Can the doors of an airplane really be opened while the plane is in the air? I would hope that they were locked and it would at least take an act of the pilot to unlock them.
I’d hate to think any idiot could get up and jokingly pull the handle and open the doors.
They should be locked, and even if they weren’t, the pressure difference prevents anyone from opening them at altitude.
However, there have been incidents in unpressurized planes, or in planes that were not at a high enough altitude, where a nut did manage to open a door or even to jump out.
The doors open inwards, so let's assume that you have a door that is 24" x 48" (an airplane door is a bit bigger) you would have 1,152 sq inches of surface area. Now if there is just a 1 PSI difference between inside and outside (inside being higher of course), then you would need to exert 1,152 pounds of force on the door to get it to move inward. This is one of the factors that led to the deaths in Apollo 1, they had an inward opening door and were conducting the test with 19.7 PSI or so and it would have taken an elephant standing on the door to get it to open.
At cruising altitude (39,000' or so) the difference between inside and outside is over 8 PSI. So going back to the 24" x 48" with 1,152 sq inches, it would take over 4 tons of force to open the door inward. Muhammed himself couldn't pull that off.
if you pay attention the next time you are on a plane, you will notice that in order to open a door, they must first pull it in and then push it out to open. This would take strength on the order of the Incredible Hulk to do at altitude since you would be pulling towards the high pressure side of the door. remember that pressure is measured in pounds per square inch. A typical arliner door is roughly 6’ (72”) tall by 2’ (24”) wide - maybe wider. This gives us 1,728 square inches of surface are over which the psi diff must be calculated. I don’t remember off hand the exact pressure difference between a pressurized cabin (pressurized to the equivalent of 8,000’ altitude) and the outside pressure at 30,000 ft altitude, but it’s in the 5-10 psi range. Even if it’s only a 5psi difference, He would need to pull the door inwards with a force of 8,640 lbs.
Do you think a human being could do that? Only an enraged Bruce Banner could do it, IMHO...
I was assigned an exit row seat one time and the flight attendant asked me (before take off) if I understood how to open the door in an emergency. I said “Don’t you just go like this?” while reaching toward the handle (I was just going to pantomime), and she got a little excited, so I’m guessing there is no electical lock on it.