Avionics Stack Order

SoCal 182 Driver

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SoCal 182 Driver
Friends - The avionics components in my Cessna 182 are (top to bottom): Audio panel, Avidyne IFD 540, KX155, Garmin 330ES transponder, DME, and autopilot. The problem I have is that I like to sit relatively high, and by doing so I have to duck down to see the audio panel (top of the stack) underneath the glare shield eyebrow. I'm getting a new autopilot installed, and I'm thinking of shuffling the avionics stack, as follows:

DME (top of the stack, rarely used, and I don't care if I occasionally have to duck down to see it)
IFD540
Audio panel (to me it makes sense to have the audio panel between the two radios)
KX155
Transponder
Autopilot

I'd appreciate thoughts and comments.

Thanks!
 
I'm an audio panel up top kind of guy. That's just me. But I can see all my buttons in my plane and don't have to duck down. Not sure how I'd feel about that. A lot of people are now putting the GFC500 up top but I think I'm leaving my audio panel up there and putting the GFC500 under my 530W.
 
I kind of like:
  • DME
  • Audio panel
  • IFD540
  • KX155
  • Transponder
  • Autopilot
Like @NealRomeoGolf , I prefer the audio panel up high.
 
How long have you had it set up this way?

In a critical situation, will you be able to “button push” correctly?

Right now, if you were in your pilot seat and closed your eyes, would you be able to touch the right knobs and buttons?

These are primacy questions. They may or may not make a difference in your situation, but only you can determine that.

Might be easier and safer if you kept the order the same, and moved the DME up top as you suggested. And I might be wrong.
 
I kind of like:
  • DME
  • Audio panel
  • IFD540
  • KX155
  • Transponder
  • Autopilot
Like @NealRomeoGolf , I prefer the audio panel up high.

This is my close second choice. Debating whether to have the IFD540 under the DME so it's as close to the top as possible, and more in my eye line.
 
This is my close second choice. Debating whether to have the IFD540 under the DME so it's as close to the top as possible, and more in my eye line.
Up in your eye line is good. A farther distance for your hand to move to the GPS buttons/knobs not so good.
 
Up in your eye line is good. A farther distance for your hand to move to the GPS buttons/knobs not so good.

I think the distance difference in my hand going from the yoke to the GPS would be nominal in either location.
 
I kind of like:
  • DME
  • Audio panel
  • IFD540
  • KX155
  • Transponder
  • Autopilot
Like @NealRomeoGolf , I prefer the audio panel up high.

How often and when do you use:
Transponder…maybe twice a flight?
KX155…maybe use for ATIS, monitor guard, etc?
DME…once on approach, otherwise like most you’ll be using GPS.

So I would put the above in the right stack.
 
DON'T. Unless you're doing the installation yourself and really, really like tinkering, don't move instruments around. It gets expensive really fast and doesn't buy you anything.
 
Opinion: If, and I mean IF(!), there is enough slack in the wires to move the complete stack (except the DME) down a hole or two, have your avionics guy remove the DME and it's antenna , then, let him see how much he can slide the rack down without rewiring. If you can get 2 holes lower that should help. Even 1 hole might be all you need. The minute you start rewiring, the $$ grow quickly.
 
DON'T. Unless you're doing the installation yourself and really, really like tinkering, don't move instruments around. It gets expensive really fast and doesn't buy you anything.

The panel is going to be torn apart for dual G5 and autopilot installation. If I’m going to make any changes, that would be the time.
 
Opinion: If, and I mean IF(!), there is enough slack in the wires to move the complete stack (except the DME) down a hole or two, have your avionics guy remove the DME and it's antenna , then, let him see how much he can slide the rack down without rewiring. If you can get 2 holes lower that should help. Even 1 hole might be all you need. The minute you start rewiring, the $$ grow quickly.

I would think the DME’s wiring and cabling would be pretty simple to revise, if necessary. I guess some of the decision-making will be dictated by what we find in terms of cable and wire slack.
 
Do you find the DME all that useful? I would trim the weight out of the plane as long as the panel is opened up. I would keep the audio panel at the top, because it is the one you look at the least and you can probably find the button you need to change radios without looking. But if that's bothering you already then your opinion should prevail over mine.

The main thing is going to be where the IFD is easiest for you to use, since it's the one you interact with the most. Everything else can be decided based on that.
 
I just dropped my 182 off at the avionics shop this morning to finally drag it out of the 1980s. We're replacing everything. I also thought about keeping the DME (this is the first plane I've flown that had one and I thought it was neat), but was very easily talked out of it. Extra weight, heat, and power draw...didn't seem worth it.

I decided on this for the stack:
Audio panel
GTN750
GFC600
#2 Nav/Com
Transponder

I also think the spot right under the glare shield is kind of an annoying place, so kept the audio panel there to give the 750 some breathing room. Then everything under that in the order of more frequently touched to least. And when I use the a/p my hand won't block my view of the navigator. That's probably not too big a deal, but IDK, maybe a slight benefit.
 
I just dropped my 182 off at the avionics shop this morning to finally drag it out of the 1980s. We're replacing everything. I also thought about keeping the DME (this is the first plane I've flown that had one and I thought it was neat), but was very easily talked out of it. Extra weight, heat, and power draw...didn't seem worth it.

I decided on this for the stack:
Audio panel
GTN750
GFC600
#2 Nav/Com
Transponder

I also think the spot right under the glare shield is kind of an annoying place, so kept the audio panel there to give the 750 some breathing room. Then everything under that in the order of more frequently touched to least. And when I use the a/p my hand won't block my view of the navigator. That's probably not too big a deal, but IDK, maybe a slight benefit.
Any particular reason you chose the GFC 600 over the GFC 500? Are you putting in an EFIS, like a G5 or GI 275? If I had a choice, I would choose between a G3X Touch + G5, G3X Touch + GI 275, and dual GI 275 to run alongside a GTN 750 Xi and GFC 500. I like the knobs on the GFC 500 better than the screen on the GFC 600. :)
 
Yes, I'm putting in a G500TXi, and a GI 275 standby. My avionics guy gave me the G3X + G5 option too and he was pretty open that he thought I'd be really happy with either one. I also considered a couple of GI 275s only, and that was the plan for a while until I realized I'm spending so much money on the rest of the upgrade that going up to a full screen PFD made more sense. So I stretched the budget and went with the G500 for a couple reasons but the biggest one was I just wanted to put the newest stuff available into the plane and then hopefully leave it alone for a long time. Buy once, cry once kind of thing.

I like the knobs on the GFC 500 better than the screen on the GFC 600.

I actually do too, it was one of the negatives of going with the 600. I was talking with my installer and trying to understand various failover scenarios, and what I got was the GFC 500 only interfaced with the GI 275 and if that instrument failed it would also take the autopilot with it. I asked why it couldn't fail over to the G500 and he said he thought that was a marketing decision by big G. Who knows. But then he mentioned that the 600 had it's own integrated AHRS, and that just seemed better to me. But I do realize, I only traded an external AHRS for an internal one. Is that setup that much more reliable? IDK, maybe that was more of an emotional decision. But it meant that I would have three AHRS units in the plane and that combined with the heavier servos, and his opinion that it was maybe a little smoother, and I fell into the "for only a couple thousand more..." trap.
 
Sounds fair to me. In my RV-14, the GMC 507 had an update last year that allowed its internal AHRS to be cross-checked against the rest of the G3X system. With it active, I got constant G3X alerts for pitch and roll trim faults even on the ground. Garmin eventually told me that the AHRS was mostly intended for certified G3X installs, which doesn't make me feel better about my plane or certified installs, but I turned it off and haven't had a problem since. I already have three AHRS units: two for the G3X plus the G5, which at least in experimental land can be used as a reference to show on the G3X Touch display if there are no working G3X AHRS inputs.

If you're going with the TXi, then the GFC 600 does seem more sensible. I also considered a dual GI 275 to support a new autopilot and suffered from scope creep. In the end, primary EIS was just too much of an upgrade to pass up.
 
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