INVESTIGATION OF ADJUSTABLE TIP WEIGHTS FOR IMPROVEMENT OF HELICOPTER STABILITY THROUGH INCREASED DAMPING

摘要

In accordance with Navy Department Contract NOw-62-0313-t, Task Order 62-2, an investigation was made by means of whirl test, of new concepts for improving helicopter stability. The objective of this Contract, which was administered by the Bureau of Naval Weapons, was to determine the feasibility of using rotor blade motions and the inherent gyroscopic forces as a source of additional damping in pitch and roll. The desired rotor stabilizing forces would be produced by weights attached at the tips of the main rotor blades and located well forward of the 25 percent chord. For the controls free case, or the con¬trols fixed case for a helicopter equipped with a flexible control system, these stabilizing forces would cause properly phased cyclic pitch changes which would lead to added rotor damping.