How is there a constant supply of oxygen in a plane? Dosn't it run out?

Answer 1

Are you talking about the emergency supply of oxygen that will flow through the oxygen masks in case of an emergency? Or are you talking about your normal breathing air?

To understand this, let's talk a little bit of (simplified) theory first. A cubic meter of air at sea level occupies the exact same space as a cubic meter of air at 35,000 feet. But because of a decrease of pressure with an increase in altitude, the cubic meter of air at 35,000 feet will contain a lot less oxygen molecules. Too few for your lungs to utilize, so if you tried to breathe the air at that altitude you would pass out in under one minute. To make it possible to breathe up there, the cabin is pressurized, air is taken from the intake compressor in the jet (Before the air has gotten to the 'dirty' parts of the engine), cooled (Because of the compression the air is actually very hot at this point), then introduced in to the cabin. Depending on the model of airplane, the inside of the cabin will have the same air pressure as one would have at between 6,000 to 8,000 feet of altitude, with plenty of oxygem molecules per unit of air, more than enough for us to breathe. So, because there is an unlimited supply of air from the outside of the airplane, normal air does not run out.

However, there is emergency oxygen onboard. This in case the pressurization fails. It's the familiar 'dropping masks'. This oxygen supply is very limited, and will normally only carry enough oxygen with it to provide the passengers with oxygen for a couple of minutes, enough time for the airplane to decend from cruise altitude to an altitude where the unpressurized air is breathable.

Answer 2

A commercial jet is pressurised to a pressure equal to 10000 ft ie. minimum breathable pressure. If there was a sudden loss of air pressure, oxygen masks would be deployed and would only be neccessary until the plane decended to 10000ft from the normal altitude of about 35000 ft..........Are you talking about the oxygen masks or the normal air in the cabin. Air at 35000ft is so thin that it would not sustain life, therefore it is pumped into the aircraft from outside.

Answer 3

Why would it run out, there is oxygen up there. The air is pressurised for the cabin to about 8000 feet so the pressure is less than sea level but its OK to breath. when the aircraft descends to 8000ft the pressure in and out becomes equal.
Hope that makes sense.

Answer 4

Air is taken from the engines.
Then it is compressed to compensate for the thin air.
Then pumped into the cabin.
Also some of the air is also recycled.

Answer 5

They recycle some and take stuff from outside into filters and pump it round the plane

Answer 6

Music [2]

Answer 7

there is fresh air constanly pumped in from outside

Answer 8

Its bottled. And automatic Climate controlled.

Answer 9

The air is recycled.