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.