sentences:  Gliders are classified by the FAI for competitions into glider competition classes mainly on the basis of span and flaps.Unlike a sailplane, a hang glider is capable of being carried, foot launched and landed solely by the use of the pilot's legs.In a hang glider the shape of the wing is determined by a structure, and it is this that distinguishes them from the other main type of foot-launched aircraft, paragliders, technically Class 3.