One Tuesday in August, every torque wrench in the hangar lied to me

We had a Piper Cherokee in for annual, and I was doing the landing gear retraction test. I torqued the bolts to spec, 65 ft-lbs, marked them, moved on. Later that afternoon the owner calls, says he heard a pop on the way home. Brought it back, and the bolt was loose. I grab my torque wrench, test it against the calibration checker, and it clicks at 52. All six wrenches in the tool room were off by anywhere from 8 to 15 ft-lbs. Nobody had sent them out in over a year. The shop foreman went pale. We spent the next three days re-torquing every control surface bolt on every plane in the hangar, about 12 aircraft total. That was a slow, painful week, but honestly, I'm glad we caught it before a flight control let go. Anyone else ever found a whole batch of tools drifting at once? How did your shop handle the rework?

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wadeyoung1mo ago

The part about all six wrenches being off at once is what gets me. That's not a coincidence, that's a whole program failing quietly. In my shop we had something similar happen years ago, turns out the calibration guy retired and nobody picked up his job. We ended up buying a good digital torque tester and now every wrench gets checked first thing Monday morning, takes ten minutes. For the rework, we did exactly what you did, went through everything with a fresh set of wrenches and a logbook. The painful part is trusting your own work after that, you second guess every click. But it sounds like your foreman did the right thing, better three days of hell than a lawsuit or worse.