Human-powered helicopter takes flightPosted: May 14, 2011
Engineering students at the University of Maryland have successfully tested Gamera, a massive pedal-powered chopper. Gamera has four 13-metre wide rotors, one at each end of its 18-metre wide cross-shaped carbon-fibre frame, but weighs less than 100kg – including the human pilot, Judy Wexler, who sits in the middle and provides power through both hand and foot peddling. Wexler successfully lifted off after two days of testing, managing to get several inches off the floor for about four seconds. “We’re ecstatic,” says Brandon Bush, Gamera team leader. Though the team of more than 50 students were pleased to finally get airborne, they failed to achieve their ultimate goal of claiming the American Helicopter Society’s Sikorsky Prize. The prize, worth $250,000, requires a human-powered helicopter to hover for a full minute while remaining within a 10-metre square. It must also fly higher than three metres at one point. Human-powered aeroplanes have been successful in the past, such as when the Gossamer Albatross flew across the English Channel in 1979, but flying a helicopter is more challenging as they must be much lighter and more efficient. Both Gamera and Yuri 1 achieve flight by exploiting the ground effect, an increase in lift that occurs when an aircraft flies close to the ground. Gamera actually uses an “extreme” ground effect, with the rotors less than five per cent of their length off the ground.
Source: www.newscientist.com, May 13, 2011