NAVAIR 01-1A-509-3
01 March 2005
TM 1-1500-344-23-3
TO 1-1-689-3
TREATMENT OF SPECIFIC AREAS
6-1. GENERAL. All aircraft electrical/electronic units
NOTE
must be opened and inspected for evidence of internal
moisture and corrosion. When corrosion is detected,
The use of dissimilar metals in the selection of
prompt corrective action is required. This action shall
s c r e w s , washers, and nuts should be
consist of cleaning, corrosion removal, treatment, and
eliminated wherever possible. Refer to
preservation, where required. Maintenance personnel
should always use the mildest method available to
grounding hardware.
remove corrosion. The procedures and techniques of
corrosion removal outlined in the following paragraphs
a. Clean and inspect hardware, fixed mountings,
are intended to assist avionic technicians in equipment
and points of metal bonds for signs of galvanic
repair. In each case, some discretion on the part of
corrosion. Pay particular attention to areas of dissimilar
maintenance personnel is warranted. It is important
metal.
that personnel analyze the problem, select the
appropriate corrective action, and confirm corrosion
b. R e m o v e corrosion with Abrasive Cloth,
control effectiveness. It is recommended that Volume
ANSI-B 74.18 320 Grit Type I Class I (Volume IV or V,
I be reviewed for basic information on what avionic
corrosion is, why it occurs, and the various forms it can
take.
6-2. REPAIR OF AVIONIC EQUIPMENT HOUSING,
MOUNTING, AND STORAGE HARDWARE.
Compound, Aircraft Cleaning
4
MIL-PRF-85570
6-2.1. BILGE AREAS. A common trouble spot on all
aircraft is the bilge area, especially in helicopters.
c. Clean affected areas with a solution of nine parts
These areas contain all types of avionic equipment
fresh water to one part Aircraft Cleaning Compound
and present a natural sump or collection point.
Accumulation of waste, hydraulic fluids, water, dirt,
Apply with Cleaning Cloth CCC-C-46 Class 7
loose fasteners, drill shavings and other debris is
typical. Liquids shall be pumped or drained from bilge
areas. Bilge areas should be cleaned before equipment
d. Rinse with fresh water and wipe dry with Cleaning
replacement. All efforts should be made to ensure that
avionic equipment is cleaned and preserved before
being returned to these areas. Bilge areas shall be
cleaned and preserved in accordance with Volume II
(Navy and Army) or TO 1-1-691 (Air Force).
Coating, Chemical Conversion
10
MIL-DTL-81706
6-2.2. EQUIPMENT BAYS. Avionic equipment bays
and installed equipment are highly susceptible to
CAUTION
corrosion. This is especially true in helicopters and
aircraft using external ram air cooling. The avionics
E x e r c i s e care when using Chemical
technician should routinely survey the inside of
Conversion Material, MIL-DTL-81706, near
equipment bays whenever he/she is working in these
electronic hardware. It can cause corrosion of
areas, and report evidence of any corrosion. The
the delicate electronic devices if they are not
inspection and treatment processes are outlined in the
suitably protected.
following paragraphs.
e. After corrosion is removed, aluminum surfaces
shall be treated with Chemical Conversion Material,