Oxygen Endurance
Hi, I have a question about the oxygen system in our Boeing 747-400.
We questioned our system, because during the required short test we noticed that the pressure dropped 10 psi. This also happened during the next consecutive tests. Therefore we decided to don the masks (all still on the ground) and use it for 2 minutes at 100% (3 pilots) In these 2 minutes we lost 110 psi from the total of the 1500psi we normally carry on board (minimum required 700psi)
So, this means that when you fly low, and when using 100% oxygen (smoke etc.) you only have less than 30 minutes oxygen......
I and my colleagues thought that we would have more endurance.
Our manuals are all blank about this subjects....
What are your views and opinions about this????