1483 Aerial Screw (Leonardo Da Vinci)

Many people see the Aerial Screw, designed by Leonarda DaVinci in 1483, as the first helicopter design. It can be found in folio 83v from Manuscript B. Note that the design uses a screw rather than a propeller or rotating wing. Yet, DaVinci was aware that the air is very thin, and that the screw had to be large and rotate quickly. He never actually built the machine, although a replica was produced in the 20th century, but was unable to fly.