Leonardo da Vinci called his 1489 rotating aircraft concept the aerial screw.
The drawing depicts a helical structure wrapped around a central mast. Leonardo reasoned that, if rotated rapidly, the screw might push against the air and rise, much as a screw moves through a solid material. The design is usually described as a precursor to the modern helicopter rather than a workable helicopter itself.
Leonardo’s sketch does not provide a practical engine, lightweight materials, or a complete control system. The proposed frame was large and heavy, and human muscle power would not have supplied enough energy for sustained flight. Its importance lies in identifying vertical lift as a distinct aviation problem and in presenting a recognizable rotor-like idea centuries before powered helicopters became possible.
The aerial screw is sometimes casually called Leonardo’s helicopter. That label is useful as a comparison, but “aerial screw” is the historical name associated with his drawing.