Assemble set series The Aerial Screw designed by Leonardo da Vinci was a precursor of the modern day helicopter. The device was designed to compress air in order to obtain flight. Measuring more than 15 feet in diameter and made from reed, linen and wire, the machine called for a four-man team to stand on a base and employ a pumping action to spin the rotary blade in order to lift the device off the ground. Da Vinci was a big proponent of the many possibilities offered by the screw shape, and he used the shape for other inventions and designs as well. Interpretation of the original Leonardo da Vinci's design/ copyright by Leonardo3 - www.leonardo3.net - All rights reserved