Table 2-12. Recommended Fluid Dilution Chart
FLUID BY VOLUME
FREEZING POINT OF
30° and above
1. Use anti-icing and deicing fluid (MIL-A-8243) or commercial fluids.
2. Heat Mixture to a temperature of 82° to 93° C (180 to 200 F).
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 300 PSI.
When facilities for heating are not available
defrosting fluid may be used. Spray undiluted defrosting
fluid at 15 minute intervals to assure complete
undiluted defrosting fluid is expensive and slow.
If tires are frozen to ground, use undiluted
defrosting fluid to melt ice around tire. Move aircraft as
soon as tires are free.
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
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 before it is connected.
Minimum GPU requirements are as
follows: 400-amperes, 28V continuous
output DC and 11 5V, 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
stub, just outboard of the engine nacelle. An external AC
power receptacle is installed on the underside of the left
wing stub, just outboard of the engine nacelle.
SERVICING OXYGEN SYSTEM.
The oxygen system furnishes breathing oxygen to
the pilot, copilot and first aid position. Oxygen cylinder
location is shown in figure 2-22.
Oxygen System Safety Precautions.
Keep fire and heat away from oxygen
equipment. Do not smoke while
equipment, and take care not to
handled tools when working on the
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 oxygen system.