Leonardo da Vinci’s aerial screw was the flying-machine concept that used a large helical rotor to rise through the air.
Leonardo drew the aerial screw in a notebook around 1489. The sketch shows a broad, spiral-shaped surface wrapped around a central mast, with a platform and supports beneath it. His notes proposed that rotating the structure could make the helical surface press against the air and lift the machine.
The design is often described as an ancestor of the modern helicopter, but that comparison needs care. Leonardo’s machine had no engine, and the human crew shown in related reconstructions could not produce enough sustained power to lift it. The drawing represents an aerodynamic idea rather than a flight-tested aircraft.
The aerial screw also illustrates Leonardo’s interest in studying birds, air resistance, and mechanical power. Modern helicopters use powered rotors with airfoils and are aerodynamically very different. The resemblance lies mainly in the use of a rotating lifting system above the vehicle, not in a directly workable Renaissance helicopter.