3 years ago at O'Hare I swapped the wrong LRU on a 737 and no one noticed

It was a Friday night shift in Chicago, I was exhausted, and swapped a transponder with a similar part number without double-checking the pin layout. The plane flew 12 more legs before someone caught it because it somehow passed all the tests anyway. Has anyone else had one of those "whoops" moments that just worked out?

2 comments

2 Comments

paul_lane8017d ago

Did that LRU have the same connector shell or something? A buddy of mine at United once swapped a VOR receiver for a glideslope receiver on a 757 because he was half asleep and the rack labels were smudged. Both units had the exact same part number prefix, but the first one had a different pin for the antenna. The plane flew for like three days and the pilots never noticed because they never tuned a VOR on that aircraft lol. He only found out during a lookback on his paperwork and had to call the chief pilot to beg them to check the logs.

-1

patricia_rodriguez17d agoMost Upvoted

Lol "never tuned a VOR" is wild but honestly not that surprising. Meanwhile the antenna pin thing is the real kicker, those LRU swaps hide so many tiny differences that get missed until someone's looking real close at a wiring diagram months later.