c/avionics-technicians

Called out on my crimp terminals after 5 years in avionics

Always did the tug test on my crimps. Thought that was enough. Then a quality inspector named Pete at a shop in Denver showed me his microscope. Had nicks and fractures I never saw. Turns out I was using the wrong die size for the wire gauge. Felt like a complete idiot. Anyone else get humbled by a QC guy?

I finally figured out why my Garmin GNS 530 was losing signal mid-flight

Spent 3 hours troubleshooting a GNS 530 that kept dropping GPS signal on a Cessna 172 last Tuesday. Checked the antenna, the coax, even reseated the connectors twice. Finally found a cracked ground terminal on the back of the unit after a 4th continuity test. Anyone else wasted a whole afternoon on something this simple before?

That LRU swap that turned into a 4 hour nightmare over one connector pin

I was working a comms issue on a King Air out of Van Nuys last month and figured it was a bad VHF radio unit. Pulled the old one, slapped a fresh LRU in, and the problem was still there. Wasted a good hour double checking power and ground before I finally broke out the pin extraction tool. Found a single pin in the backshell connector where the retaining clip had collapsed on the last guy's install. It looked fine visually but had no actual contact. Another 45 minutes to extract, replace, and verify that stupid pin. Four hours total for what should've been a 30 minute swap. Has anyone else seen these mil-spec connectors fail internally like that? I'm starting to carry spare contact pins in my tool bag.

Warning: 3M part number label peel-off nearly grounded a CRJ-700

Had a weird one happen last Tuesday in Omaha. Was working on the weather radar system in a CRJ-700, and a 3M label with the part number for a PDU just peeled right off in my hand. I'd been reaching around to check a connector, and the label stuck to my glove then came off clean. Took me 45 minutes to figure out which part was which by cross-referencing wiring diagrams. Has anyone else had those labels fail like that in cold hangar temps? I'm thinking of using a clear coat spray on them going forward.

I finally changed my mind about digital panel meters after a chat with a old Navy tech

Ngl, I always swore by analog gauges for troubleshooting. Then last week at the shop in Tucson, this retired Navy guy showed me how his Fluke digital meter caught a intermittent fault on a Garmin G1000 that my Simpson analog couldn't see. He said, 'Your eyes miss the glitch, but the digits don't lie.' That got me thinking about whether digital is actually more reliable for modern avionics. But I still worry about ghost voltages and false readings on digital screens. What do you guys use for sniffing out those random dropouts in the cockpit?

Old timer at work told me to trust the circuit breaker and not the multimeter

Honestly, I was testing a bad landing light circuit last week and kept getting 12 volts at the connector. My buddy Mike, who's been doing avionics since the 80s, said 'check the breaker again even if it's not popped.' I thought he was crazy because I already pulled out my Fluke and it was fine. Turns out the breaker was weak and tripping under load at 8 amps instead of 15. Has anyone else dealt with a breaker that shows good voltage but fails under a load?

Hit 10,000 hours on my Fluke 87V last week

I was doing a routine check on a Garmin G5000 at the hangar in Tucson when I glanced at the meter and realized it had logged over 10,000 hours of use. That thing has been through three drop tests, a coffee spill, and one time a mechanic stepped on it. It still reads within spec, which honestly surprised me given how hard I am on gear. Anyone else have a tool that just won't quit no matter what you put it through?

Talked to a 30-year vet who said my troubleshooting was backwards

Was working on a King Air 200 at the hangar in Wichita last Thursday and this old timer walked over while I was chasing a nav fault. He watched for like 5 minutes then said 'you're looking at the box first, but the wires fail way more often.' Handed me a schematic and pointed to a connector at the wing root that had corrosion I'd missed completely. That conversation made me totally rethink my process for avionics faults, and I've been doing this for 12 years. Anyone else ever get humbled by someone who just knows the common failure points better?

Blew $150 on a bad coax cable tester last month

I picked up that HST-3000 knockoff from an online surplus place for fixing a Cessna 172 radio issue. The thing kept giving false readings on the antenna coax, so I spent three days chasing a problem that wasn't there. Turns out the tester itself was junk and I could have just used a multimeter and a known good cable. Has anyone else run into fake test gear that wasted their time?

Warning: almost fried a whole panel on a King Air 350 last week

Was troubleshooting a flickering display on a King Air 350 at KAPA and accidentally clipped a 28V line with my meter probe while the battery was still hot. Smoke started coming from the PFD - had to pull the breaker and yank the battery quick before the whole thing went up. Anyone else ever had a dead short smoke a display on these?

Bought a $600 O-scope from a surplus sale that turned out to be a paperweight

That engineer on the ramp last Tuesday wouldn't let me touch his G1000

I was swapping a pitot probe on a King Air at KSDL and this fresh engineer from Cessna kept hovering telling me not to break the glass cockpit wiring. He literally stood there for 45 minutes watching me crimp three connectors and said I was doing it wrong even though Ive done this 100 times. Has anyone else dealt with factory reps who act like you've never seen an airplane before?

Tried a Fluke multimeter vs a cheap no-name one for a tricky 737 troubleshooting job

Had a weird intermittent fault on a 737's pitot heat system last Wednesday. Grabbed my usual cheap meter from the truck, got all sorts of wonky readings that made no sense. Swapped to a Fluke 87V my buddy loaned me and traced the issue to a bad relay in 10 minutes. The cheap meter was picking up noise from the AC bus. How often do we chase ghosts just because of bad gear?

Had a display go dark on me mid-flight last Tuesday, traced it to a corroded connector on a 3 year old screen.

Just realized I've been using the same oscilloscope probe for 12 years

Checked the calibration on my old Tektronix probe yesterday and it was off by 15% on a 400 Hz trace, so I swapped it out and now I'm rechecking every repair I did for the last 6 months, has anyone else had a tool like that drift without you noticing?

I finally found a weird wire that was causing intermittent GPS dropouts

Spent all morning tracing a fault on a Cessna 172 that kept losing GPS signal mid-flight. Turns out a chafed shield wire was grounding out against a canopy frame, and I only caught it after my third continuity test with a Fluke 87V. Has anyone else dealt with phantom grounding issues that took forever to track down?

Old timer at the hangar taught me more in 10 minutes than 2 years of school

I was swapping an LRU on a CRJ last month at Huntsville and this guy in his 60s walks up, no badge, just watching. He points at my connector and says "you're gonna pinch that gasket, kid." I blew him off at first. He showed me how to hold it at a 45 degree angle and spin it in instead of pushing straight. That little trick saved me a leak check that would've taken an hour. Anyone else had some random older tech drop knowledge on them like that?

Spent $400 on a fancy multimeter that claimed to read capacitance in-circuit and it lied to me every time

Had to pull three boards from a King Air last week before I realized the meter was giving me garbage readings on caps that tested fine with a manual discharge and check has anyone else found a handheld that actually works for in-circuit testing?

Debate: Multimeter probing technique - back probe vs pin insertion?

I used to always back probe connectors with a T pin, but after damaging a few Weather Pack seals I switched to using a small pin insertion tool through the wire side. Which method do you guys trust more for reading stable values without ruining the connector?

Had to choose between a Fluke and a Brymen meter. Went with the Brymen.

Picked up a new multimeter last week. My old Fluke 77 finally died after 15 years. I was gonna just buy another Fluke, but a buddy at the hangar talked me into the Brymen BM235. Said it's what Dave Jones uses. Honestly I was skeptical since it's half the price. But after tracing a weird intermittent fault on a G1000 harness, I'm glad I switched. The peak hold function caught a glitch the Fluke would have missed. Has anyone else made the jump from Fluke to something else and regretted it or been surprised?

Vent: My old bench power supply finally gave out after 4,217 hours

I was running a long test on a G1000 nav unit and the voltage just dropped to zero. Checked the log on the unit, and it had exactly 4,217 hours of runtime. I bought that thing used from a guy in Phoenix like eight years ago and never thought to track the hours. Kinda wild to see a piece of gear hit a hard stop like that. What's a solid, not crazy expensive replacement you guys would go for?

Changed my mind about those cheap crimpers from the online marketplace

I bought a set for $45 thinking I'd save cash on a quick job... ended up with a bad crimp on a D-sub connector that took me three hours to trace and redo. The tool just didn't hold the pin right, and I had to eat the labor cost. What's a solid crimper brand you guys actually trust for avionics work?

Chat with a retired FAA guy at the diner made me double check my work

I was grabbing a coffee at the Skyway Diner near the airport yesterday and got talking to this older guy, Bill, who used to be an FAA inspector. He said something that stuck with me: 'You know, most of the write-ups I saw weren't from broken boxes, but from techs rushing the paperwork and missing a simple step.' He told me about a case where a comms issue was just a loose BNC connector someone signed off as 'checked.' Now I'm going back over my last three jobs, especially the Garmin G500 install I finished Friday. How do you guys make sure you don't get complacent with the routine checks?

The weirdest before-and-after on a King Air's transponder I've ever seen

Last month, this thing was giving us a perfect, solid reply on the bench test, but after we reinstalled it in the bird, the signal strength dropped by over 30% for no clear reason. We finally traced it to a single, slightly-corroded BNC connector in the antenna feed line that must have gotten jostled during the reinstall. Has anyone else had a connector pass a bench check but fail the moment you put real flight loads on it?

I've been crimping D-sub pins with the wrong tool for YEARS and only found out when a new guy at the hangar asked why my crimps looked 'sad'.

He pulled out his own tool, a genuine PA-09 I'd never seen before, and showed me the perfect crimp in about 15 seconds, which made my whole collection of slightly-crooked connectors look completely amateur.