Hang gliding is a popular American sport today. A hang glider looks something like a huge kite. It is shaped like a triangle. At its widest point, a glider is about as wide as the length of a car. The flier wears a harness attached to a glider. He holds onto the glider and races down a hill into the wind or else jumps off a cliff. The wind lifts the glider into the air. The pilot uses a control bar to change the directions. A hang glider is made with Dacron sails and aluminium frames. Some other gliders are made from rigid materials such as wood and glass fiber.
A hang glider usually travels as fast as a car on a busy street. A person learning to hang glide usually flies 3 to 6 metres above the earth. A trained pilot might go much higher. They sometimes carry equipments like maps, compasses, parachutes, radios etc. Pilots flying over mountainous areas often carry oxygen. The hang gliders never fly as high as airplanes.
Though many people have contributed to the development of the glider, the pioneer was a German, Otto Lilienthal (1848-96). Along with his brother Gustav, he began experimenting in this direction in 1867 on the buoyancy and resistance of air. After a lot of experiments he succeeded in 1891 in making his first man-carrying craft, with which he could take off by running downhill into the wind. He made numerous flights between 1893 and 1896.
This was the beginning after which many developments were made in the design of gliders by Octave Chanute — a French-born American Engineer, Orville and Wilbur Wright etc. In the 1950s Professor Francis Rogallo of the National Space Agency, USA, relying on his space capsule re-entry researches, developed a wing.
In the case of most of the early gliders the flying speed was very low. The normal practice was to fly into a wind so that the actual acceleration required was not too much. These days the favoured launching techniques are the airplane tow and automobile tow. The tow rope is usually 60 metres long with a steel ring attached at each end, fitting the tow hooks with the towing vehicle and the glider.
Many records of long distance gliding and of greatest altitude gliding have been set in the world. Heights of 10,000 ft have been attained by some hang gliding pilots flying in mountainous areas. Since 1935 hang gliding has earned a reputation as tools for aeronautical and meteorological research.