Theory of helicopter damping in pitch or roll and a comparison with flight measurements

Kenneth B. Amer
naca-tn-2136
Oct 1950


Calculations and flight-test measurements on a single-main-rotor helicopter indicate that the damping moment about the helicopter center of gravity produced during pitching or rolling by a rotor which has flapping hinges on the rotor shaft depends primarily upon four quantities: rotor speed, blade mass factor, height of the rotor hub above the helicopter center of gravity, and the ratio of collective pitch to the thrust coefficient-solidity ratio.

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