are there any other sports related to it?
Yes, hang gliding and paragliding.
Gliding
The two air sports that are most closely related to gliding are hang gliding and paragliding. 
how long do gliders stay in the air Glider pilots can stay airborne for hours by flying through air that is ascending as fast or faster than the glider itself is descending, thus gaining potential energy. is it a sport? Yes, a competitive air sport. how is it done? Pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. does it face any challenges? UNANSWERABLE are there any competitions of it held? Local and national competitions along with biennial World Championships. what is the championship mentioned about? It is a gliding competition held every two years or so. who organizes it? The FAI Gliding Commission. when was it founded? The Commission was founded in 1932. does it present any awards? The Commission makes awards for great achievements and meritorious service. Eg- The Lilienthal Medal.
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Gliding [SEP] Related air sports
The two air sports that are most closely related to gliding are hang gliding and paragliding. Although all three sports rely on rising air, there are significant differences which are listed in detail in . The main difference is that both hang gliders and paragliders are simpler, less sophisticated and cheaper aircraft that use the pilot's feet as the undercarriage. All paragliders and most hang gliders have no protective structure around the pilot. However, the dividing line between basic gliders and sophisticated hang-gliders is becoming less distinct. For example, hang gliders typically use fabric wings, shaped over a framework, but hang gliders with rigid wings and three-axis controls are also available.