Found a hidden wiring error on a 737 that saved us a grounding

Last month at my shop in Atlanta, I caught a chafed bundle behind the FMC bay that would've shorted the weather radar. The old prints didn't show that routing change. Has anyone else run into bad updates from the service bulletins?

2 comments

2 Comments

samw4724d ago

Oh man, I gotta push back a little here. I mean, service bulletins exist for a reason and they're usually based on engineering analysis and fleet data, not just some guesswork. @karenlane, I get where you're coming from, but I've seen plenty of cases where following the bulletin exactly would've caught problems that ground truth missed entirely, like that time a mechanic's "improvement" introduced a hidden stress riser that later caused a crack. The chafed bundle sounds bad, but maybe the routing change was legit for a different reason like avoiding a known vibration issue on later models, and the real culprit was just a bad install or a missing inspection step.

karenlane24d ago

Has this been happening more often lately with these bulletins? I swear some of the updates feel like they were written by someone who's never actually been under a panel. That chafed bundle thing is scary because it's one of those issues that doesn't show up until you're already in the air and something fails. I had a similar scare on a different model where the bulletin said to reroute a harness but left out a crucial tie-down point, and it ended up rubbing against a bracket. Ground truth always beats what's on paper, at least from what I've seen.