Rant: Lost a whole afternoon because the torque spec sheet was wrong on a 737 flap track

Was out at KSNA last Thursday doing a flap track replacement on a 737-800. Got the old one off, new one lined up, started torquing the bolts per the IPC. About halfway through the sequence felt one bolt get way too tight way too fast. Checked the sheet again and it called for 350 inch-pounds on a bolt that should have been 200. Splitsville on that bolt head. Had to drill it out, retap the hole, whole job went from 4 hours to almost 7. My lead came by and said 'yeah that revision last month had typos on all the outboard track fasteners'. Nobody flagged it beforehand. Anyone else run into a bad spec sheet from a recent revision that cost you time?

3 comments

3 Comments

stella_murray16d ago

...and my lead just walks by after the fact like 'oh yeah that revision's been bad'... real nice timing on that one. I get what you're saying about feeling it out, but when you're on a 737 and the IPC is supposed to be the bible, you kinda expect it to not have random wrong numbers in it. Guess I should've just vibed the torque instead of using the calibrated wrench... next time I'll just close my eyes and tighten until it feels right.

tyler_wilson16d ago

Sounds like the real issue was you not verifying the torque spec before cranking on it. A quick double check against the manual wouldve saved you most of that afternoon.

sandra_anderson216d ago

I get what you're saying about checking the manual, but honestly, sometimes the manual doesn't match real life with older parts or aftermarket stuff. That's where experience comes in, not just trusting a book of specs. I've had plenty of moments where the "correct" torque stripped a thread or broke a bolt on something that should have been fine. Sometimes you gotta feel it out and know when to stop, even if the manual says something different.