c/avionics-technicians

I used to think the new fiber optic crimpers were just a waste of money

We had a job on a G550 last month where we had to re-run a bunch of avionics bay data cables. My old metal crimper kept giving us a 3 dB loss on the tester, no matter how careful we were. The lead tech brought in his new plastic-handled one from a brand I'd never heard of, and our loss dropped to under 1 dB on the first try. It turns out the old one's jaw alignment was off by a hair, something you'd never see just looking at it. Has anyone else had a tool quietly go bad like that?

Had a GPS antenna connection corrode on a King Air after it sat for 6 months in a humid hangar in Mobile, Alabama.

It was a real pain to trace. The intermittent signal dropout was driving the pilots nuts. I ended up replacing the whole coax run and using a different sealing method on the BNC connector. What's your go-to for preventing corrosion on external antenna connections in coastal environments?

Tried using a dab of dielectric grease on a stubborn D-sub pin connector in a Cessna 172

Honestly, it stopped the intermittent fault for a week, but then the whole connector started reading high resistance. I learned that stuff can trap moisture if you use too much. Anyone have a better trick for those old, corroded pins?

Update: I was cleaning circuit boards wrong for years until a simple test showed me

For a long time, I used the same old aerosol contact cleaner on every avionics board that came through the shop. I figured if it worked on one, it worked on all. Then, about six months ago, I was working on a Garmin G1000 display from a Cessna 172 that kept having intermittent faults. After my usual clean, the problem came back in two days. My lead tech, Mark, watched me do it again and just said, 'You know that stuff can leave a film on some of these newer boards, right?' He had me use a specific cleaner, Chemtronics Flux-Off, on a small test area and then check the resistance with a meter. The difference was clear. The old cleaner left a measurable residue that was causing issues. I had been adding problems instead of fixing them. Now I always check the manufacturer's guidance first. Has anyone else run into this with specific avionics units?

Just read the FAA's new report on wiring faults and the numbers are wild

I was going through the latest FAA safety briefing and saw that over 40% of avionics system failures they tracked last year were traced back to wiring issues, not the black boxes themselves. That's way higher than I ever thought. We spend so much time on LRU swaps and software updates, but the real weak link is often the basic harness. Found it in their '2023 General Aviation Wiring Review' PDF on their site. Makes me think we should push for more time on continuity checks during inspections. How many of you actually do a full pin-to-pin on every annual, or just when there's a problem?

PSA: The new anti-static bags from that big supplier are not the same

Honestly, we got a batch last month and the material is way thinner now. I had a static-sensitive board get zapped right through one after three days in the shop. Has anyone else seen this and found a better supplier?

Heads up on those new composite airframe connectors from a job in Wichita

Three years ago we started seeing these lightweight composite connectors on a regional jet mod in Wichita. Last month, I had a bird strike repair where the composite housing on a main bus connector cracked from vibration, not the impact. It caused an intermittent power loss to a whole comms rack. The tech manual torque spec was fine for the pins, but the housing material couldn't handle the local flex. We ended up adding a custom support bracket. Has anyone else run into these composite parts failing in ways the old metal ones wouldn't?

Spent about $150 on a specific torque screwdriver for avionics work, and honestly, it's been a game changer for me.

The shift from paper to tablets in our Denver hangar was way faster than I expected.

Two years ago, our whole team was still using those big paper binders for all the maintenance manuals and job cards. Then management pushed hard for the AvPro digital system, and within about six months, everyone was on tablets. The biggest change I saw was how much faster we could look up a specific wiring diagram or AD note, maybe cutting search time from five minutes to thirty seconds. But I've heard some older techs at other shops say they still prefer paper because it's easier to mark up and doesn't have battery issues. Which side are you on, digital or paper manuals?

Just realized how many old 28V systems are still flying around after reading a fleet survey in Aviation Week

I was reading a fleet survey in Aviation Week that said over 15% of the regional turboprops we still service daily are running on the original 28V DC architecture, which seems wild when you think about all the modern avionics we're trying to integrate.

Finally got the hang of that stubborn autopilot test sequence

It was during a night shift in Tulsa, and the senior tech just said 'stop fighting the manual and let the system tell you what it needs.' I started watching the fault codes cycle in a different order and found the real issue in about twenty minutes. Anyone have a better method for the Collins AP-105 pre-flight check?

Was reading an old manual for a 737-200 and found out the original flight data recorder used a 1/4 inch steel wire that could survive a crash at 3,400 Gs.

I mean, that's a wild amount of force for something from the 60s, and it makes you think about how much the basic idea of 'keep the data safe' hasn't really changed, just the tech, right?

Vent: My old shop in Phoenix had us hand-write every single wire run sheet.

We spent hours drawing them out and checking them, but after a mislabeled harness caused a two-day delay on a King Air, the new foreman pushed for a digital system. Now we use a tablet app that auto-generates the sheets from the diagrams, which saves a ton of time but feels less hands-on. Has anyone else made a switch like this, and how did your team adjust?

Hot take: I finally gave up on my old crimp tool and the difference is night and day

I was fighting with a stubborn D-sub connector for like an hour last week, and my boss tossed me his new ratcheting crimper. Got a perfect crimp on the first try, no cold joints. Anyone else have a tool that just made a job click for them?

Appreciation post: I found a crazy old FAA document about wire insulation

I was digging through some old boxes at our hangar in Phoenix, looking for a spare connector, and I found a faded FAA advisory circular from 1978. It was all about wire insulation breakdown. The thing that blew my mind was a chart showing that certain older PVC insulations could lose over 60% of their flexibility after just 15 years in a hot, dry environment like ours. I always knew old wire got stiff, but seeing that specific number really hit home. It made me think about all the classic birds we work on that are pushing 40 years old. Now I'm way more careful when I'm moving bundles in those older airframes, especially around hot zones like the firewall. I'm not just looking for chafing anymore, I'm gently bending wires to check for that tell-tale cracking. Has anyone else come across this kind of old data that changed their daily check routine?

Finally got my A&P cert after 3 years of night classes

Honestly, I was ready to quit last month when the practical on the G1000 nav system had me stuck for hours. Anyone else have a cert test story that almost broke them?

My lead tech told me to check the harness for a chafe point, and he was spot on

I was working on a Citation XLS last week, chasing an intermittent fault on the left-side landing gear indication. The system would test fine on the ground but drop out randomly in flight. I was ready to start swapping the proximity sensors, which is a big job. My lead, a guy named Carl with about 20 years on me, walked over and just said, 'Check the harness run near the main gear pivot. Look for a chafe.' I pulled the inspection panel and sure enough, about three feet back from the sensor connector, the wire bundle was rubbing against a sharp bracket edge. The insulation was worn through on two wires. A bit of heat shrink and some proper clamping fixed it in an afternoon. Saved me a ton of time and the customer an unnecessary parts bill. Has anyone else had a simple piece of advice from a more experienced tech save a huge headache?

TIL a pilot's offhand comment about his old plane's wiring saved me a day of work.

I was at a small airfield in Bend, Oregon, finishing up a nav light fix on a Cessna 172. The owner, a retired airline guy named Frank, was just watching. He said, 'You know, on the old 150 I flew, the ground for that circuit liked to hide behind the panel support, right where the bundle turns sharp.' He was just making talk, but I checked. Sure enough, a green wire had rubbed through on that exact edge, shorting to the frame. It wasn't even the issue I was there for, but it would have failed a check. He didn't know the system, just remembered a quirk from flying it. How often do we ignore the guy who just flies the box? Ever had a pilot give you a tip that actually panned out?

Spent 6 hours chasing a phantom voltage drop on a G1000 install

It was a simple LRU swap on a Cessna 182, but the new unit kept throwing a power fault. My meter showed 28 volts at the connector pin, but the avionics bay was a mess of old splices. The real issue was a corroded ground strap under the panel that only showed up under load. Has anyone else had a ground path hide that well?

Had a pilot insist his autopilot was haunted because it kept pitching down at exactly 2,500 feet over Phoenix. I was ready to write him off until I found a single frayed wire in the static port heater circuit.

Spent a full shift chasing a weird static on a comms radio

Honestly, I had a Cessna 172 in the hangar with a complaint about faint static in the headset only during transmit. Checked the obvious stuff, antenna connections, coax, even swapped the radio head. Ngl, it took me six hours to trace it back to a tiny bit of corrosion on the shield of the audio cable where it passed through a firewall grommet. The plane had been sitting for a while and moisture got in. Has anyone else had a sneaky issue like that where the problem was just a few strands of wire?

I finally chose between a Fluke and a generic DMM for my kit

Went with the Fluke 87V after a coworker in Tampa said his cheap one gave a bad reading on a 28V bus. Anyone have a solid backup brand they trust for less?

Pro tip: I cleaned a stubborn D-sub connector pin with a fiberglass pen instead of contact cleaner and it left conductive debris that caused a new intermittent fault.

What's the best way you've found to clean those tiny pins without making a bigger mess?

PSA: I started logging every single wire I touched on a repair and it cut my rework rate in half

About six months ago, I was getting killed by callbacks on a CRJ-700 project, mostly for simple continuity issues I missed. I bought a cheap notebook from the gas station and forced myself to write down every wire number, connector, and pin I verified, even if it seemed obvious. Last week I checked my logs, and I've gone from maybe one callback every two weeks to just one in the last two months. It's annoying at first but now I feel naked without that notebook. Anyone else have a dumb simple habit that ended up being a game changer?

Finally traced a phantom static in a G1000 audio panel to a corroded pin in a connector under the copilot's seat after 3 days of chasing it.

What's your go-to method for tracking down intermittent audio faults that don't show up on a bench test?