With the recent spate of news stories about inflight incidents involving unruly passengers, you may wonder if it is indeed possible to open the door of an airliner in flight. Well rest assured, not only is that feat physically impossible, but in today’s highly aware passenger cabin environment, a troubled individual would have a very hard time even getting to the door handle without being seriously challenged by other passengers on board. Technically, an airliner’s door cannot be opened in flight for two reasons. First, cabin altitude during cruise is approximately 8,000 feet above mean sea level, with the cabin pressurized to about 10 pounds-per-square-inch. (Air pressure at sea level is 14.7 psi.) This air pressure pushes firmly against the door, sealing it to the fuselage frame. Second, the door itself is purposely designed as a wedge-shaped plug so that it can’t be blown out of its opening by accident. The higher the cabin pressure, the more tightly the door is sealed. Hence, it is patently impossible to open the door (or overwing emergency exit) of an airliner inflight!