| Riassunto: | Glider aircraft are heavier-than-air craft that are supported in flight by the dynamic reaction of the air against their lifting surfaces, and whose free flight does not depend on an engine. Mostly these types of aircraft are intended for routine operation without engines, though engine failure can force other types of aircraft to glide. Some gliders have engines for extending their flights and some have engines powerful enough to launch. There are a wide variety of types differing in the construction of their wings, aerodynamic efficiency, location of the pilot and controls Some may have power-plants to take off and/or extend flight Some are designed simply to descend, but the most common varieties exploit meteorological phenomena to maintain or even gain height Gliders are mainly used for the air sports of gliding, hang gliding and paragliding but are also used for recovering spacecraft. Perhaps the most familiar type is the paper plane. Early pre-modern accounts of flight are in most cases sketchy and it is unclear whether each craft was a glider, kite or parachute and to what degree they were truly controllable. Often the event is only recorded at a great time interval after it allegedly took place A historian, 17th century account reports an attempt at fhight by the 9th century poet Abbas Ibn Firmas near Conds Spain which ended in heavy back injuries. The monk Eilmer of Malmesbury is reported by William of Malmesbury (c. 1080-1143) , a fellow monk and have flows off the roof of his Abbey in Malmesbury, England, sometime betwees 1000 and 1010 AD, gliding about 200 meters (220 yd) before crashing and breaking his legs. Going by the sketchy sports, both used a set of (feathery) wings both based their crash on the lack of a tail
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