This was followed on 8 July 1957 by the first B-8M (M = motorised) and by the first production B-8M on 9 October 1957. The B-8M is normally powered by a 72hp McCulloch piston engine. Optional features include a 90hp McCulloch engine and a mechanical rotor drive enabling the autogyro to make jump starts. A float version of the B-8M is known as the Hydro-Copter.

K.Munson "Helicopters And Other Rotorcraft Since 1907", 1968

Technical data for B-8M Engine: 1 x McCulloch Model 4318 pistone engine, rated at 54kW, main rotor diameter: 6.1m, fuselage length: 3.45m, height: 1.19m, take-off weight: 227kg, empty weight: 112kg, max speed: 137km/h, cruising speed: 72km/h, service ceiling: 3810m, range: 161km

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