Spent 6 months torqueing to the upper limit, then an old A&P at Tulsa showed me his trick

Wren Stone · 2026-09-18T20:30:03.338642+00:00

I always torqued fasteners to the high end of the range because I figured tighter had to be safer. Last summer I was doing a landing gear inspection on a Cessna 182 and an A&P with 34 years in the trade pointed out something I had never noticed, every single one of my torque seals was cracked or flattened. He told me "the middle of the range is where the engineers actually did their math" and that the low end exists for a reason. I started setting my wrench to the middle value on everything from spark plugs to brake caliper bolts and checked back after about 200 hours of flight time. Zero leaks, zero backing off, and the seals looked brand new when I pulled them. I used to think staying in the range was all that mattered, but where you land in that range clearly changes how the joint wears. Now I keep a little chart in my box with the mid values for the common fasteners I see. What range do you guys aim for on stuff like oil pan bolts where the spread is pretty wide?

HW Forums

Loading…

Spent 6 months torqueing to the upper limit, then an old A&P at Tulsa showed me his trick | Aircraft Mechanics - HW Forums