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Serious question, an old A&P told me to torque by feel not by spec, and I've been arguing about it since
Back in 2016 a lead mechanic named Dale at a shop in Bakersfield told me the torque wrench was for the logbook, not the nut, and that after 20 years your wrist knows better. I laughed it off, but last spring on a Cherokee flap actuator I went by feel on two bolts and one was so loose the inspector caught it in 30 seconds. Dale's side says specs are written for lawyers and engineers, and real feel accounts for thread wear and lube that a dry table number never will. My side says a calibrated wrench costs less than a prop strike and your wrist has no traceable paperwork. So which is it, do you trust the book or the hand that's been doing this since before I was born?
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lunar898h ago
The thing nobody ever brings up in this fight is that torque specs assume clean, dry threads unless the manual says otherwise, and half the bolts on a 40 year old plane have been oiled, anti-seized, or stretched by some guy before you. A lubed bolt torqued to the dry number can be 25 percent overstretched, so Dale IS right that the book number isn't always the real number. But the answer isn't your wrist, it's looking up the wet torque value or measuring bolt stretch on the critical stuff. Feel can't tell you if a bolt is already past its elastic limit, and that's the part that kills people. A wrench with a known setting and threads prepped right beats both the book and the hand every single time. Trust the spec, but only after you check what the spec was written for.
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