What are gyrocopters?

Gyroplanes are rotorcraft in which no engine power acts on the main rotor, but instead the airstream drives the rotor like a windmill/wind turbine.

The forward flight is usually generated by a motor-driven propeller.
However, if no motor is installed, it can also be towed by a tow rope (motorboat or similar) or flown like a hang glider without external power.

In principle, the air flows from bottom to top in a gyroplane and from top to bottom in a helicopter, unless the helicopter's engine has failed and autorotation is necessary.