Leonardo da Vinci’s 1489 rotating-air machine was called the aerial screw. His drawing presents a large helical structure intended to press against the air and lift an entire craft, making it one of the best-known early helicopter concepts.
The design appears in Leonardo’s manuscripts and is often dated to around 1489. He proposed a frame covered with reeds, linen, and starch, with a screw-like rotor roughly 2 metres in radius. The idea resembles an airborne version of the Archimedean screw, which moves through water rather than air.
Leonardo’s aerial screw was never demonstrated as a working aircraft. The materials, power source, and weight would have prevented the original design from generating enough lift. Nevertheless, it shows that he understood the relationship between rotating surfaces and upward force centuries before powered helicopters became practical.
It is better described as a helicopter precursor than as an actual helicopter. Modern helicopters depend on powered rotors and aerodynamic principles unavailable to Leonardo.