History of Soviet Gliders. (Soviet Union, USSR 1983)

Stamp History of Soviet Gliders. it reflects the thematic directions:

A glider or sailplane is a type of glider aircraft used in the leisure activity and sport of gliding (also called soaring). This unpowered aircraft can use naturally occurring currents of rising air in the atmosphere to gain altitude. Sailplanes are aerodynamically streamlined and so can fly a significant distance forward for a small decrease in altitude.

Aviation is the practical aspect or art of aeronautics, being the design, development, production, operation and use of aircraft, especially heavier than air aircraft. The word aviation was coined by French writer and former naval officer Gabriel La Landelle in 1863, from the verb avier (synonymous flying), itself derived from the Latin word avis ("bird") and the suffix -ation.