Spent 8 hours chasing a ghost signal on a King Air 200 yesterday

Honestly I thought my tester was busted after the third time the nav display flickered. Turned out it was a chafed coax cable behind the overhead panel that only grounded out during turbulence. Took 8 hours across two shifts to find because the fault disappeared on the bench. The before and after difference was night and day - clean signal with zero dropouts after replacing the cable. Has anyone else had a similar gremlin that only shows up under specific flight conditions?

2 comments

2 Comments

matthew_owens91mo ago

Did a buddy of mine spend three days tearing apart a Cessna 172 once because the alternator only failed when the plane was banked hard to the right? Turned out to be a loose ground wire that looked perfect on the ground but wiggled free under G-load.

jamesmason1mo ago

Man those are the worst kind of gremlins, the ones that know exactly when to act up. I swear avionics gremlins have a union meeting every time you go to troubleshoot. Last month I had a Garmin 430 that would randomly reboot itself but only when you were 10 minutes into an approach and nobody was looking at it. Found out the cooling fan was barely spinning and overheating just enough to crash the unit after 45 minutes of operation. Still salty about the three trips I wasted chasing that one.