What is the difference between a helicopter and a gyroplane?
During conventional flight, an engine continuously drives a helicopter’s rotor to provide lift, whereas a gyroplane features a free-wheeling rotor that windmills in rotation (autorotation) as a relative airflow transitions upwards through it. Without forward motion relative to the surrounding air, the gyroplane’s rotor will not maintain its rotation and will descend. This means that gyroplanes cannot hover or climb vertically. Some gyroplanes have provision for providing power to the rotor to “prerotate” it so that it has sufficient rpm to facilitate autorotation when beginning the takeoff role and some have the capability to overspeed the rotor on the ground for a “jump takeoff” when pitch is suddenly increased on the rotorblades, causing a short burst of lift. However, power cannot be provided to the gyroplane rotor in flight without some means in place to offset torque.
