27 May (Angola ) within release Travel of the President Francisco H.C. Lopes to Angola goes into circulation Stamp Map of Angola face value 35 Angolan centavo
Stamp Map of Angola in catalogues | |
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Michel: | Mi:AO 390 |
Stamp Number: | Sn:AO 383 |
Stamp is square format.
Also in the issue Travel of the President Francisco H.C. Lopes to Angola:
Stamp Map of Angola it reflects the thematic directions:
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.
An aircraft is a machine that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. The human activity that surrounds aircraft is called aviation. Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others.