I bet you have noticed that airplane windows are mostly circular. But have you ever asked yourself why?

The design is strategic and aesthetic has nothing to do with it.

Circular windows were adopted for planes after two consecutive accidents in 1953 which killed 56 people. The cause of the accident was attributed to the windows, which were square in shape.

Engineers deduced that since the airplane technology had been upgraded to fly on higher altitudes where the air density was lower, the cabin was also changed to a cylindrical shape to support the internal pressure.

For this to work well the windows had to be adjusted to circular in order to balance the outward and inner pressure.

The engineers mentioned that the corners of squares windows were weak spots. “Four corners would be four potential weak spots, making the birds likely to crash under stress – such as air pressure”.

So there you go, next time you are in an airplane you will probably look at the window with a new perspective. Safety.