Leonardo da Vinci's aerial screw was a rotating-wing design intended to rise vertically from the ground.
Leonardo drew the concept around 1489, describing a large helical sail made from reed, linen, and wire. His notes suggested that if the screw rotated rapidly enough, its spiral surface might push against the air and lift the machine.
The aerial screw is frequently called an early helicopter concept, but that comparison needs care. Leonardo's design did not have a powered engine, modern rotor blades, or a practical control system. Human muscle power would not have been sufficient to spin its large structure fast enough for sustained flight.
The design nevertheless anticipated an important principle used by later vertical-flight machines: a rotating lifting surface can generate upward force. Modern helicopters use powered rotors with carefully shaped airfoils, so Leonardo's aerial screw was a conceptual ancestor rather than a functioning helicopter.