Why do airplane windows have tiny holes: the answer from experts
Looking out of an airplane window during a flight is quite thrilling, and unless you're a pilot or flight attendant, it's probably not an everyday experience to see clouds, mountains, or cities from a bird's-eye view. Have you ever wondered about the kind of pressure exerted on the window glass that separates you from the endless sky?
Fortunately, engineers who design airplanes take all these physics-related issues into account to make airplanes a very safe mode of transportation. That's why you may notice a tiny hole in every airplane window. This opening, known as a vent, is an important design element because it helps regulate air pressure, according to Travel+Leisure.
Air pressure and the amount of oxygen in the air decrease the higher you go above sea level. And low air pressure and limited oxygen are not ideal for humans. That's why airplanes are pressurized - to keep us alive and comfortable throughout the journey.
"When an airplane gains altitude during a flight, the air pressure in the cabin drops. However, airplanes are designed to maintain a safe cabin air pressure for passenger comfort. As a result, during the flight, the air pressure outside the aircraft is much lower than inside," says an Airbus representative in an interview with Travel + Leisure.
Perhaps it is not surprising that windows are a weak point of airplanes - they are made of acrylic, which is not as strong as various metals or composite materials used to make the fuselage. However, passengers probably won't like flying in airplanes without windows, and having an external view in an emergency is crucial for evacuation. Therefore, instead of completely abandoning windows, they are designed to be as strong as possible.
Windows in airplanes are round because pressure is more evenly distributed over a rounded shape. In addition, there is an air vent that is designed to help reduce the pressure exerted on the window.
"An airplane window is actually made up of three panels: an outer panel that handles the difference in air pressure; a middle panel with a vent, a tiny hole that helps balance the air pressure; and a thin inner panel, also called a protective panel, that helps protect the middle and outer panels from damage in the cabin," says an Airbus spokesperson. The vent helps to balance the air pressure between the outer and middle panels. It also releases moisture from the space between the panels, preventing fogging or icing.
So the next time you take a picture out of an airplane window, you can thank this little hole for keeping the acrylic as clear as possible and keeping you in one piece.