The reason for not being able to open the airplane door in mid-air

The opening of the emergency exit when the plane is at 11,000m is impossible, requiring force equal to the weight of two African elephants.

If you use your hand to not open the emergency door when the plane is flying at the cruise altitude (11,000 m), a man needs to work more than 10,750kg , equivalent to lifting nearly two African elephants or six hippos adult males, according to Live Science.

A man named Joseph Daniel Hudek from Tampa, Florida, USA, tried to open the emergency door about an hour after Delta Airlines Boeing 767 departed from Seattle to Beijing on July 6. The pilot was forced to turn the plane around and land on the Seattle-Tacoma International Airport. But experts point out that Joseph is not strong enough to open the door if he only uses his hand from a physical perspective.

The pressure difference made it difficult to open the plane in mid-air.(Photo: Wordpress).

The pressure inside the conventional aircraft cabin is never lower than the pressure at an altitude of 2,400m above sea level, according to John-Paul Clarke, aviation engineering professor and director of the Air Transport Laboratory. Georgia Institute of Technology. " The bottom line is that at altitudes exceeding 2,400m, the internal pressure is greater than the external pressure , " Clarke said.

Furthermore, the aircraft door was made so that the face turned outwards to be smaller than the face facing into the cabin. This design makes a person unable to push the closed door open from the inside. " In fact, you have to pull the door in, rotate the door before pushing the door out , " Clarke said.

Due to the door design, a person will have to overcome the pressure difference to pull in the door if the plane is surfing at an altitude of over 2,400m."At the height of the journey, the pressure difference is extremely large," Clarke stressed.

According to Clarke's estimate, the pressure at an altitude of 2,400m is 75,260 pascal (Pa) and the pressure at the height of the journey (11,000m) is 23,000 Pa. The exit door of the Boeing 767 is 1.88 x 1.07 meters. In order to calculate the force needed to pull in the door at the height of the journey, we calculate the pressure difference and multiply it by the door area. The result is a 10,750kg horizontal force.

However, the story will change if the plane is below 2,400m . "Under 2.400m, the pressure is controlled to correspond to the external pressure, which is why your ear hurts only when the plane drops from 2,400. The pressure difference between inside and outside the aircraft is very small. or not so the door opening is much easier , "Clarke said.