Do unpainted plane be more efficient?

You have always seen planes with vibrant colours, have you ever seen a airplane with just aluminium body without any paint ???

Probably not !!!!!! Ever asked yourself why !!!

Simply colouring the plane, makes plane gain more weight. Yes they add a huge weight.

More is the weight, less in the fuel efficient. Then why they can't leave the body unpainted ??

You may be thinking of paint as a thin film over a substrate.So the obvious question will be how much could a thin film should weigh?

In fact in plane, they use paints by the barrel, which is very heavy in weight.

Ok, if you ll not use the paint and keep the body uncolored, its ok. But you need some protection.

Image source

The way iron develops rust or ferric oxide, aluminium develops aluminium oxide, if un protected then it may get damaged due to deposit of aluminium oxide on its surface.

So in order to protect the surface, you have to continuously protect it by polishing and applying the wax in recurring interval.

But maintaining frequently with wax and polishing is very cost effective,as it requires labour and recurring material too.

Finally its a call of the owner to take a decision.