Flight

Flight is the process by which an object moves, through an atmosphere or beyond it, as in the case of spaceflight. This can be achieved by generating aerodynamic lift, propulsive thrust, aerostatically using buoyancy, or by ballistic movement.

Many things fly, from natural aviators such as birds, bats and insects to human inventions such as missiles, aircraft such as airplanes, helicopters and balloons, to rockets such as spacecraft.

The engineering aspects of flight are the purview of aerospace engineering which is subdivided into aeronautics, the study of vehicles that travel through the air, and astronautics, the study of vehicles that travel through space, and in ballistics, the study of the flight of projectiles.

Humans have managed to construct lighter than air vehicles that raise off the ground and fly, due to their buoyancy in air.

An aerostat is a system that remains aloft primarily through the use of buoyancy to give an aircraft the same overall density as air. Aerostats include free balloons, airships, and moored balloons. An aerostat's main structural component is its , a lightweight skin that encloses a volume of lifting gas to provide buoyancy, to which other components are attached.

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