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With its mix of Boeing and Buzz Lightyear, Yves Rossy’s "Rocketman” rig has brought worldwide attention to the obscure sport of wingsuit flying.

“It definitely got the world’s attention,” says Roy Haggard, a California-based aerospace engineer and entrepreneur. “People are amazed by it.”

Swiss adventurer Mr. Rossy last week was forced to abort an attempted record flight from Morocco to Spain when he flew into huge clouds that left him flying blind. He jettisoned his wings and parachuted safely into the ocean below. He was rescued a short time later.

“I am still here — a little bit wet but I am still here,” he told a news conference after a medical checkup. “I did my best."

Mr. Rossy’s suit uses existing technology in unexpected and innovative fashion. Most wingsuits are modified skydiving suits, with fabric flaps between the arms and legs that convert a jumper into a human flying squirrel. Mr. Rossy’s suit takes the concept to a new level by adding a carbon fiber wing and rocket engines that allow him to maintain level flight.

Like all wingsuit designers, Mr. Rossy was forced to balance a pair of contradictory demands: Fitting inside an airplane and jumping out of it calls for a small, flexible apparatus, but flying calls for a large, smooth wing that maximizes lift and minimizes aerodynamic drag. Because their span is limited to the length of a human arm, fabric wingsuits have limited performance - the best ones allow a jumper to glide at an angle of approximately 30 degrees.

Mr. Rossy’s design, on the other hand, spans nearly three metres, and it has much better glide performance. Although it’s large for a wingsuit, Mr. Rossy’s wing is still tiny compared with other wings designed to carry the weight of a human - a modern hang glider, for example, may have a wingspan of nearly 13 metres.

The key to efficiency is what’s known as aspect ratio - a long, narrow wing makes more lift and less drag than a short, deep one. A high aspect ratio wing, as on a high-performance sailplane, glides well but flies relatively slowly. A low aspect ratio wing, like that of an F-16 fighter jet, has poor glide performance and high landing speed, but allows superb maneuverability.

The small size makes Mr. Rossy’s wing behave more like a jet fighter than a glider - he typically cruises at more than 200 kilometres an hour, and he must land by deploying a parachute. Although it’s relatively small, Mr. Rossy’s wing is still large for a lightweight object that must be pushed out the door of an airplane into a powerful windblast. To solve this problem, Mr. Rossy’s wings fold, reducing their size. After he jumps from the aircraft, Mr. Rossy folds the wings down, then locks them into place with a mechanism similar to one used on airplane landing gear.

Although his carbon wings have made him a celebrity, Mr. Rossy was not the first wingsuit flier to try them. In 2003, Austrian Felix Baumgartner used a set of switchblade-style carbon airfoils to freefall across the English Channel. Unlike Mr. Rossy’s wing, Mr. Baumgartner’s had no engines.

The jet engines on Mr. Rossy’s wings are scaled-up versions of jets designed for model airplanes. To produce the thrust required for level flight and short climbs, Mr. Rossy uses four of them. One of the most difficult design challenges Mr. Rossy faced was starting the jets as he flew. (In a model aircraft, the engines are started on the ground with a portable power unit that spins them at high speed.)

Mr. Rossy overcame the problem by installing small compressed air tanks and fuel injectors.

Mr. Rossy is a highly qualified pilot - he flies for Swissair, and he was trained as an air force fighter pilot. He has also flown hang gliders, paragliders, and aerobatic light planes. But his Rocketman project took him into unknown territory. He controls the jet engines with a hand-held throttle, and steers by moving his head and legs, which shifts his weight and alters the airflow over his wings. During test flights, Mr. Rossy was forced to cut away from the wing and parachute to safety six times after it went into unrecoverable spins.

Although he has refined the design and mastered flying it, Mr. Rossy still faces serious risks. Among them is disorientation. Unlike the airliners he flies for a living, his Rocketman suit has no flight instruments that can tell Mr. Rossy whether he’s right side up or not, so he depends on seeing the ground for orientation.

Financing his latest project presented Mr. Rossy with one of his greatest challenges: “When you go to an investor and say you need $80,000 to fly with a wing on your back with jets on it, the guy looks at you and takes you as a crazy guy,” he said.