US Patent 8376264 Rotor for a dual mode aircraft

A rotor for use on an aircraft has a plurality (N) of rotor blades mounted on a plurality (N) of concentric masts. Each of the rotor blades has a rounded leading edge and a tapered trailing edge. The plurality (N) of concentric masts each operably mount one of the plurality of rotor blades at N different elevations. A locking element selectively locks or unlocks the concentric masts together in a plane of rotation, enabling the angle between any two rotor blades to be variable from 0-360 degrees during flight. A feathering hinge is operably attached to each blade for changing the pitch of each blade with respect to the plane of rotation as controlled by a pitch control mechanism.