c/avionics-technicians

Tried a digital torque wrench on harness pins - was wrong about them

I always used a beam style torque wrench for pin contacts. Figured digital was just overengineered nonsense. Last week I borrowed a Snap-on digital one from a buddy in Atlanta to check some cannon plugs on a King Air. It caught three pins I was under-torquing by about 5 inch-pounds. Now I get why the digital ones cost more. Anyone else had a tool they resisted then found out it actually works better?

Caught a cold solder joint on a Garmin G5000 display yesterday before it left the bench in Dallas

Had a pilot come up and say the PFD was flickering on descent, traced it to a pin that looked fine but had a hairline crack under the magnifier, resoldered it and ran the full avionics bus test twice after, anyone else run into intermittent issues that only show up with temperature changes?

Got called out for using a multimeter wrong on a Citation 560XL yesterday

Honestly, I've been doing avionics for 7 years and I always used the continuity beep to check wiring. An older tech showed me I was getting false readings because I wasn't isolating the circuit properly. He walked me through why you gotta use resistance mode with the circuit dead and disconnected. Has anyone else had to unlearn bad habits they picked up early in the trade?

Call me crazy but using silicone dielectric grease on avionics connectors is asking for trouble

I had to re-pin a whole harness last month because some previous guy packed the connector full of that stuff and it caused intermittent shorts in the landing light circuit, so why are people still recommending this when a dry connection or a dab of corrosionX works fine without the mess?

Hit 500 wiring terminations in one shift and nobody cared

Was working on a Hawker 800XP last month and counted 512 D-sub pins I crimped and soldered in a 10 hour day. My lead just said 'about average' and walked off. I expected at least a nod for that number since most guys top out around 350. Has anyone else hit a personal record that got ignored on the line?

Best day I ever had troubleshooting a 737 autopilot - zero maintenance write-ups for a whole shift

Blew $800 on a GPS antenna tester that told me nothing useful

Spent 3 hours chasing a bad coax on a Cessna 172 only to find the tester itself was giving false readings, has anyone else dealt with garbage calibration from those handheld units?

That line in the wiring diagram that said 'see note 4' cost me 3 hours

I was working on a 2008 Gulfstream G450 at the shop in Phoenix last Tuesday. Note 4 just said 'refer to vendor manual' but didn't say which vendor or where the manual was kept. Eventually found it buried in a PDF on an old laptop under the bench. Has anyone else run into diagrams that send you on a wild goose chase like that?

Hit exactly 500 flight hours on my bench testing yesterday

Was working through a backlog of comm radios and my logbook showed I passed 500 hours of bench testing time. That number surprised me because I only started this role 8 months ago in Phoenix. Anyone else keep a rough count of their bench hours or just me?

Question about using dielectric grease on D-sub pins

Honestly, I always used the standard stuff from the hardware store on connector pins, but last month I tried the specific aviation grade dielectric grease from Spruce. The difference in how smoothly the pins seated and how much more secure the connection felt was night and day. Has anyone else made that switch and noticed the same thing?

Hit 500 line replaceable units this year without a single callback

I just counted up my LRU swaps for the year and it came out to 500 exactly. That number surprised me because I had to bench test a faulty APU controller on a King Air last week that took three hours to pass. Any of you guys track your swap numbers and callback rates to see where you stack up?

Had a client insist on using a 20 year old GPS unit for an IFR approach

Guy brought in this old Garmin 430 that hadn't been updated since 2009. Told him the database was stale and he'd fail a checkride. He got all defensive, said he knew the area by heart. Flat out refused to pay for the update. I showed him the expired approach plate symbols on the screen, and he still argued with me for 15 minutes. Has anyone else dealt with a pilot who thinks they're above the tech?

Changed my mind about spending $400 on a test set after a veteran tech talked to me

I used to think you could get by with just a multimeter and a cheap oscilloscope for most avionics work. Then a guy named Jerry who's been doing this since the 80s pulled me aside at a hangar in Phoenix. He said 'son, you're gonna waste three days chasing a fault that a decent test set will find in 20 minutes.' I blew it off at first, figured he was just trying to sell me on old school gear. Last month I spent 10 hours trying to trace a intermittent comm issue on a King radio using my basic tools. Finally borrowed a buddy's IFR 4000 and found the problem in under an hour. That experience made me realize Jerry wasn't gatekeeping, he was saving me time. Has anyone else had a senior tech give advice that actually cost you money but saved your sanity? I'm curious what test sets you all actually use for troubleshooting analog stuff.

Old timer told me to check my crimp tool calibration every month - I thought he was joking until last week

I've been crimping D-sub pins for 7 years and never once checked my tool. Then this old guy at the hangar in Houston kept saying 'calibration drift is real on those things'. Took it in last Wednesday and the gauge was off by 0.003 inches. That explains why I had 3 intermittent pin issues on the same harness last month. Anybody else ever had a crimp tool go out of spec on them?

Found out the hard way that grounding my workbench actually fixed my weird voltage readings

Had a Cessna 172 pitot-static showing erratic numbers last month, swapped every sensor with no luck. Tried running a dedicated ground wire from the bench to the airframe ground and the readings went rock solid. Anyone else run into phantom issues from bad grounding on the bench?

Hit 150 knots on the bench and my harness swap clicked

I used to think pinning out a harness was just a waste of time if the wiring diagram looked clean. Got a CRJ 200 that kept throwing a flap skew fault, spent 3 days swapping cards and chasing grounds. Turned out I had a pin pushed back halfway in the connector from a previous repair, wasn't even making contact. My lead told me to ohm it out from end to end, I laughed and said the schematic says it's fine. He grabbed me and walked me to the bench, we jumpered it up and the fault came right back with a resistance spike at 150 knots simulated. Now I pin out every harness before I even look at the box, saved me 8 hours this week on a 737 autobrake issue. Anyone else have a moment where a simple continuity test caught something huge?

Switched my mind about thermal paste after a 5 degree difference

I used to think any old thermal paste was fine for avionics boards. Last month I had a GPS receiver that kept throwing errors in the shop here in Phoenix. I cleaned off the old crusty stuff and put on a name brand paste I ordered from DigiKey. Dropped the core temp from 78 to 73 degrees Celsius after a 20 minute run. That 5 degree change stopped the intermittent lockouts completely. Now I actually measure the spread and don't just glob it on. Anyone else seen big swings from just swapping paste on flight hardware?

Not sold on the whole 'always use digital multimeters' trend I keep seeing here

Been doing avionics for about 12 years now, started at a shop in Phoenix. I swear my old analog Simpson 260 catches intermittent signal drops way better than any Fluke I've tried. Digital meters just seem to average out the noise and miss those quick flickers in the cockpit wiring.

Rant: That conversation with a senior tech made me feel dumb about wire repairs

Was talking to Dave from our Dallas hangar last week, he's been doing avionics since the 80s. He told me I'm overthinking my cold solder joint repairs, that I should just cut and re-pin instead of trying to reflow everything. Hit different because he showed me a bundle he did in 3 minutes that would've taken me 20. Has anyone else had a senior guy call out a bad habit you didn't know you had?

Had a weird GPS dropout over Phoenix last week that almost cost me a flight check

I was doing a post-install check on a Garmin GTN 750 in a Cessna 172. Everything looked fine on the ground, but about 15 minutes into the flight test, the GPS signal just dropped for a solid 30 seconds. No warning flags or anything. I landed, pulled the antenna, and found the coax cable had a tiny pinch where it passed under a seat rail. Not enough to short it, but enough to mess up the signal at altitude. Took me an hour to find it with a cheap VSWR meter. Has anyone else dealt with intermittent GPS dropouts that traced back to a dumb cable pinch like that?

PSA: That fancy digital torque adapter at Oshkosh wasn't worth it for me

I was at AirVenture in Oshkosh last July and dropped $200 on one of those digital torque adapters everyone was raving about. Seemed like a no-brainer for troubleshooting panel screws and control cable bolts. But after three weeks on the job, I had to go back to my old beam-style wrench. The digital one kept giving me readings all over the place, especially when I was working in tight spots under a dash. I checked it against my calibrated wrench three times, and it was off by 5 foot-pounds each try. Maybe it was a bad unit, but I'm not chancing that on a flight control system. Anyone else ditch a fancy tool and stick with the old standby?

Found a hidden wiring error on a 737 that saved us a grounding

Last month at my shop in Atlanta, I caught a chafed bundle behind the FMC bay that would've shorted the weather radar. The old prints didn't show that routing change. Has anyone else run into bad updates from the service bulletins?

PSA: That $40 multimeter from Amazon nearly cost me a repair ticket

Last month I bought a cheap autoranging multimeter off Amazon for about 40 bucks. I figured for basic continuity checks and voltage readings it would be fine for my bench work. First time I used it to trace a bad pin on a Garmin G5000 harness, it gave me a false reading that sent me down a 2 hour rabbit hole. Turned out the meter was reading 0.5 volts high on DC. That little mistake could have gotten me flagged for a bad repair if I hadn't double checked with my Fluke. I ended up giving the cheap one to my buddy for his home garage projects. Has anyone else had a cheap tool bite them in the ass on a job?

Still don't get the obsession with fiber optic scopes in our line of work

I was out at a regional hangar in Wichita last Wednesday helping a buddy trace a flickering nav light on a King Air 200. Every other tech there popped out a $600 borescope looking for chafed wiring inside the wing root. I spent 20 minutes using a dental mirror and a shop light from three different angles and found the cracked insulation right where it passed over a stiffener. They all laughed until I had the fix done while they were still fussing with camera angles. Am I the only one who thinks we lean too hard on expensive inspection tools when a simple mirror and patience does the same job?

TIL that crimping D-sub pins wrong can cost you a 3 hour rework session

Honestly I just found out that I've been using the wrong crimper die size for my DB9 pins for like 6 months. One bad pull test on a production harness and I had to redo 15 lines. Has anyone else had a similar issue with cheap crimpers from Amazon?