When dust. contaminants, or corrosion are
detected, action is required. If the corrosion is within
repairable limits specified in the applicable MIM or
local directive. initiate corrective action. Corrective
action includes cleaning, corrosion removal,
treatment. and preservation.
The nature of some surfaces, such as chrome-,
nickel-, gold-, and silver-plated contacts. limits the use
of highly abrasive cleaning methods. You can remove
tarnish and light corrosion from these surfaces by
rubbing with one of the following materials:
An eraser (conforming to specification
ZZ-E-661) known as magic rub, ruby red, wood,
or paper encased (pencil-type) or typewriter
eraser
A nonabrasive cleaning pad (MIL-C-83957) for
laminated circuit boards. waveguides, relay
contacts. etc.
A brush (toothbrush H-T-560 or typewriter
brush H-B-681) for general scrubbing of dirt,
soil, and corrosive products on circuit
components
Remove light to heavy corrosion from surfaces,
such as covers, connectors, receptacles, antenna
mounts, equipment racks, and chassis, by hand
rubbing and by using aluminum oxide abrasive cloth.
You may use either MIL-A-9962, type I, grade A (very
fine), grade B (fine), or aluminum oxide abrasive cloth
P-C-451, 320 grit, to do this task.
USE OF COVERS AND
SHROUDS
When an aircraft is delivered by the manufacturer,
it has a complete set of tailored dust and protective
covers. Figure 4-7 shows a typical set of covers.
Install all covers so free drainage will occur. Do
NOT create a bathtub that will trap-and hold water. In
warm weather, shrouds and covers cause a greenhouse
effect, and cause condensation of moisture. Therefore,
loosen and remove shrouds and covers and ventilate
the aircraft on warm sunny days. However, where
protection from salt spray is required, leave the covers
in place, and ventilate the aircraft in good weather
Figure 4-7.—Dust and protective covers.
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