Gyrocopter
A gyrocopter is an aircraft that looks like a helicopter, but the rotor blades are not powered by the engine. Instead the airflow from the forward motion of the aircraft forces the rotor blades to spin and thus lift is generated.
The gyrocopter might seem like a dangerous aircraft, but it's quite the opposite. If the engine fails, the gyrocopter can land safely by doing autorotation, meaning a controlled landing.
Here you will find resources to gyrocopter flying and gyrocopter manufacturers. Enjoy!