Leonardo da Vinci designed an aerial screw, a lifting machine with a large screw-shaped rotor intended to rise through the air.
The concept appears in a drawing dated about 1489 and is often described as one of the earliest recorded ideas for a vertical-lift aircraft. Leonardo proposed a linen-covered helical surface supported by reeds or other lightweight materials. His notes suggest that the rotating screw would “screw” itself upward through the air.
The aerial screw was never built as a working aircraft in Leonardo’s lifetime. The design lacked a suitable engine and a practical way to generate enough sustained power. Modern analysis also shows that the proposed rotor would not operate like a modern helicopter rotor, because its surface and power arrangement were fundamentally different.
The machine is frequently called a helicopter in popular accounts, but “aerial screw” is the more precise historical term. It is distinct from Leonardo’s later studies of flapping-wing machines, which sought lift through birdlike wing motion rather than a helical rotor.