The biggest fear among the passengers seated near the emergency door is whether the door can be opened from the inside. The answer is a definite no unless a passenger can gather the strength of around 20,000 pounds to open the emergency door.
However, there have been instances when passengers have tried to open the emergency exit door either because one of them was curious without realising the consequences of his action or because he was mentally ill. In one case last year, a woman reportedly had a “mental breakdown” and tried to open the aircraft door to get out on a flight from Texas to North Carolina. The cabin crew rushed towards the lady and managed to duct-tape her to her seat.
Let us find out the reason for not being able to open the emergency exit door during a flight. Patrick Smith, who writes the blog askthepilot, asks the readers to visualise an aeroplane door as a drain plug held by the pressure within the aircraft. The doors to almost all of the exits on board aircraft open inward.
Cabin pressure
At an average cruising altitude, approximately eight pounds of pressure is exerted against every square inch of the inner fuselage. That’s nearly eleven hundred pounds of pressure pressing against the door in every square foot. Even at low altitudes, the pressure inside the cabin is far lower, a meagre two pounds per square inch. The difference is still more than what can be accomplished by anyone. Hence, the doors cannot be opened unless the aeroplane is on the ground. Even to do that, the cabin crew must do a sideways shuffle because the door is effectively plugged into a hole.
Now that we know that human beings cannot open emergency doors while on a flight, the windows are usually the aircraft’s weak spot. So, it is recommended to wear the seat belt even when the seat belt indicator is off.
Source: aircrafttechnic.com, highskyflying.com, askthepilot