Leonardo da Vinci’s 1480s rotating, screw-shaped flying-machine design is called the aerial screw.
Leonardo sketched the concept in the Codex Atlanticus, probably around 1489. Its design used a large spiral surface, or “screw,” intended to push against the air and lift the machine when rotated. The drawing resembles a helical rotor rather than an airplane with fixed wings.
The aerial screw is often described as an early helicopter idea, but it was not a working helicopter. Leonardo did not have a practical engine or sufficiently light materials to power and support such a machine. Modern recreations generally treat it as a conceptual ancestor of rotary-wing aircraft, not as the first helicopter itself.
The design is also sometimes called Leonardo’s “helicopter,” but that modern label can obscure the important difference between the sketch and a powered aircraft. Its historical importance lies in recognizing vertical lift through a rotating surface.