with defrosting fluid. Spraying defrosting fluid on aircraft
surfaces before installing protective covers will permit
protective covers to be removed with a minimum of
sticking. To prevent freezing rain and snow from blowing
under protective covers and diluting the fluid, ensure that
protective covers are fitted tightly. As a deicing measure,
keep exposed aircraft surface wet with fluid for protection
Use undiluted anti-icing, deicing, and defrosting fluid
(MILA-8243) to treat aircraft surfaces for protection
against freezing rain and frost Spray aircraft surface
sufficiently to wet area, but without excessive drainage. A
fine spray is recommended to prevent waste. Use diluted,
hot fluid to remove ice accumulations.
Remove frost or ice accumulations from aircraft
surfaces by spraying with diluted anti-icing, deicing, and
defrosting fluid mixed in accordance with Table 2-12.
Spray diluted, hot fluid in a solid stream (not over
15 gallons per minute). Thoroughly saturate aircraft
surface and remove loose ice. Keep a sufficient quantity
of diluted, hot fluid on aircraft surface coated with ice, to
prevent liquid layer from freezing. Diluted, hot fluid
should be sprayed at a high pressure, but not exceeding
c. When facilities for heating are not available and it
is deemed necessary to remove ice accumulations from
aircraft surfaces, undiluted defrosting fluid may be used.
Spray undiluted defrosting fluid at 15 minute intervals to
assure complete coverage Removal of ice accumulations
using undiluted defrosting fluid is expensive and slow.
d. If tires are frozen to ground, use undiluted
defrosting fluid to melt ice around tire. Move aircraft as
soon as tires are free.
2-101. APPLICATION OF EXTERNAL POWER.
Before connecting the power cables from the
external power source to the aircraft, ensure that
the GPU is not touching the aircraft at any point
Due to the voltage drop in the cables, the two
ground systems will be of different potentials.
Should they come in contact while the GPU is
operating, arcing could occur. Turn off all
external power while connecting the power cable
to, or removing it from, the external power supply
receptacle. Be certain that polarity of the external
power source is the same as that of the aircraft
requirements are as follows: 400-amperes, 28V
continuous output DC and 115V, 3 phase, 400
cycle, 3 KVA continuous output AC.
An external power source is often needed to supply.
The electric current required to properly ground service
the aircraft electrical equipment and to facilitate starting
the aircraft's engines. An external DC power receptacle is
installed on the underside of the right wing, just outboard
of the engine nacelle. An external AC power receptacle is
installed on the underside of the left wing, just outboard of
the engine nacelle.
2-102. SERVICING OXYGEN SYSTEM.
The oxygen system furnishes breathing oxygen to
the pilot, copilot, and first aid position. The oxygen
cylinder location is shown in figure 2-24.
Oxygen System Safety Precautions.
Keep fire and heat away from oxygen equipment
Do not smoke while working with or near oxygen
equipment, and take care not to generate sparks
with carelessly handled tools when working on
the oxygen system.
(1) Keep oxygen regulators, cylinders, gages,
valves, fittings, masks, and all other components of the
oxygen system free of oil, grease, gasoline, and all other
readily combustible substances. The utmost care shall be
exercised in servicing, handling, and inspecting the
(2) Do not allow foreign matter to enter oxygen
(3) Never allow electrical equipment to come into
contact with the oxygen cylinder.
(4) Never use oxygen from a cylinder without first
reducing its pressure through a regulator.
Replenishing Oxygen System.
Remove oxygen access door on outside of
aircraft (fig. 2-24).
Remove protective cap on oxygen system
Attach oxygen hose from oxygen servicing
unit to filler valve.
If the oxygen system pressure is below 200 PSI,
do not attempt to service system Make an entry
on DA Form 240813