H
ave you ever dreamed you could fl y like
a super hero? What if you could actually soar through the air, glide over tree-topped hillsides, and dive through puff y clouds? T e idea of fl ying is nothing new. For the
past 2,000 years, inventors have designed inventions for fl ight. T ey have made huge kites to liſt people off the ground. T ey have made wings for people to wear. Today, people continue to invent ways to take to the skies. Technology gives us tools, materials, and
know-how to think of new ways to become airborne. Some ideas mimic birds and other fl ying animals. Other plans reuse old ideas. Some new ideas seem like they come right out of the future. Let’s explore some of the suits and machines that make this dream of fl ying a reality.
Gliding Through the Air First-time fl yers and experienced pilots oſt en use the word “peaceful” to describe hang gliding. Hang gliders have no engines, so fl ying in one is very quiet. Like birds’ wings, hang gliders take
advantage of a wing’s ability to create liſt . Liſt is a force. It opposes gravity. Gravity is the force that causes objects to fall toward the center of Earth. To be able to fl y, a machine’s liſt must be greater than gravity. A hang glider launches from the ground.
T e pilot straps on the 30-kilogram hang glider frame. It’s made from a light-weight aluminum. It has a wing-shaped sail made of high-tech fabric on top of the frame. T e pilot sprints down the side of a steep
hill. Gravity pulls the glider forward as the pilot runs into the wind. T e sail catches the air and liſt s the pilot up. If the pilot runs fast enough, liſt overcomes
both gravity and drag. Drag is a force that slows things down. Running into a wind can slow a pilot down. If all the conditions are right, a pilot’s feet will leave the ground. T en the glider and pilot soar into the air.
12 NATIONAL GEOGRAPHIC EXPLORER
Once in the air, the pilot tucks his or her legs
into a fabric bag that hangs below the frame. Keeping the legs together in one place helps reduce drag while in the air. Hang gliders have controls to change their
speed and direction. A bar hangs within arm’s reach. T e pilot moves it to change the angle of the wing. Pushing the control bar forward slows the glider down. Pulling the control bar back drops the nose of the glider and increases its speed. To change direction, the pilot shiſt s his or her weight to the right or leſt . Rising warm air from Earth’s surface creates
winds that keep hang gliders aloſt . Experienced pilots can stay in the air for hours and travel great distances. Cliff s along coastlines are a favorite location for pilots to fl y. T e cliff s force the air moving in from the ocean upward. T ese winds push upward on the wing. When the pilot is ready to land, he or she adjusts the angle of the wing. When the glider is near the ground, the pilot gets ready for a running stop.
A hang glider uses winds to create lift.
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