Leonardo da Vinci’s 1480s design for a vertical-lift flying machine is commonly called the aerial screw.
Leonardo sketched the machine in the Codex Atlanticus, probably around 1485. Its central idea was a helical surface made from reeds and covered with linen, which would rotate and theoretically screw upward through the air. The drawing is often described as an ancestor of the modern helicopter, although it was never built or tested by Leonardo.
The aerial screw was a concept rather than a practical aircraft. Its proposed materials and human-powered operation could not provide enough lift, and Leonardo did not establish a working engine or rotor system. The design also differs from a modern helicopter, whose rotating blades generate lift through aerodynamic airfoils.
A common mistake is to call it Leonardo’s “first helicopter.” That description is retrospective: the sketch anticipated vertical flight but did not demonstrate it.