Now, the Canadian team AeroVelo has finally done it with the Atlas, a copter that looks more like a gigantic ceiling fan than an aircraft.

Hot on their heels was a team from the University of Maryland, both gunning for the $250,000 Sikorsky Prize and the dream of human-powered flight. (See: "If We Only Had Wings: The Daring Dream of Personal Flight.")

The challenge sounded simple enough: Fly three meters off the ground for 60 seconds while keeping the cockpit within a ten-square-meter area. But in the nearly three decades since the American Helicopter Society launched its Igor I. Sikorsky Human-Powered Helicopter Competition, only five such craft have managed to get off the ground.

Launching a helicopter