Have you ever wondered why most of the planes you see are white ? Why it's not likely to encounter a colored airplane? The reasons are scientific and economics. 

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Thermal Science !

An MIT professor in  Aeronautics and Astronautics said that white is the best color to reflect sunlight and keep the internal of the plane cool, but the most important is to protect the plastic parts of the plane from heat. Beside that, the white painting of the plane could protect it from dangerous solar radiation too.

The white color on an airplane is appreciated by birds and researches have shown that birds will experience less collision if planes are painted with white compared to other colors like blue, and it will help humans visually.

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Economics

It takes approximately 65 gallons of paint for one airplane, so airlines would search for a cheap way to paint their planes, and the best solution is white painting. White is a standard color and cheap, it is not the only cause to choose white, there is a bigger one, whatever color you will choose to paint your airplane it will oxidize over time and the color will fade leaving a white airplane so in order to keep it's color you will have to paint your plane more frequently and that will cost you more money