The Pescara Model 3 was the first of several coaxial helicopter designs by Raúl Pateras Pescara to demonstrate sustained controlled helicopter flight.
Argentinian engineer Pescara started helicopter development in 1916. Alberto Santos-Dumont helped fund experimentation on designs in France. Multiple examples were built, demonstrated, crashed, improved and rebuilt owing to conflicting and different names for the various versions.[1] Anticipating success with the counter-rotating mechanism, Pescara patented a design with a streamlined fuselage with one set of rotors above, and one below the fuselage.[2]
The model three was the first example to use control mechanisms as modern helicopters. The helicopter is based around a central shaft with counter-rotating rotors. Each rotor was doubled into a biplane arrangement with cable supports.[3] It used a cyclic stick for forward and lateral control with rotor warping, and wheel for yaw anti-torque control.[4] The main rotor shaft was able to tilt slightly for forward control.[5] The rotors were also capable of autorotation in case of engine failure.[6]
In September 1923, a 1 km flight attempt was nearly completed, before the vehicle crashed. On 24 March 1924 Étienne Oehmichen set a world helicopter record flight of 358m. On 18 April 1924 the model 2F bested the record and flew 736m at 8 mph to set a record in sustained vertical flight.[7]
