Why do airplane cabin's have to be pressurized?

Question

I watched snakes on a plane and they also said something about a gun shot blowing up the plane

Answer 1

They are strictly for people-comfort... breathing would be difficult at high altitude, and a couple of other minor things.
Also,the interior pressure is much higher than the outside pressure, so the hull of the aircraft would be compromised if penetrated, but would not "blow up" the plane.

Answer 2

Keeping the cabin pressurized makes it possible for people to breathe while at the normal cruising altitude of 37,000 feet. It would actually be fairly dangerous to fly at this altitude without a pressurized cabin or other air supply.

As for a gun shot blowing up a plane, I think that is highly unlikely. You may lose pressurization within the cabin, but I highly doubt that a bullet would cause the cabin to explode. The pressure differential between the inside and the outside is not great enough.

Answer 3

The air needs to be pressurized to maintain an artificial atmospheric pressure that mimics a lower altitude and enables oxygen density that is breathable by the average person. A plane without pressurized cabins would require oxygen masks to keep people conscious and maintain awareness and capability by warding off hypoxia(lack of breathable air) Think fighterpilots on masks or ww2 bomber crews on oxygen above 10,000 feet. In fact the average person has less than 20 seconds of consciousness without oxygen at 30,000 feets. Thye pilots keep fast donning masks at their sides in an airliner in case of depressurization to stay conscious and fly the airplane to a lower altitude with breathable air.

In a presurized aircraft a bullet hole will not cause the movie styled explosive depressurization event as air inside the sircraft rushes to diffuse itself to match the atmospheric pressure. What will happen is that you will have a leak, that is all. The pressure are not that great in this case. The snakes could have been shot, but you would run the risk of severing critical electrical or hydraulic lines or rupture a fuel tank or line causing an explosion. This is wh sky marshals arm themselves with frangable bullets that pulverize and do not over penetrate structures.

Answer 4

because the passengers would pass out from the drop in pressure on takeoff if it wasnt.

as for a gun, blowing up a plane, highly unlikely. spectacular american movie effects in my opinion. you know the 20 meters petrolium explosions when a car hits a pole....