A team of students has finally claimed a $250,000 prize for building a functional, human-powered helicopter.
Since 1980 the American Helicopter Society has offered the Igor I. Sikorsky Prize to anyone who can keep a helicopter in the air for 60 seconds, at least three metres off the ground, without drifting outside an area of 10 metres by 10 metres.
But despite coming close, no team had been able to satisfy the society's demanding rules.
Undeterred, a team from the University of Toronto and AeroVelo, led by Cameron Robertson and Todd Reichert, decided to get in on the game, and built their own craft called 'Atlas' after drawing funds from Kickstarter.
While recognising the challenge was "one of the most daunting aviation feats of the past century", they were convinced they had the winning formula.
The machine they built has four huge rotors, connected to a massive but ultralight frame. It is powered by a modified bicycle, which can be operated by a single person.
After hiring a stadium for five days to test the machine, Reichert piloted the Atlas for 64.11 seconds, with a top height of 3.33 metres - within a square of 9.8 metres.
It was not easy.
"You're not thinking about how nice it is to be flying with your feet," Reichert told The Wall Street Journal. "You're thinking, 'I'm a machine.' The level of physical and mental focus was like nothing I've ever experienced before."
"We're very excited for the world to learn about this exciting milestone in aviation history. At AeroVelo we hope to inspire people to take on great challenges and accomplish the impossible. We would like the public to understand that with innovative engineering and creative design we can find sustainable and environmentally conscious solutions to many of the technological challenges facing our generation."
This incredible flight was 64.11 seconds in duration (World Record for "Duration on Hover"), reached a 3.3m peak altitude, and drifted a maximum of 9.8m. The Atlas as flown on June 13th behaved very differently from the aircraft we first flew some 9 months ago, a result of many incremental improvements and changes. In 18 months this passionate team went from preliminary design to achieving what many considered impossible, taking down one of the most daunting aviation feats of the past century."