Flight Of Fancy.(FanWing, fan-powered aircraft)

Even its creator doesn't give the FanWing high marks for elegance. The balsa-wood models of this would-be flying machine of the future that litter Patrick Peebles's farmhouse near Rome have the look of aeronautic freaks. Consider the basic design. The wing isn't shaped in the familiar tapered curve, but rather more like a long cylinder fitted with outsize rotor blades. (Earlier prototypes were weirder still: one that resembled a flying paddle-wheeler never managed to leave the ground.) Peebles, an American with a passion for the home-invention business, is frank: "It looks like an old push-mower or a combine harvester. It shouldn't fly--but it does."

And that's some achievement. Whatever its appearance, the FanWing is something of a rare event in the aeronautics world: a wholly new technology of flight. The ungainly creature that Peebles, 57, has worked on for much of the past decade combines many of the best features of helicopters and traditional fixed-wing airplanes. It uses far less fuel than a helicopter or a conventional airplane and needs little or no space for takeoff and landing. It is quieter than a helicopter and would cost far less to build and operate. Given a little more time and development money, the FanWing might claim a new niche in aviation: that of a low-cost, slow-moving workhorse of the skies. The potential, at least, is huge. The British government has already coughed up some money to test the vehicle. "My drive to innovation is just a desire to do things differently," says Peebles. "It's fun--and this time the fun has spawned something useful."

The FanWing is certainly different. In a conventional airplane, propellers or jet engines provide only the forward drive, while the movement of the plane's wings through the air supplies the lift. In the FanWing, spiral rotor blades, which revolve like the blades of an old- fashioned push lawn mower, run the length of each wing. By pushing a big volume of air over the top of the wings, the blades create lift even before the vehicle is moving. They also act as giant propellers, propelling the FanWing forward. "We just grab the air all the way along the front of the wing and give it a push over the top," says Peebles. The difference doesn't sound like much, but it makes for a stable ride, little noise and high fuel efficiency. And it doesn't require the hugely complicated and sensitive mechanical gizmos that go into keeping a helicopter aloft. "Essentially all this needs to fly is a single rotor in each wing," says Peebles.

What's more, its peculiar design means the FanWing will never stall: as its speed falls, the lift only declines gently, rather than abruptly as on an airplane. For a conventional aircraft just a tiny shift in the angle of the air hitting the wing has big effects on lift, causing rough flights and sick passengers. But the FanWing, because of the small surface area of its wings, isn't as vulnerable to heavy winds. Peebles has managed to find an aeronautical solution that's eluded three generations of engineers out to create their own helicopter- airplane hybrids. "The fact is that it works," says Mike Graham, head of aeronautics at Imperial College, London, where promising air-tunnel tests were recently completed. "People had often talked about similar techniques, but I had never seen anyone succeed."

So far Peebles has ...