Leonardo da Vinci sketched a helicopter-like aircraft as an aerial screw in the 1480s.
His drawing shows a large helical sail or screw intended to rotate around a central mast. Leonardo reasoned that a rapidly turning spiral surface might screw itself upward through the air, much as a wood screw advances through material. The design was probably inspired partly by the Chinese flying top, a toy known in Europe through descriptions and examples.
The aerial screw was not a working helicopter. Its proposed linen-covered frame was far too large and heavy for the human power available in Leonardo’s time, and the design lacked a practical engine or rotor-control system. Modern helicopters instead use powered rotors that generate lift through aerodynamic airfoils.
The drawing is often called Leonardo’s helicopter, but that name is retrospective. Leonardo did not build a functioning aircraft, and his concept differs mechanically from modern helicopters even though it anticipated the broad idea of vertical flight.