Defination of an Aircraft.

A machine or device, such as an airplane, helicopter, glider,etc. that is capable of atmospheric flight.

In Engineering it is defined as,"Any machine capable of flying by means of buoyancy or aerodynamic forces, such as a glider, helicopter, or aeroplane."

Any vehicle which carries one or more persons and which navigates through the air. The two main classifications of aircraft are lighter than air and heavier than air.The term lighter than air is applied to all aircraft which sustain their weight by displacing an equal weight of air, for example, blimps and dirigibles.Heavier than air craft are supported by giving the surrounding air a momentum in the downward direction equal to the weight of the aircraft.

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