Earth's Curvature From Your Airplane Window?

Earth's Curvature Visible from your Airplane Window?



When confronted with the question of the shape of the world, many people are quick to assert that they live on a globe because they believe they have personally seen the curvature of the Earth from their airplane window. Some people even believe when they visit the beach or climb atop a mountain that they are able to see the horizon curve downwards far in the distance. The reality is, however, that anyone thinking they can see curvature on the horizon from any altitude is suffering from a serious case of confirmation bias and cognitive dissonance.

To begin with, the glass used in all commercial airplane passenger windows is actually round, layered and slightly curved which distorts the edges giving the impression that the horizon and other straight lines curve downwards. These rounded windows have the effect of evenly distributing pressure and reducing the likelihood of cracks or breaks because they have no corners for stress to concentrate making them better at withstanding pressure. Unfortunately though, these windows also have the strange side-effect of causing people to believe that the Earth is a globe because they mistake the curvature of the glass for that of the horizon...