In 1980, the American Helicopter Society offered US$20,000 for the first group to build a human powered helicopter. It had to hover in a 10 metre square zone for a minute and reach a height of three metres. Since then around 20 unsuccessful attempts have been made but the University of British Columbia will have a try tomorrow, August 10.

Their “Thunderbird” is based around two rotors rotating in opposite directions. The upper rotor is actually longer than the wing span on a 737 and plans call for the upper rotor to rotate at 3.5 rpm and the lower rotor at 6 rpm, giving a lift of 137 kilos. That’s the amount of weight that the pilot and helicopter must weigh less than for the Thunderbird to get off the ground.

From Gizmo.