What was Leonardo da Vinci’s rotating flight device called?

Leonardo da Vinci’s rotating flight device was called the aerial screw.

Leonardo sketched the aerial screw in the 1480s, probably around 1489. The drawing shows a large helical surface made from linen and supported by a reed framework. Leonardo proposed that the screw would “screw” itself upward through the air when rotated rapidly, an idea that resembles the lift produced by a helicopter rotor.

The aerial screw was not a helicopter and was never demonstrated as a powered aircraft. Its proposed materials and human-power requirements would not have supplied enough thrust for practical flight. Nevertheless, the sketch is frequently discussed as an important early concept in the history of vertical flight.

The design is sometimes called a helicopter precursor, but that comparison should be treated carefully. Modern helicopters use aerodynamic rotor blades, engines, and precise control systems. Leonardo’s machine had a continuous spiral surface and lacked a workable power source and flight-control arrangement.