Gyrodyne

The Gyrodyne is a type of VTOL (Vertical Take-Off and Landing) aircraft that utilizes a rotor for vertical lift and a separate propeller (or propellers) for forward thrust. This distinguishes it from a helicopter, which uses its rotor for both lift and propulsion. A gyrodyne typically uses powered rotors for takeoff and landing, and transitions to forward flight by using the propeller(s) to pull or push the aircraft, with the rotor then autorotating (freely spinning) to provide lift. Some designs maintain powered rotor rotation during forward flight. The gyrodyne concept attempts to combine the hovering capabilities of a helicopter with the higher forward speed and efficiency of a fixed-wing aircraft.