The cinema has created a fantasy that haunts those who fear to fly: at 11,000 meters above sea level, one of the doors of the plane is opened by accident or by the action of a passenger during an oversight by the crew. If that happened, the cabin would undergo a violent decompression capable of sucking in anyone who was not securely attached to the seat , and even those who were but had the misfortune to travel too close to the door.
In a commercial flight it is impossible to open the doors, because they move only inwards. The difference in pressure with the outside is such that to open them it would take a force equivalent to that necessary to lift a ton with the arms . Before take-off, the doors enter the apparatus at an angle and are then fastened to the frame; During the flight they work as a plug that keeps the air inside.
The only time to open a door – or for that to happen accidentally if it is not properly secured – is during takeoff and landing, when the external and internal pressure are similar. If it happened, which is highly unlikely, the passage would only notice it by the deafening noise of the engines. The pilot would see on his control panel the indication that the door is open and would abort takeoff or land the aircraft if it was already in the air.
Some specially designed aircraft, such as certain military models or those commonly used by paratroopers, are a special case. These often do not have pressurized cabins because they fly much lower than those of commercial airlines. That is why it is possible to open the doors in the air without difficulty or danger.
Image: Daniel J. McLain / US Navy
