PSA: A bad ground in the tail cone took me 4 hours to find

Last week I was chasing an intermittent COM 1 dropout on a Cessna 172. I must have pulled and reseated every connector in the panel, swapped radios, even checked the antenna coax twice. Turns out a single screw holding the ground block near the tail cone was loose and I overlooked it because I assumed it was fine. Anyone else spend way too long on something simple that a fresh set of eyes could have caught in 10 minutes?

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lisa8204mo ago

The ground block being loose in the tail cone is a classic. I had a similar issue on a Cherokee where the strobe light would cut out randomly. Spent a solid afternoon checking the power supply and even replaced the flasher unit. Poked around the tail cone ground bar out of desperation and one of the nut plates was just spinning. A dab of locktite and a new washer fixed it faster than I want to admit. Sometimes you get so focused on the fancy avionics you forget the simple stuff is just as likely to cause problems.

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karenf404mo ago

Wait, you had a nut plate that was just spinning in the tail cone? That's insane. I honestly don't know how you kept your cool for a whole afternoon with that strobe cutting out, @lisa820. I would have been pulling my hair out after the first hour of checking the power supply. It's always the dumbest stuff that gets you, like a loose nut plate. I bet you felt pretty dumb for not checking the grounds first, but hey, we've all been there.

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