What did Leonardo da Vinci’s aerial screw concept use to create lift?

Leonardo da Vinci’s aerial screw concept used a helical screw to create lift.

Drawn around 1489, the aerial screw is one of Leonardo’s best-known flight studies. His sketch shows a large helical surface wrapped around a central mast, with a platform and people arranged beneath it. Leonardo reasoned that, if the screw rotated quickly enough, its spiral surface could bite into the air and raise the machine.

The idea resembles a helicopter rotor in its goal of producing vertical lift, but it would not work as drawn with the materials and human power available in the Renaissance. A modern helicopter uses rotating airfoils, an engine, and carefully controlled rotor aerodynamics rather than a solid screw-shaped surface.

The aerial screw was a conceptual machine, not a completed aircraft. Its importance lies in showing Leonardo’s attempt to analyze flight mechanically. It is sometimes incorrectly described as the first helicopter; it was an early vertical-flight proposal, not a functioning helicopter.