Aerial screw
Trade between East and West brought Chinese toy bamboo ‘helicopters’ to Italy, which can be seen in paintings of the Renaissance period.
Da Vinci’s human-powered aerial screw describes the progress up through the air of the rotors of a modern helicopter, but even if it got off the ground, the attached body of his device would counter-rotate, making for a giddy and uncontrollable ride.
The dream of vertical flight inspired experiments with models for another four hundred years incorporating feathers, springs, rubber bands, steam and internal combustion engines.
In Federation-era Australia, Ngarrindjeri man David Unaipon – an accomplished inventor and writer – developed drawings for a helicopter based on the aerodynamics of the boomerang.
By 1907 Gyroplane No 1 built by the Breguet brothers in France, had flown for 60 seconds at a height of 0.6m, but it was so unstable the undercarriage had to be held down. Following a number of similar successful experiments,
Spain’s Juan de la Cierva flew an autogyro in 1923, a hybrid of a helicopter and aeroplane.
As World War II loomed the race to develop a military helicopter accelerated Heinrich Focke designed the first twin rotor helicopter in 1936, and Igor Sikorsky built a single rotor version in America that became the prototype of today’s helicopters.
In 2013 a team of engineers from Aerovelo in Canada flew their experimental super lightweight Atlas helicopter under pedal power for 64.1 seconds, reaching an altitude of 3.3m.
IMAGE: Atlas human powered helicopter
Photo: http://www.aerovelo.com/
Aerial screw
painted wood and canvas