Abstract: A variable chord morphing helicopter rotor blade is disclosed. The variable chord morphing helicopter rotor blade includes an extensible quasi-static chord section connected to the rotor blade, an adjusted airfoil chord length of the rotor blade corresponding to extension of the quasi-static chord section relative to a baseline airfoil chord length, the adjusted airfoil chord length determined according to helicopter flight conditions.

Abstract: A variable diameter helicopter rotor and method of using are disclosed. The variable diameter helicopter rotor includes a rotor hub operable by helicopter controls at variable revolutions per minute, and a linearly extensible rotor blade connected to the rotor hub, a linear span of the rotor blade only adjustable in response to an amount of centrifugal force generated in the rotor blade by a rotational speed of the rotor hub, an operational rotor blade to effect at least lift of the helicopter. The linearly extensible rotor blade can include telescoping inner and outer sections, and a restrictive force device positioned between the inner and outer sections. The variable diameter helicopter rotor can be used by adjusting a linear span of rotor blades connected to the rotor hub by an amount corresponding to an amount of centrifugal force generated in the rotor blades by a rotational speed of the rotor hub.