TM 55-1510-215-10
(a) The emergency pressure control
lever has three positions, two positions control oxygen
WARNING
consumption for the individual using oxygen, and the
remaining position serves for testing hose and mask
integrity. In the EMERGENCY position, the control lever
If any symptoms occur suggestive of
causes 100% oxygen to be delivered at a safe, positive
the onset of hypoxia, immediately set
pressure. In NORMAL position, the lever allows delivery
the emergency pressure control lever
of normal or 100% oxygen depending upon the selection
to the EMERGENCY position and
of the diluter control lever. In TEST MASK position
descend
below
10,000
feet.
100% oxygen at positive pressure is delivered to check
Whenever carbon monoxide or other
hose and mask integrity.
noxious gas is present or suspected,
set the diluter control lever to 100%
(b) The 2000 PSI oxygen pressure
OXYGEN and continue breathing
gage provided on the oxygen control panels should at no
undiluted oxygen until the danger is
time indicate over 400 PSI. If the pressure exceeds 400
past.
PSI, a malfunction of the pressure reducer is indicated.
Whenever oxygen is inhaled, a blinker-vane slides into
view within the flow indicator window, showing that
(2) Oxygen masks. Oxygen masks for the
oxygen is being released. When oxygen is exhaled, the
pilot and copilot are provided as personal equipment. To
blinker-vane vanishes from view.
connect a mask into the oxygen system, the individual
connects the line attached to the mask to the flexible
NOTE
hose which is attached to the cockpit sidewall. The
microphone in the oxygen mask is provided with a cord
Check to insure that the OXYGEN
for connecting with the helmet microphone jack. To test
SUPPLY PRESSURE gage registers
mask and hose integrity, the CREW OXYGEN shut-off
adequate pressure before each flight.
valve is turned on, then the individual places the supply
A check of the supply pressure
control lever on the regulator control panel to the ON
should be made at intervals during
position, dons and adjusts his mask, selects TEST
flight to note the quantity available
MASK position, and checks for leaks.
and to approximate the supply
duration. The outside temperature is
NOTE
reduced as an aircraft ascends to
higher altitudes. Oxygen cylinders
A loss of oxygen will occur if the
thus cooled by temperature change
CABIN OXYGEN valve is OPEN, and a
will show a pressure drop. This type
passenger
oxygen
mask
is
of drop in pressure will raise again
connected to any of the outlets.
upon return to a lower or warmer
altitude.
A valid cause for alarm
b. Normal Operation. For normal operation of the
would be the rapid loss of oxygen
oxygen system, the pilot rotates the cockpit or cabin
pressure when the aircraft is in level
oxygen shut-off valve (fig. 2-17) to OPEN, then each
flight or descending; should this
individual places the supply lever (green) on his
condition arise, descend as rapidly
regulator control panel to the ON position, the diluter
as possible to an altitude which does
lever (white) to the NORMAL OXYGEN position, and the
not require the use of oxygen.
emergency pressure lever (red) to the NORMAL
position. To obtain oxygen for the passengers, the pilot
rotates the CABIN OXYGEN valve to OPEN causing
WARNING
100% oxygen to flow continuously into the distribution
lines which supply passenger masks coupled into the
Pure
oxygen
will
support
service outlets.
combustion. Do not smoke while
NOTE
oxygen is in use.
The shutoff valves of high pressure
oxygen systems should be opened
fully to prevent the possibility of
leakage.
2-53
