Bangladesh Air Force Operation Kilo, 50th Anniversary (Bangladesh 2020)

Souvenir Sheet Bangladesh Air Force Operation Kilo, 50th Anniversary it reflects the thematic directions:

An air force, also known in some countries as an aerospace force or air army, is in the broadest sense, the national military branch that primarily conducts aerial warfare. More specifically, it is the branch of a nation's armed services that is responsible for aerial warfare as distinct from an army, navy, or a marine corps. Typically, air forces are responsible for gaining control of the air, carrying out strategic and tactical bombing missions, and providing support to land and naval forces.

The term "air force" may also refer to a tactical air force or numbered air force, which is an operational formation either within a national air force or comprising several air components from allied nations. Air forces typically consist of a combination of fighters, bombers, helicopters, transport planes and other aircraft.

Many air forces are also responsible for operations of the military space, intercontinental ballistic missiles (ICBM), and communications equipment. Some air forces may command and control other air defence assets such as anti-aircraft artillery, surface-to-air missiles, or anti-ballistic missile warning networks and defensive systems. Some nations, principally Russia, the former Soviet Union and countries who modelled their militaries along Soviet lines, have or had an air defence force which is organizationally separate from their air force.

Peace-time/non-wartime activities of air forces may include air policing and air-sea rescue.

Air forces are not just composed of pilots, but also rely on a significant amount of support from other personnel to operate. Logistics, security, intelligence, special operations, cyber space support, maintenance, weapons loaders, and many other specialties are required by all air forces.

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."

A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of short take-off and landing (STOL) or short take-off and vertical landing (STOVL) aircraft cannot perform without a runway.