a. Deterioration Factors. Deterioration problems
result from sand and dust, high day temperatures,
terrain. Considerations for each problem are explained
in the following paragraphs.
(1) Sand and dust. The large quantities of
loose sand and dust create serious erosion problems for
rotor blades, propellers, turbine engine compressors,
windshields and other exposed surfaces of the aircraft
While sitting on the ground, the aircraft is exposed to
blowing sand and dust from frequent desert windstorms
and sand and dust clouds created by vehicular traffic
and operation of other aircraft nearby. Sand and dust
particles collect on all surfaces of the aircraft and will
penetrate almost any crack or crevice to accumulate
Inside the aircraft. Electronic gear and optical
equipment are very susceptible to sand and dust.
Weapons are particularly susceptible since many parts
are often covered with a light coat of lubricant.
(2) High day temperature. In the desert,
equipment. The temperature inside a parked aircraft
which has been closed up to keep the sand and dust out
can reach temperatures much higher than outside
temperatures Extreme heat can cause the failsafe
device in electronic gear to shut the equipment off.
High temperatures can cause lubricants to break down,
distort seals and gaskets, and result in Increased leaking
problems. Other problems due to high temperatures
include softening of plastics, high stress on pressurized
containers, and shortened battery life.
temperatures can reach over 100 °F (38°C), while night
time temperatures could reach freezing (or close to it)
temperature variation contributes to increased corrosion.
(4) Ultraviolet radiation. The abundant
desert sunlight produces a high level of ultraviolet
components to become very brittle and easily cracked
Ultraviolet radiation also accelerates deterioration of
nylon webbing used in seats and restraint systems.
(5) Terrain. The terrain causes problems
with moving aircraft and associated support equipment
on the ground Sand can bog a vehicle or aircraft down
to the axles. A condition known as Cap Rock Is often
encountered The terrain appears rocky, however, the
substrate will not support weight and a vehicle can sink
up to the frame when attempting to travel over Cap
Rock. Aircraft tires can easily be damaged In rocky
b. Precautions. Maintenance personnel will
observe the following precautions as a guide to
successful performance of duty under desert conditions:
Severe burns can result when bare
skin touches metal parts of aircraft
· Exercise caution when touching aircraft surfaces or
metal tools that have been exposed to the sun.
Wear gloves and use mats or pad, when practical, to
prevent burns or blisters.
· Use extreme care when handling engine fuel at
temperatures above 120°F (
49oC), to prevent
possible sparks and explosion. Open gasoline
drums with bronze or other nonsparking tools.
· Electronic gear and optics must be shielded from
direct sunlight and/or otherwise cooled for efficient
c. Inspection and Maintenance. The following
procedures are for the inspection and maintenance of
aircraft operating in desert conditions:
Frequent use of a vacuum cleaner will
prevent accumulation of sand and dust
in aircraft. Pay particular attention to
(1) Inspect bungee cords, seals, tires, etc.,
frequently for blisters and other signs of deterioration.
(2) Inspect vibration Isolators every two
weeks and replace where cracking or permanent set is
(3) Keep a chart showing engine oil
consumption. A sharp rise on the chart will indicate
faulty or inefficient engine operation. An inefficient
engine should not be continually operated. It is better to
correct the trouble so the engine will operate at peak
(4) Inspect, clean, or replace filters at
regular intervals. Sand and dust quickly choke fuel and
oil filters and air cleaners. Keep an adequate reserve
stock of cleaners and filters.