When the plane takes off, the booster in the plane will inflate, which will increase the atmospheric pressure in the cabin. When the plane climbs, it will reach the height limit that the human body can bear the normal air pressure. Then, the pressurization device will supplement and adjust the pressure environment faced by the plane when it rises, so that the whole cabin will always maintain the normal air pressure within the range that the human body can bear.

Without pressurization, passengers will expand in an instant, suffocate due to oxygen leakage in the cabin and gradually lose consciousness. If there is not enough oxygen supply, the final result is that all of them die of lack of oxygen.

Extended data

The increased air pressure should meet the human body's demand for oxygen content in the air, and the ventilation can be adjusted to make the temperature and humidity meet the physiological needs, so that passengers can have a comfortable and safe living environment during high-altitude flight. 6000？ Aircraft flying within 24000m must use a pressurized cabin, and the pressurization value in the cabin is usually 50? 60kPa atmospheric pressure, cabin temperature control in 15? 20 tons.

Aircraft with flight stiffness over 24000m (except a few aircraft, mainly spacecraft) cannot use atmospheric pressure compression chamber due to low air density, but use regenerative compression chamber with its own air source or regenerative gas source.

Modern aircraft mostly adopt integral supercharged cabin. In order to ensure air tightness, the movable parts such as doors and windows are usually sealed with rubber pads or rubber pipes, and the fixed connection parts are connected by air-tight bolts and air-tight interference riveting.

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