when?
In  the 1920s and 1930s
Gliding
Thus, in the 1920s and 1930s, while aviators and aircraft makers in the rest of the world were working to improve the performance of powered aircraft, the Germans were designing, developing and flying ever more efficient gliders and discovering ways of using the natural forces in the atmosphere to make them fly farther and faster.
how long do gliders stay in the air They can stay airborne for several hours. what is gliding? It is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. who created the first glider? The Germans
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Gliding [SEP] History
The development of heavier-than-air flight in the half century between Sir George Cayley's coachman in 1853 and the Wright brothers in 1903 mainly involved gliders (see History of aviation). However, the sport of gliding only emerged after the First World War, as a result of the Treaty of Versailles, which imposed severe restrictions on the manufacture and use of single-seat powered aircraft in Germany's Weimar Republic. Thus, in the 1920s and 1930s, while aviators and aircraft makers in the rest of the world were working to improve the performance of powered aircraft, the Germans were designing, developing and flying ever more efficient gliders and discovering ways of using the natural forces in the atmosphere to make them fly farther and faster.