The core of GAC’s Gyroplane and Gyrodyne technology is GAC’s unparalleled understanding of sustained autorotative flight. Autorotation is the ability of a free-spinning rotor to generate lift.


For a Gyroplane in forward flight, as shown in the diagram above, the unpowered rotor creates lift through autorotation, with forward thrust provided by an engine-driven propeller(s) or by jet engine(s). Gyroplanes can be capable of vertical takeoff and landing, as are all GAC Gyroplanes, the former by “prerotating” the rotor on the ground using main engine power, and then converting that rotational energy into vertical lift. Since autorotation requires forward movement, Gyroplanes cannot hover.

picture 2

A Gyrodyne, as shown in the diagram above, is a gyroplane to which thrust-jets (reaction drives) are added to the rotor tips to power the blades, enabling both hovering and substantial lifting capacity. In forward flight, the tip-jets are turned off and the rotor flies in autorotation like a gyroplane, greatly extending its range while still maintaining a fraction of the complexity of helicopters.

While visually both the gyroplane and gyrodyne resemble a helicopter, each is closer in design to a fixed-wing airplane. Gyrodynes and many gyroplanes have everything that an airplane has: wings, tail, ailerons, elevator, rudders, and main engines used for forward thrust (propellers or turbofan). The only element of a helicopter that is common to it and a gyroplane/gyrodyne is its rotor system: rotor blades, head, and controls; but none of a helicopter’s complexity: transmissions, gearboxes, tail rotors, drive shafts, etc. It is these complexities that cause helicopters to be both expensive in acquisition and operation, and unreliable, needing a great deal of maintenance.