František Běhounek, Explorer (Czech Republic 2023)

Souvenir Sheet František Běhounek, Explorer it reflects the thematic directions:

An aircraft (pl. aircraft) is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or the dynamic lift of an airfoil, or, in a few cases, direct downward thrust from its engines. Common examples of aircraft include airplanes, rotorcraft (including helicopters), airships (including blimps), gliders, paramotors, and hot air balloons.Part 1 (Definitions and Abbreviations) of Subchapter A of Chapter I of Title 14 of the U. S. Code of Federal Regulations states that aircraft "means a device that is used or intended to be used for flight in the air."

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.

Exploration is the process of exploring, an activity which has some expectation of discovery. Organised exploration is largely a human activity, but exploratory activity is common to most organisms capable of directed locomotion and the ability to learn, and has been described in, amongst others, social insects foraging behaviour, where feedback from returning individuals affects the activity of other members of the group

Famous People refers to the fame and public attention accorded by the mass media to individuals or groups or, occasionally, animals, but is usually applied to the persons or groups of people (celebrity couples, families, etc.) themselves who receive such a status of fame and attention. Celebrity status is often associated with wealth (commonly referred to as fame and fortune), while fame often provides opportunities to make money.