Abstract:
A drag operated collective pitch control system is provided for gyroplane rotary wing aircraft. The system employs drag surfaces which are selectively engaged while the hub is rotating to actuate the system. Each blade mount is provided with a feathering pivot. Pinion gears control the pitch of each blade, and the pinions, mounted on the hub, are engaged by a pair of ring gears, also carried on the hub. To operate the system, either one or the other of the ring gears, to which the drag surfaces are coupled, is engaged by suitable drag means. The pitch of all the blades is thereby adjusted simultaneously.