Leonardo da Vinci’s aerial-screw concept is often described as a precursor to the helicopter.
Leonardo drew the aerial screw in the Codex Atlanticus, probably around 1489. The design shows a large helical surface intended to rotate and push against the air, much as a screw advances through water. Leonardo reasoned that if the screw were made from a light framework covered with reeds and fabric, it might rise from the ground.
The drawing is not a helicopter blueprint. It lacks a practical power source, and the proposed materials and human effort would not have produced enough lift for sustained flight. Modern helicopters instead use powered rotor blades and carefully engineered aerodynamics.
The aerial screw remains important because it shows Leonardo thinking about vertical flight separately from winged flight. It is one of his best-known aviation studies, alongside his ornithopter and parachute designs.