In a helicopter, the rotor is made to turn by the engine. The engine is connected to the rotor blades through a gearbox and driveshaft. The gearbox increases the speed of the engine and transfers the power to the rotor blades. The driveshaft connects the gearbox to the rotor hub, which is the central part of the rotor. The rotor hub is attached to the rotor blades, which are free to rotate around the hub. When the engine is running, the gearbox and driveshaft turn the rotor hub and the rotor blades. The air flowing over the rotor blades creates lift, which causes the helicopter to rise into the air.
In an autogyro, the rotor is made to turn by the airflow over the rotor blades. As the autogyro moves forward, the airflow over the rotor blades creates lift, which causes the autogyro to rise into the air. The rotor is not powered by an engine, so the autogyro cannot ascend vertically like a helicopter. However, the autogyro can fly at a lower speed and is more fuel-efficient than a helicopter.
