If the oxygen system pressure is below
200 PSI, do not attempt to service
system. Make an entry on DA Form
Insure that supply cylinder shutoff valves
on the aircraft are open.
Slowly adjust the valve position so that
pressure increases at a rate not to exceed
200 PSIG per minute.
Close pressure regulating valve on
oxygen servicing unit when pressure
gage on oxygen system indicates the
pressure obtained using the Oxygen
System Servicing Pressure Chart (fig. 2-
To compensate for loss of aircraft
cylinder pressure as the oxygen cools to
ambient temperature after recharging,
the cylinder should be charged initially
to approximately 10% over prescribed
pressure. Experience will determine
what initial pressure should be used to
compensate for the subsequent pressure
loss upon cooling. A small top-off will
create little heat. A complete recharge
will create substantial heating. The
final stabilized cylinder pressure should
be adjusted for ambient temperature
per figure 2-32.
Disconnect oxygen hose from oxygen
servicing unit and filler valve.
Install protective cap on oxygen filler
Install oxygen access door.
2-102. GROUND HANDLING.
Ground handling covers all the essential information
concerning movement and handling of the aircraft while on the
ground. The following paragraphs give in detail, the
instructions and precautions necessary to accomplish ground
handling functions. Parking, covers, ground handling and
towing equipment are shown in figure 2-33.
General Ground Handling Procedure. Accidents
resulting in injury to personnel and damage to equipment can
be avoided or minimized by close observance of existing safety
standard and recognized ground handling procedures.
Carelessness or insufficient knowledge of the aircraft or
equipment being handled can be fatal. The applicable technical
manuals and pertinent directives should be studied for
familiarization with the aircraft, its components, and the
ground handling procedures applicable to it, before attempting
to accomplish ground handling.
Ground Handling Safety Practice. Aircraft equipped
with turboprop engines require additional maintenance safety
practices. The following list of safety practices should he
observed at all times to prevent possible injury to personnel
and/or damaged or destroyed aircraft:
Keep intake air ducts free of loose articles such
as rags, tools, etc.
Stay clear of' exhaust outlet areas.
During ground runup, make sure the brakes are
Keep area fore and aft of propellers clear of
Do not operate engines with control surface in
the locked position.
Do not attempt towing or taxing of the aircraft
with control surfaces until prepared to operate them.
When high winds are present, do not unlock the
control surface until prepared to operate them.
Do not operate engines while towing equipment
is attached to the aircraft, or while the aircraft is tied down.
Check the nose wheel position. Unless it is in
the centered position, avoid operating the engines at high
Hold control surfaces in the neutral position
when the engines are being operated at high power settings.
When moving the aircraft, do not push on
propeller deicing boots. Damage to the heating elements may
Change 2 2-88