01 March 2005
15 July 2008
6-2.13. MOISTURE TRAPS AND CAVITY AREAS.
Inspect for moisture traps and cavity areas at rear of
equipment shelves. Treat in accordance with paragraph
For additional information on bonding and
the applicable service directives.
6-2.15. ELECTRICAL BONDING AND GROUNDING
STRAPS. The bonding and grounding straps used on
aircraft and avionic equipment are a major source of
galvanic corrosion. In most cases, the bonding or
grounding strap is made of a metal that is dissimilar to
the mating surface. This creates a galvanic couple that
a. If necessary, before painting fill depression areas
in the presence of moisture will corrode rapidly. Treat
and cavities with Sealing Compound, MIL-PRF-81733
6-3. REPAIR OF AVIONIC SYSTEMS, EQUIPMENT,
b. Apply sealing compound and finish in accordance
with Volume II (Navy and Army) or TO 1-1-691/TO
1-1-8 (Air Force).
6-3.1. ANTENNA SYSTEMS. Antenna systems are
normally exposed to fairly severe environments.
6-2.14. COCKPIT INDICATOR AND MOUNTING
Without adequate corrosion protection, these systems
HARDWARE. Inspect cockpit indicator and mounting
can fail via shorts, open circuits, loss of dielectric
hardware for dirt, dust, and corrosion. Treat as follows:
a. Remove corrosion and clean in accordance with
to the aircraft can also result. Antennas mounted on
the fuselage require openings in the skin to route the
various lines to the antenna. The area around the
b. Clean indicator faces in accordance with
antenna mounting is susceptible to moisture intrusion
fluids (e.g., fuel, engine oil, or hydraulic fluid) Antennas
c. Where required, replace decal in accordance
mounted on the lower fuselage are particularly corrosion
with the applicable service directives.
prone. The inspection and treatment process are
outlined in the following paragraphs.
Compound, Corrosion Preventive
Instructions on recognizing corrosion are
outlined in Volume I. If corrosion is beyond the
surface stage (i.e. pitting and cracking), refer
Compound, Corrosion Preventive 26
to Volume II (Navy and Army) or TO 1-1-691
( A i r Force) for assessment/treatment
d. Apply Water Displacing Corrosion Preventive
Compound, MIL-C-81309 Type II (Volume IV or V,
6-3.1.1. Corrosion Visual Inspection. A visual check
of the antenna mounting base metal surface can
MIL-DTL-85054, Clear (Amlguard) (Volume IV or V,
reveal signs of corrosion attack. Corrosion deposits
are the most obvious indication that an attack has
taken place. Since antennas are usually mounted on
e. Touch up all bare metal in the cockpit area with
aluminum structural materials, corrosion (deposits of
the appropriate coating system.
aluminum oxide) generally can be identified as a white
or greyish-white powder.