Do I need to be an A&P to install intercom jacks?

[moparrob66]

Hello-

Im about to pull the trigger on a 172B. Its pretty squared away except theres only intercom jacks for the front. If I want to replace the ash trays with intercom plugs, do I need to pay an A&P or can I DIY?

FWIW, Ive wired lots of automotive abd household stuff and I've yet to let the snoke out of the wires.

Thanks always for the input!

 

[aterry1067]

Hello-

Im about to pull the trigger on a 172B. Its pretty squared away except theres only intercom jacks for the front. If I want to replace the ash trays with intercom plugs, do I need to pay an A&P or can I DIY?

FWIW, Ive wired lots of automotive abd household stuff and I've yet to let the snoke out of the wires.

Thanks always for the input!

You will need an A&P to sign off the install. If you are quite handy with wiring, you may find an A&P that will let you do the majority of the work while s/he supervises you and then signs off then install. If it’s a newer audio panel, the tray may need to come out so you can terminate the wires and plug them into the connector. If it’s an older panel or plain intercom, you can just solder them in to the copilot jacks and daisy chain the two rear sets. Either way, it will require an A&P to sign it off.


Edit to add: You may consider just getting a portable intercom extension that will let you plug in a couple more headsets, and see if or how often you really need jacks in the rear. Many of the online parts stores have portable intercoms for less than $300.

 

[Witmo]

The short answer is no. Installation of anything in a standard category aircraft is not among the approved list of owner/operator preventive maintenance actions. You can work under the DIRECT supervision of an A&P who will sign off the return to service under his ticket which makes him liable for legality of the materials used and the overall correctness of the work performed.

 

[Let'sgoflying!]

How would you connect the shielding on those wires? It’s something to consider, & might need done a specific way.

 

[moparrob66]

Looks like I can use a splitter to send two jacks to the back seat. Its kinda janky having wires all over the place but I like saving $2k (quoted estimate) more than I dislike the extension cords. Thanks for the input guys!

 

[Jim_R]

Looks like I can use a splitter to send two jacks to the back seat. Its kinda janky having wires all over the place but I like saving $2k (quoted estimate) more than I dislike the extension cords. Thanks for the input guys!

I hope you have better luck with splitters than I did. When I got my plane, it had a Sigtronics 4-place intercom, but only two places were wired. I bought a 3-way Y-splitter (aka a "W-splitter") and plugged it into the co-pilot position. Because of physics, the more headsets used, the less well it worked (sounds got softer for users, both transmitted and received). It was fine for just the copilot (no change), okay for the copilot and one backseat passenger, and unusable for all three simo. Based on that experience, I considered getting two Y-splitters and plugging one into each of the front two jacks, but while that would have "worked", it would mean that a passenger sharing the pilot Y-cable would cause my headset performance to degrade slightly, and it would also make that pax headset mic hot when I was transmitting on the radio. For me, those compromises were unacceptable.

I did a lot of the work on my plane as a new owner under the supervision of a friendly A&P who was willing to help a n00b learn about his plane. One thing I did back then was wire up the other two intercom positions "correctly", though in a DIY fashion. My A&P taught me how to use a metal brake to build a small box out of sheet aluminum. I mounted the two rear-seat jacks in this box, then mounted the box to the aft end of the center tunnel, up against the rear seat/spar carrythrough box. It wasn't pretty, but it worked well--way better than the W-splitter extension cord. Biggest annoyance with it was how it complicated removal of the tunnel cover to access that area for annual inspection work. Second biggest was that pax would sometimes bang their foot on it getting in/out of the space behind the pilot.


When I had my panel re-done a few years later, I had the shop install jacks in the rear sidewalls like a big-boy plane.