Last summer the Solar Challenger, a one-person plane fueled entirely by sunlight, flew the English Channel. The milestonemaker now hangs in the Air and Space Museum, where the Gossamer Condor is already installed, an earlier invention by the same team led by Paul MacCready. Their Condor was powered by the pilot's legs.

The Solar Challenger looks like a giant wasp, or an experimental fly that got out of hand, and it isn't too practical: the maximum airspeed was 47 mph on the 230-mile flight, which took five hours and 23 minutes.

In Greek mythology, the problem with the flight of Icarus was too much sun, when his waxed-on wings melted off; the Solar Challenger can suffer from too little. Since the plane uses no storage batteries, it loses altitude when flying under clouds and turns off at sunset. "You're always above a potential landing area," says Ray Morgan, of the MacCready team. But, Morgan says, as a glider, the airplane sinks at a rate that gives a pilot enough time to slip out from under could cover. Unlike Icarus; the plane gathers strength as it nears the sun; it can reach 50,000 feet, as long as the pilot wears breathing apparatus and warm clothes.

The Challenger is quite an example of Yankee ingenuity. MacCready believes he succeeded because he didn't know much about aircraft design. He did what was logical, instead of making it look like an airplane, which "was not the right structural technique for this particular task," he said.

the Challenger weighs a mere 217 pounds, and like a jockey before the big race, the pilot, Stephen Ptacek, lost 25 pounds for the international run. He weighs 127. SOLAR CHALLANGER--At the National Air and Space Museum through Labor Day. %SOLAR CHALLANGER--At the National Air and Space Museum through Labor Day.