Leonardo da Vinci’s transport machine with a large wing-like rotor was the aerial screw.
The aerial screw was a proposed vertical-flight machine, drawn in Leonardo’s notebooks near the end of the 15th century. Its broad spiral surface was meant to rotate and create upward force, making the craft an early conceptual ancestor of the helicopter.
Leonardo did not have an engine powerful or light enough to operate it. The design also lacked the aerodynamic understanding and control systems needed for stable flight. For that reason, it should not be described as a successful aircraft or as a machine that Leonardo personally flew.
The term can cause confusion because modern helicopters use rotating blades rather than one large fabric screw. Nevertheless, both concepts depend on rotating lifting surfaces. Leonardo’s drawing is valuable because it shows him exploring vertical takeoff rather than only gliding or flapping-wing flight.