Leonardo da Vinci’s invention sketched around 1485 is called the aerial screw.
The design appears in a manuscript drawing showing a helical linen sail wrapped around a central mast. Leonardo suggested that turning the screw could make it rise through the air, much as a screw advances through a material. The drawing is one of his best-known studies of vertical flight.
The aerial screw was not a functioning helicopter. It lacked a practical power source, lightweight materials, and a tested mechanism for producing enough lift. Modern replicas have explored the design, but they do not establish that Leonardo’s machine could have flown as drawn.
The concept is often linked to helicopter history because its rotating spiral resembles a rotor. However, a helicopter uses rotating blades that generate lift aerodynamically, while Leonardo’s proposal relied on a continuous helical surface.