That buzzing sound on the ground power cart isn't always normal

I was doing a 767 battery service yesterday and kept hearing this weird hum from the ground power unit. My lead said that's just how the 28V carts sound when they're under load. Turns out he was wrong, it was a loose bearing in the cooling fan. The cart actually overheated about 20 minutes later and shut down. I only caught it because I walked around the unit instead of just standing in front of the panel. Has anyone else had a ground cart fail mid-test like that?

2 comments

2 Comments

abbychen8d agoMost Upvoted

Man that drives me crazy! Diana your lead was definitely wrong because overheating is never "normal wear and tear" on a ground cart. If it shuts down mid test that's a real safety hazard not just some quirky noise. I've seen carts catch fire when bearings seize up and that's way worse than a simple fix. You did the right thing walking around it instead of ignoring it like most people would. Always trust your gut when something sounds off even if the senior guy tells you it's fine.

diana1558d ago

Nah, that's just normal wear and tear, you're overthinking it. Ground carts make odd noises all the time, your lead was right.