Leonardo da Vinci designed an aerial screw, a helicopter-like flying machine with a large rotating helical rotor.
He sketched the concept around 1489, imagining a linen-covered helical surface that would “screw” upward through the air. The design was probably inspired partly by the flight of seeds and by Archimedes’ screw, a machine used to lift water. Leonardo’s drawing included a central mast and a circular platform for the crew.
The aerial screw could not fly as drawn because human muscle power would not have been enough to rotate its rotor rapidly. It also lacked a modern helicopter’s lightweight materials, engine, and aerodynamic rotor blades. Even so, it is widely remembered as an important early study of vertical flight, not as a machine Leonardo successfully built or flew.