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 | 11-96. General
9/8/98
AC 43.13-1B
SECTION 8. WIRING INSTALLATION INSPECTION REQUIREMENTS
11-96. GENERAL. Wires and cables
should be inspected for adequacy of support,
protection, and general condition throughout.
The desirable and undesirable features in air-
craft wiring installations are listed below and
indicate conditions that may or may not exist.
Accordingly, aircraft wiring must be visually
inspected for the following requirements:
CAUTION: For personal safety, and
to avoid the possibility of fire, turn off
all electrical power prior to starting
an inspection of the aircraft electrical
system or performing maintenance.
a. Wires and cables are supported by
suitable clamps, grommets, or other devices at
intervals of not more than 24 inches, except
when contained in troughs, ducts, or conduits.
The supporting devices should be of a suitable
size and type, with the wires and cables held
securely in place without damage to the insu-
lation.
e. Clamp retaining screws are properly
secured so that the movement of wires and ca-
bles is restricted to the span between the points
of support and not on soldered or mechanical
connections at terminal posts or connectors.
f. Wire and cables are properly supported
and bound so that there is no interference with
other wires, cables, and equipment.
g. Wires and cables are adequately sup-
ported to prevent excessive movement in areas
of high vibration.
h. Insulating tubing is secured by tying,
tie straps or with clamps.
i. Continuous lacing (spaced 6 inches
apart) is not used, except in panels and junc-
tion boxes where this practice is optional.
When lacing is installed in this manner, out-
side junction boxes should be removed and re-
placed with individual loops.
b. Metal stand-offs must be used to
maintain clearance between wires and struc-
ture. Employing tape or tubing is not accept-
able as an alternative to stand-offs for main-
taining clearance.
c. Phenolic blocks, plastic liners, or
rubber grommets are installed in holes, bulk-
heads, floors, or structural members where it is
impossible to install off-angle clamps to
maintain wiring separation. In such cases, ad-
ditional protection in the form of plastic or in-
sulating tape may be used.
d. Wires and cables in junction boxes,
panels, and bundles are properly supported and
laced to provide proper grouping and routing.
j. Do not use tapes (such as friction or
plastic tape) which will dry out in service, pro-
duce chemical reactions with wire or cable in-
sulation, or absorb moisture.
k. Insulating tubing must be kept at a
minimum and must be used to protect wire and
cable from abrasion, chafing, exposure to
fluid, and other conditions which could affect
the cable insulation. However; the use of in-
sulating tubing for support of wires and cable
in lieu of stand-offs is prohibited.
l. Do not use moisture-absorbent material
as “fill” for clamps or adapters.
m. Ensure that wires and cables are not
tied or fastened together in conduit or insulat-
ing tubing.
Par 11-96
Page 11-43