Leonardo da Vinci designed an aerial screw as an early helicopter concept.
The drawing dates from about 1489 and shows a large helical rotor made from reed, linen, and wire. Leonardo reasoned that a rotating screw could press against the air and rise, much as a screw advances through a solid material. The proposed machine was intended to carry people, although Leonardo did not provide a practical engine capable of powering it.
The aerial screw is often described as a helicopter ancestor, but it was not a working helicopter. Its broad spiral surface would have been difficult to rotate quickly enough, and the structure would have been heavy. Modern helicopters use powered rotors with airfoils, control systems, and carefully balanced blades rather than Leonardo’s continuous helical surface.
Leonardo’s idea still mattered historically because it treated vertical flight as an engineering problem. The design appears in the Codex Atlanticus and demonstrates his interest in translating observations of air and motion into machines.