STUDENT GUIDE T-39N/G NATOPS
11. The following warnings occur at 13,500 + 500:
a. DON OXYGEN MASK light on.
b. NO SMOKING light on.
c. Oxygen warning horn on.
C. Oxygen system
1. Two 77.9 cubic-foot oxygen cylinders located in cabin. (Aircraft specific)
a. Check ON during preflight (normally safety wired ON).
b. Normal servicing 1500-1800 psi.
c. Green blowout disk aft of entry door if pressure exceeds 2500-2700 psi.
d. All occupants shall use oxygen above FL 410.
e. Pilot/Copilot have oxygen available at all times provided the oxygen cylinders are
ON and masks are plugged in (no electrical power needed). For other stations,
switch on oxygen control panel must be in MAN or AUTO.
2. Oxygen regulators
a. Masks at each station.
b. Diluter-demand regulators
d. Flow indicators (green/orange band). Green = Oxygen available.
* In the event oxygen masks are donned:
(1) Deselect VOX mic (use intercom button/toggle to talk).
(2) Select OXY mask vice BOOM (for mic).
(3) Front seats select Speaker (back seats do not have this available, speakers in
cabin are for intercom P.A. system)
3. Passenger Oxygen control panel (pilot's LH console)
a. Oxygen pressure gauge (1500-1800 psi).
b. Oxygen warning horn cutout button.
c. PASSENGER OXYGEN ON red light (press to test) will be on whenever oxygen is
available in cabin.
d. OFF -no flow
MANUAL - continuous flow
AUTO - normal position allowing flow if cabin altitude exceeds 13,500 + 500 MSL.
4. Walkaround bottle located behind co-pilot seat.