What name is given to Leonardo da Vinci’s rotating-helix aircraft concept?

Leonardo da Vinci’s rotating-helix aircraft concept is called the aerial screw.

Leonardo drew the aerial screw around 1489, depicting a large helical structure intended to rise when rotated. The design is often discussed as an early helicopter concept because its proposed lift came from a rotating screw or rotor rather than from flapping or fixed wings.

The aerial screw was not a practical helicopter. Leonardo’s drawing suggests a large linen-covered framework, and the machine would have required far more power than people of the period could supply. It was therefore a theoretical flight study rather than a tested invention.

The aerial screw is sometimes loosely called a helicopter, but that can create a historical mix-up. Modern helicopters use powered rotors, control systems, and lightweight structures developed centuries later. Leonardo’s sketch is important because it identified a rotor-based route to vertical flight, even though it did not solve the engineering problems.