Had a power supply fail on a King Air last Thursday, learned a lesson about pre-flights

I was doing a routine check on a 2005 King Air 350 at our hangar in Boise and the whole avionics bus went dead when I powered up the test bench. At first I thought it was a bad ground somewhere in the harness, but after tracing wires for about 45 minutes I realized the main power supply unit had a cracked solder joint inside. It was one of those little things you'd never catch unless you actually opened the cover and looked. The funny part is the logbook showed it was swapped out only 18 months ago, so I guessed the replacement was a dud from the start. I ended up replacing it with a refurbished unit from a shop in Spokane and the bus came right back online. Has anyone else run into brand new parts failing like that on the bench before the plane even got airborne?

2 comments

2 Comments

perez.willow1mo ago

Those 18 month old replacements are sometimes the ones that fail the most.

rubyschmidt1mo ago

Exactly this. @perez.willow it's like when you buy a cheap toaster to replace the old one and it burns your toast within 3 months. Planned obsolescence everywhere now.