Leonardo da Vinci drew an aerial screw as a rotating, screw-shaped flying-machine concept in the 1480s.
The design appears in a manuscript usually dated to around 1489. It shows a large helical surface wrapped around a central mast, with a framework intended to rotate the screw. Leonardo reasoned that the screw might rise by driving air downward, an idea that resembles the basic lift principle of later rotary-wing aircraft.
The aerial screw was a conceptual study, not a functioning helicopter. It lacked a practical engine, suitable lightweight materials, and a proven method for producing the necessary rotation. The drawing is nevertheless important because it shows Leonardo thinking about vertical flight rather than only flapping wings or gliding.
People sometimes call it the first helicopter. That description is only a loose comparison: helicopters use powered rotors and controllable flight systems, whereas Leonardo’s aerial screw was an unbuilt Renaissance proposal.