I heard that some airplanes don't have engines. how many airplanes in the world have engines?
closed as too broad by fooot, bogl, Ralph J, David Richerby, SMS von der Tann Jan 15 at 22:55
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All airplanes have engines, the definition of an airplane (or aeroplane) is:
A powered flying vehicle with fixed wings and a weight greater than that of the air it displaces.
There are aircraft that do not have engines, for instance gliders.