Technical data

13773-001
20-90
Page 1
CABLE INSPECTION
1. DESCRIPTION
This section covers procedures necessary for the proper inspection of control cables.
2. MAINTENANCE PRACTICES
A. Control Cables (See Figure 20-901)
Control cable assemblies are subject to a variety of environmental conditions and forms of deteriora-
tion that ultimately may be easy to recognize such as wire/strand breakage. The not so readily visible
types of deterioration include corrosion and/or distortion. The following information will aid in detecting
these cable conditions. Carefully examine any cable for corrosion that has a broken wire in a section
not in contact with wear-producing airframe components such as pulleys, fairleads, rub blocks, etc. It
may be necessary to remove and bend cable to properly inspect it for internal strand corrosion as this
condition is usually not evident on outer surface of cable. Replace any cable that has internal corro-
sion. If a cable has been wiped clean of its corrosion-preventive lubricant and metal-brightened, the
cable shall be examined closely for corrosion.
(1) Inspecting
(a) Examine cables for broken wires by passing a cloth along the entire length of the cable.
Broken wires will be detected if the cloth snags on cable. Critical areas for wire breakage
are those sections of cable which pass through fairleads, across rub blocks, and around
pulleys. If no snags are found, then no further inspection is required. If snags are found or
broken wires are suspected, then a more detailed inspection is necessary which requires
that the cable be bent in a loop to confirm broken wires. Loosen or remove cable to allow
it to be bent in a loop as shown. While rotating cable, inspect bent area for broken wires.
(b) Individual broken wires are acceptable in primary and secondary control cables at random
locations. No more than six broken wires in any given ten-inch cable length is allowable.
30 Nov 2000