Leonardo da Vinci’s four-winged flying-machine sketch is commonly called a helicopter.
Leonardo’s aerial screw, drawn around 1489, showed a helical sail intended to rise by turning through the air. The machine had a broad spiral structure made from reeds and linen, with a central mast and a platform. Leonardo reasoned that if the screw moved rapidly enough, it might “screw” itself upward.
The nickname “helicopter” is useful for comparison, but the sketch was not a working helicopter in the modern engineering sense. It had no practical engine, and the human crew shown in related reconstructions could not generate enough power to lift it. Modern helicopters instead use powered rotors that create lift and allow controlled flight.
The aerial screw remains important because it shows Leonardo studying vertical flight centuries before powered rotorcraft became possible. Its spiral principle is often compared with the later helicopter, though the machine’s shape and operating method were substantially different from those of a modern aircraft.