It's the nature of an airplane to want to fly. Stripped of its jets, even a ponderous 747 is predisposed to glide for miles. Unlike the helicopter - kept aloft by the force of engines - a powerless airplane will sail like a well-tossed paper plate if given enough altitude. Such is the basis of soaring - a sport that matches willing pilots with the most eager of airplanes. The activity claims 20,000 participants in the United States - 100,000 worldwide - and is in the wind to become an Olympic sport in the coming decade.
``Power planes are pretty boring,'' said Eric Mozer, a world-class soaring pilot from Clover, S.C. ``I fly them, but they're for just in case you want to travel somewhere. If you want to fly for fun, soaring is the way to go. It's such a kick. Ninety percent of the people flying airplanes should be flying gliders, but they don't because they never learn about it.''
A sailplane has no motor, only the contour and composition to accept flight. Pilots are towed aloft by engine-powered planes and released. They stay airborne by searching for rising pockets of warm air called ``thermals'' that allow their plane to gain altitude and soar.
For purists, ``soaring'' is the act of gaining altitude and ``gliding'' is the act of gradual descent. Because early sailplanes were capable only of gliding, that term is more traditional and popularly recognized. Yet soaring is the more contemporary label.
In competition, pilots are given a course of travel called a ``task.'' The task, often 200 miles or more, is set the day of competition based on prevailing weather conditions.
Pilots set out to complete the task in the shortest time. The trick is to catch a thermal - follow the course - and catch another thermal en route to the finish. It becomes a game of Chinese checkers - often necessary for a pilot to make two moves sideways in order to make one forward.
``The challenge is to get something from nothing out of nature,'' said Doug Jacobs, a world-class flier from Larchmont, N.Y. ``A comparison to sailing sailboats is apt. Like sailing, you're out there on your own trying to outguess the elements. You're always so busy thinking, do I turn left? Right? Will I find lift over there, or should I go the other way?''
Pilots find thermals by watching for cumulus clouds. They may also find ``lift'' along the face of a mountain where deflected air moves up and over the mountainside, building a wave that carries the plane. Soaring hawks and eagles mark thermals as well, because those birds use rising warm air for their own flight. Perhaps surprisingly, common horizontal wind is not important to keeping a sailplane airborne.
And unlike auto or boat racing, soaring does not romance mechanical advantages. There aren't any. The planes are made of fiberglass and carbon fiber composites with an airplane's usual assortment of gauges. But there are no tricky wing adjustments to be made, or secret fuel formulas to gain an advantage.
About the only variable is the amount of water a pilot chooses to carry in the wings. In competitive planes, up to 400 pounds of water may be loaded there. The water is used for ballast to improve flying speed. But if soaring conditions grow weak, it can be dumped to allow the plane more ease in gaining altitude.
``You might improve your performance a percent or two by working real hard on the plane itself, but the difference that makes compared to the decisions you make as a pilot is no comparison,'' Jacobs said. ``Your decisionmaking could improve your performance 25 percent. Basically, everybody has equal equipment. It comes down to the pilot.''
Sailplanes fly at speeds as low as 45 m.p.h. between thermals, to more than 140 m.p.h. in a high-speed cruise. The world distance record is 1,016 miles and the world altitude record is 49,009 feet. At 12,000 feet or above, pilots breathe from oxygen tanks.
Sometimes, however, the relentless pull of gravity is too much and a pilot must ``land out'' - coming down far from the intended destination. It happens to everybody. Landing the plane is not usually a problem for an experienced pilot - it can be done on a softball field. The real problem is soothing an aching ego and finding a ride back home.
``It's really a statistical game,'' Jacobs said. ``You might shoot for the optimum statistical advantage in certain weather and push it a little bit. But if you push too far, it doesn't pay. You might win a couple of days, but you might land out. It's a risk-and-reward trade-off you're playing. It doesn't reward those that take too many risks.''
Soaring is relatively safe, largely because of the stability of the planes. If a pilot were to let go of all controls, the plane would reach some degree of status in the air of its own accord.
Moreover, a pilot who parachutes from a sailplane is likely to touch ground before the aircraft. That's because a common competitive sailplane has a glide ratio of 42-to-1, meaning from a height of one mile - in calm air - the plane will fly 42 miles before landing.
And despite the popular image of balsa wood and rubber band construction, sailplanes are not toys. They are built to withstand the stresses faced by a commercial airliner.
``I got into it because I wanted to choose a sport that had all the ingredients of auto racing, chess, and adventure,'' Mozer said. ``For me soaring was it. This is a sport I can do the rest of my life.
``When I see a bird up there at 14,000 feet, it's amazing. I'm sitting there breathing my own oxygen and here's this bird - I can't imagine what he's breathing. In what other sport can you be a part of something like that?''
Twenty of the world's top pilots gathered in Phoenix in May for the second Hitachi Masters of Soaring. Ingo Renner of Australia won the week-long competition and a $5,000 first prize from a $20,000 purse.
It was soaring's first big-money professional tournament and a signal that the sport may be flying from obscurity. A berth in the Olympics could be next.
``We're recognized by the International Olympic Committee as an Olympic sport,'' said Larry Sanderson, executive director of the Soaring Society of America in Hobbs, N.M. ``Now we have to get approval from the US Olympic Committee. It's about a year-and-a-half process, but it's not a matter of if ... it's a matter of when.''