Cristea Constantinescu CO-2


In 1934 Major Cristea Constantinescu (B.Sc.,Eng.) designed an autogyro-helicopter, called C.O.-1, with a pusher airscrew and two co-axial rotors. Having tested the model of the aircraft and being dissatisfied with the over-complicated construction of the two rotors Eng. Constantinescu designed the C.O.-2 helicopter. In 1938 the finalized design was submitted to the Air and Navy Ministry, after the successful testing of the helicopter's mock-up in the wind tunnel of the Polytechnical Institute of Bucharest. One of the rotors of the helicopter, built to size and attached to the engine, successfully passed ground tests on the proving stand before a commission of the Ministry, giving the results specified by the design.

Although the C.O.-2 helicopter was not completed because of lack of funds, its design was a valuable advance, the main point of interest residing in the original conception and the new structural solution found for it (two co-axial rotors, anti-torque propeller, aerodynamic cockpit etc.). Unlike the helicopters built and tested at the time (Breguet-Dorand and Focke-Wulf F.W. 61), the C.O.-2 helicopter, although designed more than 30 years ago, was very similar to the helicopter models built today.

"Romanian Aeronautical Constructions - 1905-1974", 2009

Rotor diameter: 8.00m; anti-torque propeller diameter: 1.80m; length: 7.30m; height: 3.20m; total area of rotor blades: 5.76m; rotor revolutions: 188rpm; total weight: 410kg; engine: 90hp Pobjoy-Niagara; reduction rate: 10.40; horizontal calculated speed: 132km/h.