d. Oxygen masks. Oxygen masks for the pilot and copilot are provided. To connect a mask into the oxygen
system, the individual connects the line attached to the mask to the lexible hose which is attached to the cockpit
sidewall. The microphone in the oxygen mask is provided with a cord for connecting with the microphone jack. To
test mask and hose integrity, the individual places the supply control lever on the regulator control panel to the ON
position, puts on and adjusts his mask, selects TEST MASK position, and checks for leaks.
Pure oxygen will support combustion. Do not smoke while oxygen is in use. If any symptoms occur
suggestive of the onset of hypoxia, immediately set the emergency pressure control lever to the
EMERGENCY position and descend below 10,000 feet. Whenever carbon monoxide or other noxious
gas is present or suspected, set the dilutor control lever to 100% OXYGEN and continue breathing
undiluted oxygen until the danger is past.
e. Normal Operation. Oxygen pressure is maintained at all times to the regulator control panels if the cylinder
shut-off valves are open and if there is pressure in the cylinders. Each individual places the supply lever (green) on
his regulator control panel to the ON position, and the diluter lever (white) to the NORMAL OXYGEN position.
f. Emergency Operation. For emergency operation, the affected crewmember selects the EMERGENCY po-
sition of the emergency pressure control lever (red) on his regulator control panel. This selection provides 100%
oxygen at a positive pressure, regardless of the position of the diluter control lever on his panel.
g. First Aid Operation. A irst aid oxygen mask is installed in the aft cabin area as a supplemental or emergency
source of oxygen. The mask is stowed behind an overhead cover, placarded FIRST AID OXYGEN PULL. Removing
the cover allows the mask to drop out of the container, exposing a manual control valve, which releases oxygen to
the mask when placed in the ON position. After using the mask, the manual valve in the container must be turned
OFF before stowing the mask and replacing the cover.
Oxygen Duration in Minutes (140 Cubic Foot System)
TWO MAN CREW
(1) For 100% capacity of usable oxygen, 3,226 L.