We all like to sit next to the window but did you ever think that why are airplane windows are round ?
Air transport became very popular in the 20th century. Therefore, almost all the airplanes flew at a higher altitude. When an airplane flies at higher altitude, it decreases the air density. Because of the low air density air resistance also decreases . In this case, it is very important to keep the internal air pressure at a higher level. Therefore, all aircraft are designed as cylindrical.
In the early years, aircraft windows are designed to square shape. Unfortunately, it has caused many negative effects.
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