Flight Detent
7th Mar 2006, 10:25
I've been discussing the content of the B737NG FCOM VOL II in the area if pilot oxygen masks and their operation.
In section 1.40 there is a section which tells me that the oxy masks automatically go to 'pressure breathing' above 27,000 feet cabin altitude.
I don't think this is correct with the current type of mask. Our masks are the type that are one piece, with the clear visor and the regulator built into the front of the mouth piece, Norm, 100% and Emerg.
This 27,000 feet thing applied to the older type masks that had the regulator with the three selector levers on the front, mounted in the panel, and the mask itself was just a mouthpiece and visor.
These current ones only adjust the Norm dilution of air/oxy according to the cabin altitude, and thats all, as I understand it!
You don't get 'pressure breathing' at any time unless you select Emerg position on the mask selector (damn difficult thing!!)
Any comments about this VOL II wording being misleading!
Cheers, FD :uhoh:
In section 1.40 there is a section which tells me that the oxy masks automatically go to 'pressure breathing' above 27,000 feet cabin altitude.
I don't think this is correct with the current type of mask. Our masks are the type that are one piece, with the clear visor and the regulator built into the front of the mouth piece, Norm, 100% and Emerg.
This 27,000 feet thing applied to the older type masks that had the regulator with the three selector levers on the front, mounted in the panel, and the mask itself was just a mouthpiece and visor.
These current ones only adjust the Norm dilution of air/oxy according to the cabin altitude, and thats all, as I understand it!
You don't get 'pressure breathing' at any time unless you select Emerg position on the mask selector (damn difficult thing!!)
Any comments about this VOL II wording being misleading!
Cheers, FD :uhoh: