FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 11. Aircraft Electrical Systems | 8. Wiring Installation Inspection Requirements | 11-98. Terminals and Terminal Blocks
AC 43.13-1B CHG 1
9/27/01
e. Check wiring that shows evidence of
overheating (even if only to a minor degree)
for the cause of the overheating.
f. Wiring on which the insulation has be-
come saturated with engine oil, hydraulic fluid,
or another lubricant.
g. Wiring that bears evidence of having
been crushed or severely kinked.
h. Shielded wiring on which the metallic
shield is frayed and/or corroded. Cleaning
agents or preservatives should not be used to
minimize the effects of corrosion or deteriora-
tion of wire shields.
i. Wiring showing evidence of breaks,
cracks, dirt, or moisture in the plastic sleeves
placed over wire splices or terminal lugs.
j. Sections of wire in which splices occur
at less than 10-foot intervals, unless specifi-
cally authorized, due to parallel connections,
locations, or inaccessibility.
k. When replacing wiring or coaxial ca-
bles, identify them properly at both equipment
and power source ends.
l. Wire substitution-In the repair and
modification of existing aircraft, when a re-
placement wire is required, the maintenance
manual for that aircraft should first be re-
viewed to determine if the original aircraft
manufacturer (OAM) has approved any sub-
stitution. If not, then the OAM should be
contacted for an acceptable replacement.
m. Testing of the electrical and chemi-
cal integrity of the insulation of sample wires
taken from areas of the aircraft that have expe-
rienced wiring problems in the past, can be
used to supplement visual examination of the
wire. The test for chemical integrity should be
specific for the degradation mode of the insu-
lation. If the samples fail either the electrical
or chemical integrity tests, then the wiring in
the area surrounding the sampling area is a
candidate for replacement.
11-98. TERMINALS AND TERMINAL
BLOCKS. Inspect to ensure that the follow-
ing installation requirements are met:
a. Insulating tubing is placed over termi-
nals (except pre-insulated types) to provide
electrical protection and mechanical support
and is secured to prevent slippage of the tubing
from the terminal.
b. Terminal module blocks are securely
mounted and provided with adequate electrical
clearances or insulation strips between
mounting hardware and conductive parts, ex-
cept when the terminal block is used for
grounding purposes.
c. Terminal connections to terminal
module block studs and nuts on unused studs
are tight.
d. Evidence of overheating and corro-
sion is not present on connections to terminal
module block studs.
e. Physical damage to studs, stud threads,
and terminal module blocks is not evident.
Replace cracked terminal strips and those
studs with stripped threads.
f. The number of terminal connections
to a terminal block stud does not exceed four,
unless specifically authorized.
g. Shielding should be dead-ended with
suitable insulated terminals.
h. All wires, terminal blocks, and indi-
vidual studs are clearly identified to corre-
spond to aircraft wiring manuals.
Page 11-46
Par 11-97