What are the tiny holes in your airplane window for?

When you sit back and relax in your seat, you may notice a small round tiny hole in your window. Have you ever wondered what it’s for?

With the pressure outside the plane dropping as you get higher, the plane is designed to maintain air pressure at a safe level inside the cabin. The difference in their pressure puts a lot of physical stress on airplane windows. Thanks to the tiny hole in the middle pane, known as the ‘bleed hole’, it can balance air pressure. The hole allows pressure to balance between the passenger cabin and the outside world. The tiny hole also releases moisture. This prevents the window from fogging up and freezing.

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