coaxial rotors


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coaxial rotors

A rotor system in which two rotors are mounted on the helicopter rotating in the opposite direction but running on concentric shafts. There is thus no residual torque.
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VRT500 is a light single-engine helicopter with coaxial rotors. Its takeoff weight is 1,650 kg.
VRT500 is a light single-engine helicopter with coaxial rotors and maximum take-off weight of 1600 kg.
AVX has developed and has patented a unique compound helicopter configuration with coaxial rotors and dual ducted fans that combine proven technologies to achieve greater aerodynamic efficiency, speed, range, fuel efficiency, Hover Out of Ground Effect (HOGE) and utility than conventional helicopters.
[16] developed and experimentally validated a source-doublet panel method to investigate effects of different design parameters on the hovering performance of coaxial rotors.
An S/c of 1.335 is an extreme case where modern day coaxial rotors do not operate.
Last year, the Army downselected from four vendors to two--a Boeing-Sikorsky team offering the SB-1 Defiant, a compound helicopter with coaxial rotors, and Bell Helicopter offering the V-280 Valor, a tilt-rotor aircraft.
The Kamov Design Bureau (design office prefix Ka) has more recently specialized in compact helicopters with coaxial rotors, suitable for naval service and high-speed operations.
As a tail rotor typically wastes some of the power, otherwise it can be devoted to lift and thrust, however, in coaxial rotors all of the available engine power is devoted to lift and thrust.
Coaxial rotors are also used on China's Haiou (Seagull) drone developed by the Beijing University of Aeronautics and Astronautics.
Interestingly, the runner-up for the Mavdem was a conventional helicopter configuration with a low-drag fuselage and a sensor pod mounted between two coaxial rotors.
AVX and the Boeing-Sikorsky team are offering compound helicopters with coaxial rotors. Bell-Lockheed and Karem have put forward tilt-rotor designs.
The S-97 will have coaxial rotors and a pusher propeller, as tested with the two-seat 3600-kg X2 demonstrator.