01 March 2005
Change 1
NAVAIR 01-1A-509-3
15 July 2008
TM 1-1500-344-23-3
TO 1-1-689-3
6-2.13. MOISTURE TRAPS AND CAVITY AREAS.
NOTE
Inspect for moisture traps and cavity areas at rear of
equipment shelves. Treat in accordance with paragraph
For additional information on bonding and
grounding straps, refer to paragraph 6-4 and
the applicable service directives.
6-2.15. ELECTRICAL BONDING AND GROUNDING
STRAPS. The bonding and grounding straps used on
Sealing Compound
2
aircraft and avionic equipment are a major source of
Corrosion Inhibitive
galvanic corrosion. In most cases, the bonding or
MIL-PRF-81733
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
in accordance with paragraphs 6-5 through 6-5.3.
(Volume IV or V, Chapter 2).
6-3. REPAIR OF AVIONIC SYSTEMS, EQUIPMENT,
b. Apply sealing compound and finish in accordance
AND COMPONENTS.
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:
strength, signal attenuation, poor bonding, or
electromagnetic interference (EMI). Structural damage
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
paragraph 6-2.7.f. Polish glass with clean flannel cloth.
from rain, condensation, aircraft washing, and internal
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.
NOTE
Compound, Corrosion Preventive
3
Water-Displacing
Instructions on recognizing corrosion are
MIL-C-81309
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
MIL-DTL-85054
( A i r Force) for assessment/treatment
techniques.
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
Chapter 2) or Corrosion Preventive Compound,
of the antenna mounting base metal surface can
MIL-DTL-85054, Clear (Amlguard) (Volume IV or V,
reveal signs of corrosion attack. Corrosion deposits
Chapter 2), on mounting hardware.
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.
