You’ve flown often, but you might not know it!

You’re sitting by a window, admiring the clouds, when a detail catches your eye: a small hole at the bottom of the glass. Is it just a curiosity or an essential feature? In reality, this small hole plays a vital role in passenger safety and comfort.
Why do airplane windows have holes?

When an aircraft reaches high altitudes, the outside atmospheric pressure drops considerably. Meanwhile, the cabin interior remains pressurized to ensure passenger comfort and safety. This pressure difference puts enormous stress on the windows.

This is where the famous “purge hole” comes in:

Pressure regulation: This vent equalizes the pressure between the cabin and the space between the central and outer panes of glass. Thus, only the outer pane bears the full pressure, while the central pane acts as a safety reinforcement. Fog prevention
: It allows moisture in this space to escape, preventing fogging. The result? A clear view throughout the flight.
A three-layer design for maximum safety:
Aircraft windows are not made of a single pane of glass but of three layers, each with a specific function: