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Found a cracked bellcrank on a Cessna 172 during annual last week
The bolt was torqued fine but the forging had a hairline split right at the bend. Anyone else run into hidden stress fractures on older airframes that looked fine until the dye check?
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wendy6287d ago
We found two cracked exhaust risers on a 1978 172 last month. Dye check caught them but visually they looked totally fine. The metal had this tiny hairline right where the pipe bends. It's scary because you can torque things to spec and still miss a fatigue crack. I'd dye check every high stress area on anything built before 1980. These older airframes are getting tired even if the logbooks look clean.
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michael_jenkins396d ago
Had a guy at the shop tell me he found cracks on a 70s Cherokee that looked fine until he hit it with dye. @wendy628 is right, those hairline cracks hide in plain sight on older metal.
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