What name is given to Leonardo da Vinci’s rotating aerial-machine concept?

Leonardo da Vinci’s rotating aerial-machine concept is called the aerial screw.

Leonardo drew the design around 1489. It shows a helical sail or screw made from linen stretched over a reed framework, supported by a central mast and circular platform. His notes suggested that turning the structure could make it rise by pressing against the air, in a way loosely analogous to a screw moving through a material.

The aerial screw is frequently described as an early helicopter or helicopter ancestor. That comparison is helpful visually, but the machine was not a helicopter in the modern engineering sense. It lacked a practical power source, a controllable rotor system, and the aerodynamic understanding needed for sustained vertical flight. Its large, heavy structure would also have posed serious technical problems.

The idea nevertheless shows Leonardo’s attempt to apply mechanical principles to flight. The design is preserved in the Manuscript B of the Institut de France and is among his best-known studies of aerial machines.