Shoutout to the old guy who told me wire shielding gets worse over time

Was digging through a 1993 service bulletin last week and it said that 30-year-old shielding can lose up to 40% of its effectiveness just from vibration alone. Has anyone else noticed more noise in older planes that you couldn't explain by just bad connections?

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sean_walker454mo ago

Read some article about how aircraft shielding braid actually work-hardens from vibration over time, making it more brittle and less effective at conducting RF. Really explains why those old coax runs start acting up even with clean connections.

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perry.karen4mo ago

Honestly this is one of those things that sneaks up on you. I've swapped out a harness on a 1978 Piper that looked totally fine on the outside but the inner shielding was basically dust when you touched it. The vibration just slowly grinds the braid down against itself over decades. If you've got an older plane and you're chasing weird static that changes with engine RPM, don't just clean the connectors first. Grab a multimeter and check the shield continuity between both ends of each wire. Tbh I found a broken shield on a radio coax once that looked perfect until I wiggled it at the crimp. The fix is usually just replacing that single wire run instead of the whole bundle.

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