The Hiller VZ-1 Pawnee (U.S. Army designation; earlier Army designation: HO-1) is a unique direct-lift rotor aircraft, using contra-rotating ducted fans for lift inside a flying platform upon which the single pilot shifted body weight for directional control.

The platform was developed starting in 1953 under an Office of Naval Research (ONR) contract to Hiller Aircraft, and flew successfully beginning in 1955.

[3] The smaller ONR model used two 44 horsepower (33 kW) Nelson H-59 piston engines, coupled to the propellers by a modified helicopter transmission built by the Industrial Power Division of Hall-Scott.

The larger Pawnee model used three of those engines and had an extended duct area.

Data from National Air and Space Museum[6] and Hall-Scott Motor Company[7]General characteristics Performance