What are Airplane windows made up of?

 The windows of airplane are not made up of normal glass material but are made up of some special material called Stretched Acrylic named Polycarbonate substance which are not heavy in nature but are very stronger than the normal glasses that were used in Daily routine. The Glass of windows are made with number of layers in it which can not broken easily but if some one breaks the first layer of glass with the help of some sharp material than even he will not able to crack out the middle or other layer of Polycarbonate glass which are very stronger in nature. There is a hole in the middle layer of Polycarbonate glass for condensation.

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