Fix, Simplify or Start Over?

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DenverDave

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I'm not an avionics tech but after giving my avionics a good visual inspection there are a lot of problems.

My panel is typical junk:
King KMA 20 TSO audio panel
(When listening to com 1 on phones you can faintly hear com 2)
Narco MK12D replacement for a field-installed RT308
(Nav INOP, glass on ARC IN-525A indicator loose, connector on KN-75 GS receiver broken/loose. Low range for com transmissions.)
TKM MX12 replacement for a field-installed MK12
(Nav INOP, low range for comm transmissions.)
ARC 300 ADF
(INOP)
King KT78 transponder, Tailbeacon ADSB
(Works)
SPA-400 Intercom
(Can't transmit with intercom off even though manual says you can)
Remote ARC marker beacon system in addition to the KMA 20
(Obviously INOP)

And not to mention the ungodly mess that a half dozen independent avionics installations have caused. Wire security is weak, stuff touches the yoke "Y" when at full travel and remote boxes are loosely stuffed in every spot imaginable.

I'm VFR-only although I'd like to be IR. IR is more of a pipe dream at this point.

If the nav stuff is dead forever I'd probably just prefer it wasn't on board. If I was paying for labor of removing all the useless nav junk and fixing the comm issues maybe I'd be better off pulling it all and installing something clean and simple like a GTR 225 and a GTX 327.
 
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If you were reasonably certain you were going to be VFR forever, I'd say simplify. But since you mentioned IR, I'd start over.

Wipe everything clean and then put these 4 items the stack:
  • PS-Engineering audio panel, either something from the 8000 series or PMA450b
  • Garmin GNX375
  • Garmin GNC255
  • Another GNC255 or one of
    • Garmin GTR225
    • Garmin GTR200
    • Trig TY96A
    • Trig TY97A
I'd also add the CDI version of the GI275 to replace the IN-525A
 
Haha yeah this wouldn’t be a good avionics thread without $70k of Garmin and $35k of Cessna.

It’s an obviously worn out Skyhawk with lots of other small but plentiful issues. At this point I’m just trying to be a safe VFR pilot. I saw a YouTube video of a guy with a similarly problematic Mooney that went through a Charlie without actually talking to anyone. One way or another the comm issue needs to get fixed.

A 172 doesn’t seem like a great IFR plane in the western US plus limited need so I probably wouldn’t use IFR capability beyond getting the rating.
 
I'm a big fan of simplicity. If the airplane is VFR only then I'd just spend money on one good com radio and a transponder. Many of the com radios available today have intercoms built into them.

But if the goal is to have an instrument capable airplane you're obviously going to need a bit more than that. Again, I prefer simplicity. I'd pick some audio panel with a built in intercom (probably a Garmin or PS Engineering), a GTN 650 or 750, a second nav/com radio such as the GNC255, and a transponder.

I likely wouldn't reuse anything except maybe the tail beacon. You could possibly do the upgrade in stages, such as installing a GNC255 now and saving for some of the other components. The 255 has a two place intercom built in that could be used for the time being if you wanted or needed to.
 
How about dual G5 with accessories and GNC 355 + any PMA audio panel. That takes care of everything urgent.
 
CA182R said:
How about dual G5 with accessories and GNC 355 + any PMA audio panel. That takes care of everything urgent.
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He'd still be without a NAV radio (VOR/LOC). And the G5's are overkill if his IR really stops and ends at passing the checkride. If everything else is coming out, no sense in sticking with the KT78 transponder. At that point the GNX375 would be cheaper.
 
DenverDave said:
Haha yeah this wouldn’t be a good avionics thread without $70k of Garmin and $35k of Cessna.
Click to expand...

I've seen this kinda thing all the time here in the deep south with autos ... $1,500 car with $5,000 in amps and speakers! o_O
 
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Might want to look at Dynon. If you need IFR then you’ll need something Garmin flavored, but I think you can drop a Skyview HDX in there, can’t you?
 
Play with 3 audio panels (Garmin, PSE, Avidyne). Rank your favs. Buck up for it.

Pick a newer transponder or go with older and tailbeacon.

Find a new or prior generation WAAS GPS navcom. You’ll have flexibility on wallet pain, depending on old or new, big screen or small.

If prior gen, figure out if you like the bigger or smaller form-factor - Garmin 430 or 530. If newer, look at both Avidyne 440 & 540, and Garmin 650 & 750. If you opt for a Garmin 430 or 530, the newer IFD 440 & 540 can used as an upgrade slide-in replacement with about 1hr labor (the hard part - tray & wiring - will already be done). With the 650 & 750, it’ll be more labor after the 430/530, unless you just start off with the 650/750. Get an indicator for VOR, LOC, GS.

Navcom2? Buy a handheld. Or keep one of your old radios if you must. Perhaps the coax or antenna or wiring just need to be “fixed”.

Math it. See if you can do owner-assist. It doesn’t have to cost $70k.
 
Since you asked...

To me the panel you described is a candidate for a fresh slate installation regardless of whether you intend to fly the airplane VFR or IFR. The positive to this route is that you're not throwing good money after bad, and there's almost nothing short of the TailBeacon that isn't a strong candidate for removal/replacement. That makes for a nice clean install avoiding the issues with, as you say, individual installations done by different installers. Also you'll avoid the incremental money vacuum which snakes out of the panel when you try to keep old equipment running.

I'd take a look at your budget and decide how much you could drop into panel. I tend to agree with the other advice given here, but in terms of bang for the buck it'd be hard to avoid strongly considering the GNC355 for your radio (GPS/COM) and a good audio panel. If you don't think you need an IFR GPS and want to get by with a VFR portable or something like that, you could save a little going with the GNC255 instead but for me the value proposition is the 355. That's screen real estate dedicated to something useful (the 355 screen) vs. the 255's basic display of frequency-related information.

The rest could come in stages. Only downside to doing an audio panel without the rest of the panel at the same time is you pay the shop to tear the panel back open every time they incrementally upgrade you and hook things up to that unit. But the budget will dictate what you can and can't do at a given time.

I'm looking to replace my remaining King KX-155 with a GNC355 at the end of the summer. Lots of owners are pulling these solid, reliable radios out for modern replacement, but they have a lot of life left. You could save some money buying a pre-owned KX-155 if this is a true shoelace budget proposition. You can't really go wrong with those, it's just that they're last-gen products.
 
That sounds very much like the panel I had to start out with. You may want to consider an upgraded panel like mine. It's barebones IFR, and very well equipped VFR. Perfect for the type of flying I do - good enough to get my rating and pop through a layer here or there, but not overloaded on cost, capability and need for currency.
https://www.pilotsofamerica.com/community/threads/panel-timeline.128700/
 
DenverDave said:
Haha yeah this wouldn’t be a good avionics thread without $70k of Garmin and $35k of Cessna.
Click to expand...
Let's put a price on a few options that were mentioned:

Option 1:
  • Audio panel (Garmin GMA345 or PS-Engineering PMA8000BT): $1500
  • GNX375: $8000
  • GNC255: $4000
  • COM2 (Trig TY96A or GTR225): $1800
  • CDI (MD200-706): $2000
  • Relays and switches to select the CDI between the GPS and the NAV: $500
Total: $17800 + 40-50 hours labor

Option 2:
  • Audio panel (Garmin GMA345 or PS-Engineering PMA8000BT): $1500
  • GNC355: $7000
  • GTX345: $5000
  • GNC255: $4000
  • CDI (MD200-706): $2000
  • Relays and switches to select the CDI between the GPS and the NAV: $500
Total: $20000 + 40-50 hours labor

Option 3:
  • Audio panel (Garmin GMA345 or PS-Engineering PMA8000BT): $1500
  • Used GNS430W: $4000
  • Used GTX330ES: $2000 (Does not have ADS-B/In)
  • COM2 (Trig TY96A or GTR225): $1800
  • Used CDI (GI-106): $1500
Total: $10800 + 40-50 hours labor
 
No mention of autopilot, or what the value of the plane is.

My recommendations for someone with a $100,000 plane would be different than someone with a $40000 plane.
 
Definitely start from scratch if you really want to fly this thing around, and especially if you want to fly IFR trips.

For VFR only:
  • Modern audio panel - (new from PS Engineering, or maybe a used one-model-back Garmin or PS) This will solve your radio interfacing and intercom issues.
  • WAAS GPS (with an eye to the future IR) - a GNX-375 gets you 1090ES ADS-B in and out, plus a modern GPS unit and screen. And only one GPS antenna. You can pretty much get into anywhere with LNAV/LPV approaches.
  • Modern NAV-COM - GNC 255 (provides ground-based NAV backup plus LOC/ILS capability)
  • CDI - Used GI-106 should be affordable and relatively easy to find with all the G5 upgrades going on. You will need a separate, properly annunciated CDI for IFR ops with the GPS. I suspect it is possible to make it switchable between GPS and NAV
Not cheap, but this would have you completely covered for VFR and IFR XC and training.

If you want more redundancy for IFR flying, I would consider adding a second COM (nothing fancy required - you will use this mostly for ATIS and Ground, or for emergency backup), an AP, and G5s in that order. When you add the G5s, your vacuum system can likely come out.

Personally, I would not go for a used GNS-430 at this point, as these units are far into their useful lives. It makes sense to keep them if you still have one, but if starting over, I would get something more modern--they have better screens, use non-proprietary memory cards, and have more capability. Even if you bought a GNS-430 now with the intention of swapping it for an IFD-440 later, it's not clear how much you would really save going that route.

Of course if this is not a keeper plane, doing avionics upgrades will be a significant financial sink. You will not recover these costs at resale. If this is a keeper plane, then you will appreciate the upgrades for many years. Until the next set of upgrades...
 
Older 172? VFR only? Ebay is your friend.
Used audio panel/intercom, used radio, keep the transponder and tail beacon you already have. If you want to splurge you can add a used non-waas 430.

That gives a vast improvement over where you are now for not a ton of cash and will probably provide everything the plane will need for VFR for at least the next 20 years. Yep its all used stuff that is no longer supported. Putting in new or used but still supported hardware will cost a lot more and won't add much more to resale value than this stuff would.
 
chemgeek said:
Definitely start from scratch if you really want to fly this thing around, and especially if you want to fly IFR trips.

For VFR only:
Click to expand...

VFR only - delete all the above stuff and just get a new com radio. That plus a stratux ADSB-In with FlyQ/Foreflight on an iPad/iPhone gets you all the Com and NAV that you need for only $2000. It won’t get you IFR, but the cost savings may be enough to pay for the rental time.

You can put in a GTR-200 for $1200 ( or GTR-225 if your IA won’t sign off on the -200). These have a built in 2 place intercom and can also monitor a second frequency so are nearly as good as two radios.

Clean out all the old crap and wiring and you will save a bunch of weight and when it is time to sell, the new buyer may even like that all the old wiring and obsolete equipment is already gone and ready for what they want to install.
 
DenverDave - With your handle, I assume you're in the Denver area. PM me, we'll talk. I'm going thru an upgrade now.
 
Juliet Hotel said:
Older 172? VFR only? Ebay is your friend.
Used audio panel/intercom, used radio, keep the transponder and tail beacon you already have. If you want to splurge you can add a used non-waas 430.

That gives a vast improvement over where you are now for not a ton of cash and will probably provide everything the plane will need for VFR for at least the next 20 years. Yep its all used stuff that is no longer supported. Putting in new or used but still supported hardware will cost a lot more and won't add much more to resale value than this stuff would.
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Problem is finding a shop that will do the installation without selling the OP the hardware. Labor and parts is one thing, but the sugar money is the profit off the hardware.
 
murphey said:
Problem is finding a shop that will do the installation without selling the OP the hardware. Labor and parts is one thing, but the sugar money is the profit off the hardware.
Click to expand...
If he goes bare bones VFR and only puts in a GTR-225 (takes the place of both intercom and radio 1+monitor2) he can do the work himself if his friendly AP/IA will sign it off after. It is cramped and not the nicest work to do well, but not really very hard when ripping things out and replacing from scratch.
 
Matthew Rogers said:
If he goes bare bones VFR and only puts in a GTR-225 (takes the place of both intercom and radio 1+monitor2) he can do the work himself if his friendly AP/IA will sign it off after. It is cramped and not the nicest work to do well, but not really very hard when ripping things out and replacing from scratch.
Click to expand...
Why do so many people around here assume everyone has the knowledge and expertise to install avionics? I was under the assumption that avionics had to be signed off with an FCC cert, not an FAA cert. Was I wrong?
 
murphey said:
Why do so many people around here assume everyone has the knowledge and expertise to install avionics? I was under the assumption that avionics had to be signed off with an FCC cert, not an FAA cert. Was I wrong?
Click to expand...
I don’t have any specific expertise and I installed a GTR-200 in a certified plane and had my AP/IA sign off on the install. So if I did it, why not the OP? If you can read a set of directions, you can install a radio. If you can’t read, then maybe you shouldn’t be flying.
Now if you just don’t want to do the work, sure, wait a few months and pay someone else to do it for you.
 
A&P/IA can sign off installs... no FCC cert required.
 
Mtns2Skies said:
That sounds very much like the panel I had to start out with. You may want to consider an upgraded panel like mine. It's barebones IFR, and very well equipped VFR. Perfect for the type of flying I do - good enough to get my rating and pop through a layer here or there, but not overloaded on cost, capability and need for currency.
https://www.pilotsofamerica.com/community/threads/panel-timeline.128700/
Click to expand...

Great thread! I'm not ready to spend major $$ on avionics yet due to my low requirements (com, intercom and transponder) and upcoming overhaul but if it turns into a keeper your panel is similar to where I'd take it eventually. How do you like the panel-mount Aera 660?

MooneyDriver78 said:
No mention of autopilot, or what the value of the plane is.

My recommendations for someone with a $100,000 plane would be different than someone with a $40000 plane.
Click to expand...

It's a 1971 172 that I paid $32,000 for and probably overpaid. It has about 15% of an ARC 300 autopilot that hasn't been complete since 1974.

Matthew Rogers said:
VFR only - delete all the above stuff and just get a new com radio. That plus a stratux ADSB-In with FlyQ/Foreflight on an iPad/iPhone gets you all the Com and NAV that you need for only $2000. It won’t get you IFR, but the cost savings may be enough to pay for the rental time.

You can put in a GTR-200 for $1200 ( or GTR-225 if your IA won’t sign off on the -200). These have a built in 2 place intercom and can also monitor a second frequency so are nearly as good as two radios.

Clean out all the old crap and wiring and you will save a bunch of weight and when it is time to sell, the new buyer may even like that all the old wiring and obsolete equipment is already gone and ready for what they want to install.
Click to expand...

I'm really leaning towards the GTR 225 for my only com. Already have a Stratus 3 and a bluetooth headset for audio alerts.

murphey said:
DenverDave - With your handle, I assume you're in the Denver area. PM me, we'll talk. I'm going thru an upgrade now.
Click to expand...

That's actually expired information, now located in Arizona.

Matthew Rogers said:
I don’t have any specific expertise and I installed a GTR-200 in a certified plane and had my AP/IA sign off on the install. So if I did it, why not the OP? If you can read a set of directions, you can install a radio. If you can’t read, then maybe you shouldn’t be flying.
Now if you just don’t want to do the work, sure, wait a few months and pay someone else to do it for you.
Click to expand...

It doesn't look that hard and there is a lot of documentation between the install manual and AC 41.13-1b and -2b. I've built and rebuilt a few automotive wiring harnesses among many other projects.

----

Thanks for the replies everyone. This thread has helped me realize I want equipment that will meet my immediate needs, not preclude future upgrades and be reliable for the foreseeable future.

I'm now pretty set on the GTR 225. If I take it IFR in a 3-5 years I'd be able to put it in the number 2 com spot and just add an audio panel and a GPS/nav/com pretty easily.

As far as transponders go, GTX 327 looks like a quantum leap forward compared to my rickety KT78, and they're very affordable. But it's also 20+ years old. It might be wise to sell the tailbeacon while it's worth something, buy a GTX 335 kit and use the GPS antenna to plug the upcoming ADF sense antenna hole. Something about the GAE 12 would would be compatible with how I feel towards "remote boxes."

I have a 4-place aircraft but the GTR 225 only has a 2 place intercom. I already have a 4-place intercom installed that may be able to be sorted out. I've never had someone in the back seat but 3 people on a short flight isn't out of the cards. Would a portable intercom be able to work with the GTR built-in intercom to give me more headphone jacks?
 
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DenverDave said:
I'm not an avionics tech but after giving my avionics a good visual inspection there are a lot of problems.

My panel is typical junk:
King KMA 20 TSO audio panel
(When listening to com 1 on phones you can faintly hear com 2)
Narco MK12D replacement for a field-installed RT308
(Nav INOP, glass on ARC IN-525A indicator loose, connector on KN-75 GS receiver broken/loose. Low range for com transmissions.)
TKM MX12 replacement for a field-installed MK12
(Nav INOP, low range for comm transmissions.)
ARC 300 ADF
(INOP)
King KT78 transponder, Tailbeacon ADSB
(Works)
SPA-400 Intercom
(Can't transmit with intercom off even though manual says you can)
Remote ARC marker beacon system in addition to the KMA 20
(Obviously INOP)

And not to mention the ungodly mess that a half dozen independent avionics installations have caused. Wire security is weak, stuff touches the yoke "Y" when at full travel and remote boxes are loosely stuffed in every spot imaginable.

I'm VFR-only although I'd like to be IR. IR is more of a pipe dream at this point.

If the nav stuff is dead forever I'd probably just prefer it wasn't on board. If I was paying for labor of removing all the useless nav junk and fixing the comm issues maybe I'd be better off pulling it all and installing something clean and simple like a GTR 225 and a GTX 327.
Click to expand...
Three pieces of advice on system design from a (non-aviation) technology architect:
  1. Decide what you want to be able to do and what capabilities you need to do it before you start looking at products.
  2. Build for today, not tomorrow — you'll be wrong about 50% of what you think you'll need "some day," so put in only what you're certain you'll need in the next 12 months.
  3. Notwithstanding #2, leave the door open for the "maybes" in the future (tell the avionics tech what you might be adding in a few years, and ask them what you can do now to make it easier then).
 
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DenverDave said:
How do you like the panel-mount Aera 660?...I'm now pretty set on the GTR 225.
Click to expand...
The aera 660 can send GPS coordinates to the GTR225 as well as tune frequencies. This is also true of the GTR200 and the Trig TY96A, except that the GTR225 requires a paid subscription to display the facility name. The ICOM A220TSO does not display facility names but can be tuned by the aera 660.

The GTR200 built-in intercom can do Bluetooth and 3D audio. The GTR225, TY96A and A220TSO cannot. The TY96A has playback capability while the others do not.

DenverDave said:
Would a portable intercom be able to work with the GTR built-in intercom to give me more headphone jacks?
Click to expand...
I've done it before. It wasn't ideal with wires running around and finding a place to put the box, but it was OK for occasional use.
 
Your spec cries out for a PAR200B, which gets you into a top-tier audio panel and intercom (and you won’t realize just how much that matters until you have a modern and good audio panel), and integrated comm.

https://www.ps-engineering.com/PAR200B.html

This gets you into both audio and new comm with dramatically reduced install burden (and cost).

Then, add either a used 430W, which gets you a second comm, NAV and GPS, or a Garmin GNX375, gets you an IFR-cert GPS and ADS-B out, in one box.
 
murphey said:
Why do so many people around here assume everyone has the knowledge and expertise to install avionics? I was under the assumption that avionics had to be signed off with an FCC cert, not an FAA cert. Was I wrong?
Click to expand...

Yep.

Jim
 
SCCutler said:
Your spec cries out for a PAR200B, which gets you into a top-tier audio panel and intercom (and you won’t realize just how much that matters until you have a modern and good audio panel), and integrated comm.

https://www.ps-engineering.com/PAR200B.html

This gets you into both audio and new comm with dramatically reduced install burden (and cost).

Then, add either a used 430W, which gets you a second comm, NAV and GPS, or a Garmin GNX375, gets you an IFR-cert GPS and ADS-B out, in one box.
Click to expand...

I was thinking the same thing. I love my PAR200B, having a modern audio panel is life altering. When I call someone, they can't tell that I'm in my airplane.
 
Thanks again for the replies everyone , I’ve done some more investigation and I’m now convinced my biggest issues are antenna and coax related. My com antennas have around 1 ohm resistance between the mounting screws and the aluminum they are mounted to. Actually one is worse than the other. My nav antenna coax center conductor does not have continuity along the main run from under the panel to the base of the vertical stabilizer. I would certainly need to resolve these issues if I were to install new avionics so I might as well fix them now and see how it works.
 
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