Technology / Aviation / Autogyro: An aircraft, often wingless, with unpowered rotary airfoil blades that auto-rotate and serve as wings as they move through the air when mounted on a powered aircraft (or, in some cases, a glider). The latter spelling is a trademark of the Autogiro Corporation.
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Technology / Aviation / Gyroplane: A rotorcraft whose rotors are not engine-driven, except for initial starting, but are made to rotate by action of the air when the rotorcraft is moving and whose means of propulsion, usually a convent MORE
Technology / Aviation / Auto-Rotation: Automatic rotation of rotary blades from a helicopter in an unpowered glide or the forward movement of an autogyro. MORE