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Old 26th Oct 2011, 15:12
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Gemini Twin
 
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bumblebee

Article fron Mondays Mecury News

SCOTTS VALLEY - A furiously pedaling teenager became the first person to test an ultra-lightweight, human-powered helicopter designed to break an international aviation record.
There was no actual lift-off Sunday inside the Scotts Valley High School gym. It was just an initial test run to see if the sheer effort of UC Berkeley student Kyle Zampaglione, 19, could make the 85-foot and 48-foot rotors spin.
"Today is the first time we have ever put it together," said aeronautical engineer Neal Saiki of Scotts Valley.
Saiki is aiming to claim the American Helicopter Society Igor I. Sikorsky Human Powered Helicopter Prize, a 31-year-old challenge to build a human-powered helicopter that can hover for one minute and, at some point, reach a height of 3 meters.
"This takes a while," he said. "This is a process. It's a lot of innovation."
The test took place after a full day of tinkering by Saiki and his volunteer crew, several of whom had been engineers on the successful attempt to break the world human-powered helicopter flight record in 1989. They stabilized rotors with guy-wires, taped together specially crafted lightweight components and pulled out a drill at the last minute to mend a broken tube.
The test was a way to look for the weaknesses. Saiki said the team had already made numerous adjustments to improve the model.
The craft will be the culmination of 20 years of planning and five years of construction, Saiki said. After
modifications, the vehicle, which is made up of about 200 specially designed lightweight pieces, should be ready for official testing in a few weeks.

"It will all come together," Saiki said. "People will get really excited. This is one of the last frontiers. This is the last aviation achievement to fall."
In 1989, Saiki, heading up a team of Cal Poly San Luis Obispo engineers, broke the record for human-powered helicopter flight. They designed and built a machine that rose nearly 8 inches off the ground for just more than seven seconds. (The professional bicyclist piloting the machine passed out from exertion after 10 seconds).
Saiki went on to design award-winning mountain bikes, medical devices, high-altitude research planes, climbing equipment and electric motorcycles. With his wife, Lisa, he co-founded Zero Motorcycles in Scotts Valley in 2006.
Four months ago, he retired from his post as chief technology officer at Zero and has been working around the clock on building the helicopter he's named the Upturn.
To qualify for the Sikorsky Prize, the helicopter has to be solely powered by muscle power with no stored energy and has to stay within a three-meter square area. The prize was recently increased from $20,000 to $250,000.
Saiki says he's put about $25,000 into the Upturn, which has attracted several small sponsors as well as volunteers. The total cost is about $40,000.
The Upturn weighs in at about 95 pounds. Saiki has designed all of the parts to be ultra-lightweight. Hollow links in an aluminum drive chain turn a spool of high-strength thread that stretches through hollow foam rotor blades and spins small propeller blades. Spectra guy-lines made of a plastic stronger than steel hold the machine in alignment. The pilot sits in the center in a balsa wood-framed seat.
The project needs an inside testing arena that's big enough - 130 feet in diameter - to accommodate a 3-meter lift and a competitive cyclist who is light enough - under 140 pounds - and strong enough to generate one horsepower of energy for one minute.
"This is pushing helicopter technology that is hundreds of times more efficient than normal helicopters that use 500 horsepower," he said.
The project is documented online at NTS Works.
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