Leonardo da Vinci's spiral air-machine design is known as the aerial screw.
Leonardo sketched the aerial screw in the Codex Atlanticus, probably around 1489. The machine has a helical surface wrapped around a central framework, resembling a giant screw. He reasoned that turning the structure could make it rise by pushing against the air.
The aerial screw was not a powered aircraft and was never built or flown by Leonardo. Its proposed lifting principle is commonly compared with the rotor of a helicopter, but the engineering and materials available in the Renaissance were not sufficient to make the design practical.
The name can cause confusion because Leonardo created several flying-machine studies. The aerial screw is specifically the corkscrew-shaped concept, while his ornithopter drawings imitate the flapping motion of bird wings.