Leonardo da Vinci developed concepts for a giant air screw late in the 15th century. This working model uses a bevel gear, also from his drawings, to spin the canopy and support structure, illustrating the way Leonardo thought flight might be possible. A fun and inspiring project from one of the greatest minds of history. Easy to make from pre-cut and pre-drilled sustainable timber. Finished model size is 38cm high by 23 cm wide. On display at the Leonardo da Vinci museum in Rome: Air Screw model at da Vinci museum in Rome from Nigel Kirby on Vimeo.