Leonardo da Vinci’s spiral machine designed for vertical lift is commonly called the aerial screw.
Leonardo drew the aerial screw around 1489. The design shows a large helical surface wrapped around a central mast, with a framework intended to rotate it. Leonardo reasoned that the spiral surface might “screw” upward through the air in a manner resembling a screw moving through a solid material.
The sketch is often described as a forerunner of the helicopter, but that comparison needs care. Leonardo did not build a working helicopter, and the proposed mechanism lacked a practical lightweight engine. The design also did not include the modern helicopter’s separate rotor, tail rotor, and powered control systems.
Its importance lies in the idea of generating vertical lift with a rotating helical or rotor-like surface. Centuries later, powered helicopters used rotating blades based on aerodynamic lift rather than Leonardo’s fabric-covered spiral. The aerial screw is therefore an influential conceptual ancestor, not the first functioning helicopter.