Leonardo da Vinci's proposed vertical-lift machine from about 1489 is commonly called the aerial screw.
The aerial screw was drawn as a large helical structure made from reeds, linen, and wire. Leonardo reasoned that if the spiral surface rotated rapidly enough, it might screw upward through the air, much as a screw moves through a material. The concept is often described as a distant precursor to the helicopter.
Leonardo did not build a full-scale working aerial screw, and the design lacked a practical power source. Its large size and heavy materials would also have made sustained lift extremely difficult. The idea is therefore best understood as a theoretical investigation of vertical flight, not as the first helicopter.
The aerial screw should not be confused with Leonardo's ornithopter, which relied on flapping wings, or his parachute, which relied on drag during descent. Modern helicopters use powered rotating blades with carefully shaped airfoils, a substantially different aerodynamic solution.