[Rebelbase]

Question, is there 17 hours of oxygen contained within the pressurized fuselage tube holding 200 passengers?

If not is there supplemental oxygen added during flight?

[Axenolith]

Its just air compressed from outside.

[Cronos]

Air is continuously “bled” from the engines. The Engines compress the air and it is put into the cabin and eliminated out from the back. The entire air is replaced every 10 to 15 minutes in continuous circulation.