Control cables are tested to what percent of their breaking strength?

Control cables are tested to what percent of their breaking strength?

• A. 60%
• B. 80%
• C. 100%
• D. 30%

Answer: (A)

Control cables are given a static proof load that’s a defined fraction of their breaking strength to verify integrity without pushing them to failure. Breaking strength is the maximum load the cable can withstand before it will break; using a test load well below that point provides a safety margin while still revealing hidden flaws such as frayed strands, corrosion, or compromised terminations. For primary flight control cables, the standard static proof load is 60% of the cable’s breaking strength. This level is high enough to expose defects but not so high as to risk damaging a cable that could still be serviceable. If the cable passes the 60% test, it indicates the cable and its terminations can reasonably withstand the stresses expected in operation, with inspections for any signs of wear or deformation conducted afterward. Higher test levels, like 80% or 100%, aren’t the typical proof load for this purpose because they increase the risk of overlooking issues or causing unnecessary damage during testing.

Control cables are given a static proof load that’s a defined fraction of their breaking strength to verify integrity without pushing them to failure. Breaking strength is the maximum load the cable can withstand before it will break; using a test load well below that point provides a safety margin while still revealing hidden flaws such as frayed strands, corrosion, or compromised terminations.

For primary flight control cables, the standard static proof load is 60% of the cable’s breaking strength. This level is high enough to expose defects but not so high as to risk damaging a cable that could still be serviceable. If the cable passes the 60% test, it indicates the cable and its terminations can reasonably withstand the stresses expected in operation, with inspections for any signs of wear or deformation conducted afterward. Higher test levels, like 80% or 100%, aren’t the typical proof load for this purpose because they increase the risk of overlooking issues or causing unnecessary damage during testing.