c/avionics-technicians

11

elizabeth_king•2d ago

Switched to torque wrenches with digital readouts for pitot tube installs

I used to just go by feel on pitot tube fittings for 8 years until I pulled one too tight and cracked a housing last spring. The digital torque wrench cost $400 but it beeps at the right setting so I don't overthink it. Has anyone else found a specific brand that holds up better on the flight line?

6

elliotr39•2d ago

The shift that wrecked me until I figured it out

I used to swear by the midnight shift for avionics work. Quiet hangar, no managers breathing down your neck. But last month we had a string of 4 back to back nights where every radio update went wrong. I spent 6 hours chasing a bad ground on a Garmin GTN 750 and almost missed the paperwork deadline. Then a senior tech named Dave told me he switched to days just to catch problems while the pilots are around. Took his advice last week and it felt weird at first but I caught a wiring issue on a King KX 165 before it even hit the bench. Has anyone else found that your shift choice really changes how clean your installs come out?

17

cole_davis47•2d ago

Hit 5000 flight hours on my bench scope last week

I was wiring up a new Garmin G3X install in a Cessna 182 and noticed my old Fluke scope meter clicked over to 5000 hours. Kinda hit me that I've spent that much time just staring at waveforms and chasing bad grounds in the shop. That's a solid 2 years of 8 hour days hunched over a bench. Most of those hours were on King radios and old Collins stuff from the 70s. Has anyone else kept track of their bench time like that or am I just weird?

6

miam11•3d ago

Got bit by a corroded pin on a D-sub connector yesterday

Was troubleshooting a comm fault on a King KX 165 and found 10 milliohms of resistance on pin 22 where the spec sheet says zero. Anyone else run into intermittent issues from corrosion that looked clean to the naked eye?

16

abbyc33•4d ago

I finally stopped using dielectric grease on every connector

Last month, a senior tech at my hangar watched me slather dielectric grease on a pitot-static connector and told me to stop. He said I was trapping moisture by using it on sealed connectors, not preventing corrosion. I argued but he showed me three failed probes from the last year that all had grease holding water against the pins. So now I only use it on exposed battery terminals and leave the sealed plugs dry. Has anyone else been overusing this stuff without realizing it?

4

henrygrant•6d ago

Shoutout to the old timer who caught my crimp mistake at SEA

I was working a line maintenance shift at Seattle-Tacoma last March re-pinning a D-sub connector on a CRJ-200. Some retired Air Force avionics guy, probably 70 years old, just watched me from the doorway of the avionics bay for a solid two minutes. He walked over and asked me if I actually checked the pin retention force before closing the backshell. I hadn't, figured it was fine since the crimp looked clean. He pulled out his own pin extraction tool and showed me three pins in my connector that would have vibrated loose within 50 flight hours. He said something like "the wire ain't married to the pin till you feel that click." I've never skipped a pull-test since then, and I check every single pin in a connector no matter how rushed I am. Any of you guys have a mentor moment like that where someone saved you from a dumb mistake?

2

the_mary•6d ago

PSA: Spent $400 on a cheap o-scope from Amazon and it lied to me for 3 weeks

Chased a ghost in a King Air 350 for three weekends straight before I realized the scope was reading a half volt low on the 5V reference bus. Anyone else get burned by cheap test gear or am I the only one who learned this lesson the hard way?

21

elizabeth_king•6d ago

Got locked in an equipment bay for 45 minutes at O'Hare

Last month I was swapping out a comm unit on a 737 at ORD. Crawled into the forward equipment bay to trace some wiring. Door slammed shut behind me. The inside handle was broken off. Nobody could hear me over the APU and ground power. I had to pop the emergency release panel with a screwdriver. Took forever because my phone had no signal down there. Now I always check the door latch before I go into any bay. Has anyone else gotten trapped in a tight spot like that?

2

jenny580•7d ago

Found a game changer for cleaning ancient corrosion off connectors

Had a box of old MIL-SPEC connectors from a 727 that looked like they'd been sitting in salt water for years. Contact cleaner and a brush barely touched the green crust. Out of desperation I tried a diluted vinegar soak for 5 minutes, then hit them with compressed air and dielectric grease. It got the pins clean without damaging the plating. Has anyone else used household stuff like that in a pinch on stubborn avionics hardware?

1

bettyk53•7d ago

Can we talk about the connector that failed on my bench today?

I was testing a nav radio on a King KX 165 and the D-sub pin pulled right out of the solder cup after less than a year, so has anyone else had trouble with those cheap pre-assembled harnesses from the supply house?

3

emerychen•8d ago

Switched to a different pin crimper last month after 6 years on the same old one

I used to just use the basic crimper from the tool crib for everything, but after a batch of 20 pins failed continuity on a Cessna 172 harness, I grabbed a Daniels DMC crimper. Anyone else notice a big difference switching to a higher end crimper for those tiny gauge wires?

1

palmer.zara•8d ago

5 years of crimping D-Subs wrong and nobody caught it

Found out last Tuesday I’d been using the wrong die on my crimper for DB9 pins this whole time. Only figured it out when a senior tech pulled a pin out by hand during a continuity test lol. Anyone else ever have a basic habit go unnoticed forever?

7

cameron684•8d ago

Found out my old shop's wiring was 30 years past its life expectancy

Honestly I was going through some old manuals from a place I worked at back in 2002 and stumbled on a maintenance log. Turns out the main harness in the Cessna 172 we used for training had been installed in 1974 and was rated for 15 years max. I called my old boss about it and he just laughed and said they replaced it last year finally. Has anyone else run into ancient wiring that slipped past inspections?

12

wren826•13d ago

Rant: wasted $180 on a 'certified' power supply tester that was totally off

I bought this supposedly top-of-the-line tester off a guy on Facebook Marketplace for a Cessna 172 I was diagnosing. Turns out it was reading 14.2 volts when the bus was actually at 12.8, and I chased a phantom alternator issue for three days. The seller swore it was calibrated last month, but I bet he just printed a fake sticker. Has anyone else gotten burned by used test gear that wasn't what it claimed to be?

29

kai_bennett•14d ago

Hit 1000 pin repairs last week and it finally clicked

I was logging a harness repair on a 737 NG and noticed my count hit an even 1000 pin repairs. That's like a decade of digging out stuck pins with a tiny hook tool and re-crimping them. Has anyone else kept a tally of a random task that adds up way faster than you'd think?

6

jesse_cooper•14d ago

Took me 3 years to realize I was crimping Cannon plugs wrong

I was over at the hangar in Memphis last Thursday and my coworker watches me crimp a size 16 pin and just goes 'you know you're supposed to use the red hole for that, right?' I'd been using the blue hole on my M22520/1-01 the whole time. Three years of crap connections and I never figured it out. Anyone else have a basic tool epiphany that made you feel like an idiot?

19

white.alex•14d ago

Had a GPS antenna fail mid-flight over Phoenix last month

I was on a King Air 350 coming back from a maintenance test flight near Phoenix when the copilot's GPS unit went completely dark. No warning flags, no error codes on the MFD, just a blank screen where the position data should be. We landed fine using the other unit, but after I pulled the antenna off the roof I found water had gotten into the coax connector and corroded the center pin. The sealant around the base looked fine from the outside, but a tiny crack let moisture in after a heavy rain the day before. I ended up replacing the antenna and repotting the connection with new sealant, then ran a full GPS ground check for 30 minutes. Has anyone else seen water sneak past a good looking seal on these older King Air antennas?

9

emerychen•15d ago

Overheard a veteran tech say something at PDX that stuck with me

I was working a line in Portland last week and heard this old timer tell a new guy that most avionics failures are just bad connections, not bad boxes. He said he's fixed more planes with a can of contact cleaner than with a test set. How do you guys decide when to chase a wire versus just swapping a LRU?

-1

gavin_clark•15d ago

Why does nobody talk about how bad the lighting is in most hangar bays

I was working on a CRJ900 at a regional hub in Memphis last night and could barely see the pin connections on the back of a PFD. My headlamp kept dying and the overhead fluorescents flickered so bad I almost missed a bent pin. Any of you guys swap out the hangar lights yourself or just deal with the headache?

17

joseph_coleman•16d ago

Had a connector pin back out mid-flight last Tuesday

I was troubleshooting a glideslope fault in a 737 at KORD when I pulled the rack and found a pin that had backed out maybe 1/8 inch. Re-crimped it with a new M22520 tool and the fault cleared right up. Anyone else had one of those moments where you knew the schematic was lying to you?

18

hayden587•17d ago

Unpopular opinion: that 'no smoke no fire' philosophy on Garmin 430s is going to cost someone a plane

Had an intermittent display flicker on a 430W last Tuesday during a run-up, took it apart and found a cold solder joint on the power rail that would have never shown up if I just waited for visible smoke before pulling the unit.

6

richardknight•18d ago

First time I did a full pitot-static test and nearly flunked it

I was testing a Cessna 172 at a small shop near Phoenix last month. Got through the altimeter checks fine but the vertical speed indicator was reading way off. Spent 45 minutes checking for leaks before realizing I left the test set valve cracked open a quarter turn. My lead tech walked over and pointed it out in about 10 seconds. Felt like an idiot but learned to double check all fittings before starting. Has anyone else had a simple mistake waste their time on a system test?

17

nancy_davis•21d ago

Found a trick for tracing intermittent faults on 737s without a wiring diagram

After 4 hours chasing a flickering landing light on a 737NG last Tuesday, I tried clamping my multimeter lead to a long piece of mechanic wire and running it along the bundle to pick up the break by sound, and it worked on the first try, has anyone else used this method on older Airbus models?

13

allen.cole•24d ago

Had a GPS antenna fail on me mid-flight yesterday

I was flying a King Air 350 out of Boise yesterday and lost GPS signal about 20 minutes into the flight. The MFD started showing a red X over the position data, and the FMS went into dead reckoning mode. I had to fall back on VOR and DME for navigation, which worked fine but really slowed things down. After we landed, I checked the antenna and found a crack in the housing where moisture had gotten in. Corrosion ate through the coax connection, and it finally gave out. I replaced the antenna with a new WAAS unit and resealed the base with fresh sealant. Has anyone else seen these older antennas crack like that after a few years in service?

14

victor219•26d ago

G1000 screen flickered out during preflight this morning

I was doing a routine preflight on a Citation Mustang around 7 AM, and the PFD just started flickering like crazy before going dark. Tried the usual reset cycle with the avionics master, no luck. Ended up pulling the LRU and reseating the backplane connectors, which fixed it for now, but I'm not confident it'll hold. Anyone else seen this on the G1000 NXi systems or is it just mine that's acting up?