Third time this month I've seen someone terminate a cannon plug without using the backshell properly

I was doing a preflight check on a King Air 350 over at KSDL last Tuesday and noticed two pins already backed out on a DM3500 antenna cable. Pulled the boot back and sure enough no backshell, just heat shrink holding it together. How do you guys deal with people who skip that step? Seen it cause intermittent GPS dropout twice now.

3 comments

3 Comments

logan6581mo ago

Last month I found a Garmin GTX345R transponder antenna on a Cessna 441 with the same thing - good old heat shrink and zip ties doing the backshell's job. GPS loss every time we hit moderate turbulence, traced it straight to that mess. Five bucks says these guys are the same ones who think dielectric grease fixes everything.

jadej501mo ago

Used to be one of those guys who thought a zip tie fix was fine as long as it held. Then I saw a loose antenna wire short out a GPS antenna on a Baron, took forever to trace. Changed my whole view on proper backshells, theyre cheap insurance for sure.

ward.kim1mo ago

Ngl that Baron story hits close to home. Had a similar thing on a 172 where the GPS signal was dropping out in the pattern. Took me forever to find the coax had pulled loose from the crimp because someone used electrical tape instead of a proper backshell. Swapped it out with a proper connector and never had the issue again. Honestly the cost of a good backshell is nothing compared to the time you waste tracing intermittent failures. Dielectric grease is great for keeping moisture out of connectors but it won't fix a loose connection.