That time I ignored the torque wrench specs on a landing gear bolt at JFK

I was working night shift on a 737 at JFK a couple years ago, and the manual said 52 ft-lbs for this main gear drag brace bolt. But my torque wrench was acting up and I figured I knew the feel after 12 years. So I just snugged it up with a ratchet, maybe a bit more. Next morning, the plane went out and I got a call from the night foreman around 2 AM. Said the bolt sheared off during a hard landing and the drag brace was hanging loose. They had to swap the whole gear assembly, cost the company like $12,000 in parts and OT. I felt like an idiot. Now I check my torque wrench calibration every shift, even if it's a pain. Has anyone else here learned a hard lesson about skipping the torque specs?

2 comments

2 Comments

susanm561mo ago

You said "the bolt sheared off during a hard landing" and that's the part I'd want to push back on a little. I'm not saying you didn't mess up skipping the torque wrench, but a hard landing is a hard landing. Those bolts are designed to take a lot of stress, and if the landing was hard enough, it might have happened even with the perfect 52 ft-lbs torqued in. In my experience, sometimes a bolt just fails and we blame ourselves because it feels easier than accepting bad luck. Your mileage may vary, but I've seen parts fail that were torqued exactly right, and nobody took the blame. Take this with a grain of salt, but don't beat yourself up over one sheared bolt when the landing was the big variable here.

emery1991mo ago

That's a good point... I've been there too, where you go over and over something in your head and just assume it was your fault. I remember once a buddy of mine had a control cable snap on his kit plane during a routine flight, and he spent weeks tearing himself apart over maybe nicking it during installation. Turned out it was a bad batch of cables from the supplier, but he'd already lost sleep for nothing. It's hard to tell the difference between a real mistake and just bad timing sometimes...