FAA Aviation Mechanic General (AMG)Materials, Hardware and ProcessesMedium
A mechanic is fabricating a new control cable terminal for a flight control system using swaging. Assuming the cable has a nominal diameter of 1/8 inch, what is the maximum permissible number of broken wires in any 1-inch length for a 7x19 extra-flexible cable before it must be replaced?
- A3 broken wires
- B1 broken wire
- C9 broken wires
- D6 broken wires
Show answer & explanationAnswer & explanation
Correct answer: D. 6 broken wires
For 7x19 extra-flexible cables, the maximum allowable number of broken wires in any 1-inch length is 6. This applies regardless of the cable diameter, as long as it's a 7x19 type.
Why the other options are wrong
- A. 3 broken wires is the limit for 7x7 flexible cable, not 7x19 extra-flexible.
- B. 1 broken wire is incorrect for 7x19 cable; it's too stringent.
- C. 9 broken wires exceeds the allowable limit for 7x19 cable.
Aircraft Cable Inspection Limits
Specific limits on the number of broken wires allowed in a certain length of aircraft control cable before replacement is mandatory, varying by cable construction type.
- 7x7 flexible cable: 3 broken wires allowed in any 1-inch length.
- 7x19 extra-flexible cable: 6 broken wires allowed in any 1-inch length.
- Broken wires near a terminal fitting are more critical.
Memory trick: Cable's broken strands, a critical number demands.