Leonardo da Vinci called his screw-shaped flying-machine concept the aerial screw.
Leonardo drew the aerial screw in a manuscript usually dated to about 1489. The design showed a helical surface wound around a vertical central shaft. He reasoned that if the screw were rotated quickly enough, it might rise through the air in a way comparable to a screw moving through a solid material.
The sketch is frequently described as a helicopter precursor, but it was not a helicopter in the modern engineering sense. It had no engine, rotor-control system, or practical means of generating the required power. Modern helicopters use rotating airfoils, whereas Leonardo's design was based on a continuous helical surface.
The aerial screw remains important because it shows Leonardo thinking about vertical flight centuries before powered helicopters became possible. The name comes from the machine's screw-like geometry, not from a known successful flight.