Why does the plane window have a small hole?

The small hole in the airplane window helps maintain the air pressure at a safe level inside the cabin, while escaping the steam so the window is not dimmed.

Unpredictable chopsticks head hole on the plane

The small hole plays a big role

If you've ever been on a plane, you'll probably notice a small hole on the bottom edge of the window . This seemingly simple detail has a duty to balance the pressure in the aircraft.

When you look carefully at the window, you will discover that the window glass is made up of 3 separate layers, usually made of acrylic material . The purpose of the clear acrylic layer is to protect the two outer layers.

The hole is small but plays an important role on the airplane window.(Photo: BI)

As the plane rises, the air pressure decreases. The external air pressure is much lower than inside the aircraft, causing many harmful physical impacts to the airplane window. The pressure balance system inside the aircraft will adjust the pressure inside the aircraft at a safe and comfortable level for passengers.

The acrylic layer in the middle and the outer part of the aircraft window will have to bear the force due to the differential pressure. Both of these layers can withstand the pressure of pressure , but thanks to the small hole in the window, only the outer layer must bear the force.

Important factor

Marlowe Moncur, chief technology officer at GKN Aerospace, said: "The purpose of the small breathing hole on the middle plate is to balance the pressure inside the passenger compartment and the gap between the acrylic plates, so the pressure is The passenger compartment will only affect the outermost plate. "

In the event that the outer acrylic sheet cannot withstand the pressure (almost never happens) and cracks, the middle plate will replace the outer plate. Of course, the small hole in the middle plate will allow a small airflow to pass through, but the pressure balancing system will solve the remaining problem.

Looking at the hole seems simple, but it really isn't.(Photo: BI)

Bret Jensen, a senior aviation technician from Boeing, said: 'This hole helps prevent moisture and snow from clogging on the window. This explains why your windows are not dimmed every time the plane passes through the clouds. "

During long flights, a thin layer of snow can accumulate in the area around the breathing hole. Because many flights can reach a height where the air outside can drop at -57 degrees Celsius.

The video explains why the plane always has small holes in the window.