Why are plane windows round?

Answer 1

to prevent stress fractures in the fuselage eventually resulting in explosive decompression...square windows were used at first, but many airplanes crashed because of their leading to cracks in the planes (best ex. De Havilland Comet)...round windows are stronger due to their shape and do not transfer stress to the fuselage

Answer 2

Square windows can cause stress points at any of the four corners of the window .In due time in a pressurized cabin fatigue will cause cracks to develop at these stress points. This was a problem with the first jet passenger plane of Great Britain. Round windows have no concentrated stress points

Answer 3

Back at the beginning they were not round. Plane windows are round to avoid cracks at the corner of them. Pressurized aircraft stresses the body every time they go up. This was learned the hard way when 2 passenger planes ripped in the sky due airframe fracture at the corner of the windows.

Answer 4

Some good answers but alot of wrong ones too. not all aircraft windows are round. You will notice that smaller aircraft do not have round windows. This is because they do not need to be round. Airliners and smaller turbo-prop aircraft have round windows because they are pressurized. Some aircraft a while back did not have the round windows and due to the pressurization system cracks started to form and the aircraft "fell out of the sky". So this easiest way to say it is, they are round because it is stronger.

Answer 5

It's all due to the greater ability of round windows to more evenly distribute the stresses of pressurized cabins. Also square corners tend to set up stress risers in the adjacent metal causing cracking and ultimately failure. If the windows are not round, they will at least have rounded corners for the same reason.

Answer 6

anytime you have sharp corners when dealing with high pressures, you get locally high stress points which could cause metal failure. So you put a rounded edge on the window frame to help lower the stress.

Answer 7

Because the fuselage cracked and planes fell out of the sky in the 1950's when jetliners were first in service ( DeHavilland Comet?)
It was traced to the 'square' windows so they make them round to avoid stress cracking of skin. Its cold at 35,000ft (minus 40 or so)

Answer 8

They're not. They're usually rectangular. The corners are rounded to minimize stress at the corners. Sharp angles are much more susceptible to stress cracking than rounded ones.

Answer 9

for strength, the square ones were on a british airliner and the weakoned and led to alot of crashes.

Answer 10

Y is the sky Blue? Y is the grass Green? Y is Bush President still? Y am I so Damn beautiful. Because the Architecture Who designed the plane likes round objects because if he made them square it would be like in a car . And if he made them triangular not everybody could see out them completely. Now Y am I so beautiful? .. Blame God .. He did it to teach me a lesson..