Cessna 182 Avionics upgrade

Supereri

Pre-takeoff checklist
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Supereri
I have a 182F. It's in the shop to get the Dynon autopilot installed as well as a GTN750. Currently it has:
Dynon Skyview 10" HDX
Dynon Comm
Dynon GPS (non-ifr)
Dynon ADSB in/out
Dynon Engine Monitor
Garmin GNC-355

I've purchased a GTN750 for the larger screen as well as the Nav radio. My original intent was to remove and sell the GNC355. to offset some of the GTN cost. But, now I'm wondering if I should just yank the Dynon Comm, leave the GNC, and add the GTN. Leaving my with 2 Garmin Comm radios, one nav radio, and 2 WAAS GPS in addition to the non-WAAS Dynon GPS.

Is there much benefit to the second WAAS gps?
 

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What is the failure rate of gps waas? Is there some other reason to need two? Obviously great to have though
 
I have a GTN 750 and the GNC 355 as backup and com2. As of a recent update they work great together! When I first got the 355 (already had the 750) they didn’t communicate at all. Now with the latest update they work together perfectly!
 
I have a GTN 750 and the GNC 355 as backup and com2. As of a recent update they work great together! When I first got the 355 (already had the 750) they didn’t communicate at all. Now with the latest update they work together perfectly!

What did the update enable? I’m considering a similar avionics upgrade and would be interested in how they play together.


Sent from my iPhone using Tapatalk
 
What did the update enable? I’m considering a similar avionics upgrade and would be interested in how they play together.


Sent from my iPhone using Tapatalk

Before the update they really didn't communicate at all. You had to program both, one by one and update both databases independently. Now with V 3.2 update on the GNC355 they do cross fill for flight plans and database sync between the two.
 
I have a 182F. It's in the shop to get the Dynon autopilot installed as well as a GTN750. Currently it has:
Dynon Skyview 10" HDX
Dynon Comm
Dynon GPS (non-ifr)
Dynon ADSB in/out
Dynon Engine Monitor

Very similar approach to what I am looking to get, when I get my 182. I will start my buying process in 4'ish months. For education, why are you sticking with Garmin for your GPS/Radio and not Avidyne? Also, is the Dynon GPS in you plane non-IFR due to a lack of Garmin integration or something else? The reason I ask is my planned panel is very similar but all Dynon and Avidyne and I want to see why others choose what they choose.
 
Very similar approach to what I am looking to get, when I get my 182. I will start my buying process in 4'ish months. For education, why are you sticking with Garmin for your GPS/Radio and not Avidyne? Also, is the Dynon GPS in you plane non-IFR due to a lack of Garmin integration or something else? The reason I ask is my planned panel is very similar but all Dynon and Avidyne and I want to see why others choose what they choose.

Maybe non-IFR was the wrong wording for me to use. My understanding of the Dynon GPS in the Skyview is that it's WAAS, but can't be used to fly an approach legally. But, I'm no expert and I would encourage you to doublecheck before you spend money based on my info. My airplane already had the 355 when I bought it and I stuck with Garmin for the 750. I bought it used for about the same as a used Avidyne and it has a warranty. Now that I'm considering keeping the 355 in addition to the 750 I'm glad I stayed Garmin. Honestly there wasn't a super compelling case for me to go Garmin or Avidyne when I researched.

Because of my work I could even have gotten a discount on a new Avidyne, but I never fully considered new it due to cost.
 
The integrated GPS for the HDX is not IFR certified. I can’t tell you if there is an actual performance difference from a WAAS IFR certified Avidyne or Garmin. I went with a IFD440 for the GPS/Comm/Nav and the Dynon integrated radio for my second comm.
 
I would keep the Garmin's and get rid of the non IFR Dynon GPS and the Dynon Com. That will leave you with 2 Garmin GPS's, 2 Coms, and 1 Nav radio.

Yak - are you saying the new Dynon HDX that he is putting in can't be used for IFR??? Is it because it can't talk to the GTN 750?
 
I would keep the Garmin's and get rid of the non IFR Dynon GPS and the Dynon Com. That will leave you with 2 Garmin GPS's, 2 Coms, and 1 Nav radio.

Yak - are you saying the new Dynon HDX that he is putting in can't be used for IFR??? Is it because it can't talk to the GTN 750?
He's saying the HDX alone is not an IFR navigator despite having a gps. The GTN will talk to Dynon. The engine monitor, transponder, adsb, com radio, autopilot all run through the Dynon hdx which has its own internal gps.

The dynon hdx gps is the on par with the G3x...also not an approved IFR navigator. Losing the Dynon gps means losing all of his primary instruments. Was a bit redundant to say Dynon gps as it is in the hdx itself.

I would leave the 355. If the magic smoke leaves the 750 you've got the 355. You've already own it. And it's not my money, but why sell it and have something not as capable ie Dynon com....unless you have a 3 com capable audio panel, then id keep everything.

Edit: I see the Ps engineering audio panel. Love mine. But since you're putting in the GTN 750, why not put in the gma35 and run the audio panel through the GTN. Then you'd be 3 com capable and save a little space by removing the ps audio panel

Again....not my money
 
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Very similar approach to what I am looking to get, when I get my 182. I will start my buying process in 4'ish months. For education, why are you sticking with Garmin for your GPS/Radio and not Avidyne? Also, is the Dynon GPS in you plane non-IFR due to a lack of Garmin integration or something else? The reason I ask is my planned panel is very similar but all Dynon and Avidyne and I want to see why others choose what they choose.
GTN 750 has a diagonal screen size 1.2" larger than the ifd540.

I think we all would want an extra 1.2"
 
He's saying the HDX alone is not an IFR navigator despite having a gps. The GTN will talk to Dynon.

Makes sense - thanks!

I would leave the 355. If the magic smoke leaves the 750 you've got the 355.
....... But since you're putting in the GTN 750, why not put in the gma35 and run the audio panel through the GTN. Then you'd be 3 com capable and save a little space by removing the ps audio panel

The audio panel through the GTN is slick, but I like your earlier point that you could loose the GTN, which in this case you'd loose radio control. Thus, I'd vote for keeping the existing audio panel. (Appreciate being invited to offer opinions on how to spend other people's money :) )
 
(Appreciate being invited to offer opinions on how to spend other people's money :) )

Its one of my favorite things to do, and didnt see anyone else suggest using the gtn as the audio panel
 
You will lose the interface from the Com radio to the Dynon screen, plus the airport tuning, if you remove the Dynon COM. You cannot remove the Dynon GPS, as it's part of the system and is required by the STC. If you keep the 355 and add the GTN, you will need a second ARINC Adapter. I would certainly keep the Dynon COM if it were my plane. I love the features.
 
You will lose the interface from the Com radio to the Dynon screen, plus the airport tuning, if you remove the Dynon COM. You cannot remove the Dynon GPS, as it's part of the system and is required by the STC. If you keep the 355 and add the GTN, you will need a second ARINC Adapter. I would certainly keep the Dynon COM if it were my plane. I love the features.
Yes, I agree about the Dynon COM. I think I'm going to go with GTN COM1 and GNC COM2 and get rid of the Dynon COM. Otherwise I think I would have to purchase a new vertical Dynon COM due to layout, which isn't the end of the world, but I would end up with 3 COM radios and only 2 COM on my audio panel. I could just not hook one up I suppose (GNC would be the one not to be used). If I don't keep the Dynon Com I think/hope I'll get used to the buttonology of the GTN/GNC.

Never any thought about dumping the Dynon GPS. Besides it being required it's great for VFR flight. I'm sure I'll actually end up using it more than the GTN or GNC in the long run.

Does the ARINC module have 2 channels and would the GTN and GNC each use one? If I need another ARINC I might need a second hub, I will have to check with my installer.
 
Sell the GNC and install a GPS175. You'd be money ahead and still have the same functionality. I think the GPS side connecter wouldn't need to change. You can buy just the vertical Dynon COM Panel for $425 and sell your horizontal for at least half that, probably.

The ARINC has 2 channels. The GNC/GPS175 uses 1. The GTN would use 2, one for GPS and one for VLOC. You could just use the GPS175 RS232, but you would get no glide slope from it. The extra ARINC Adapter costs $475.

As for the extra hub, you could just get a network splitter instead of a hub if you don't have enough open ports now.
 
Maybe it was mentioned earlier, but my PMA6000b has a slide in replacement PMA7000M-BT. This gives me 3 COM inputs and bluetooth built in. Install is simply a screw slide the old one out and slide the new one in. Obviously the COM3 would need to be wired as well, but seems pretty low effort.

I wish I lived closer to your shop Jesse. Your help and advice are wonderful and you are obviously a true expert when it comes to this stuff. Hopefully more folks see your input and effort on this forum and seek out your shop for work.
 
I'd feel most comfortable with two independent approach-capable navigation sources.
Both the GNC355 and the GTN750 are capable of approaches...

I know you're talking ground-based nav, but I've been thinking about my next upgrade for a while, and I don't think I'm going to bother with two Nav radios any more. Since I got my 750, I don't know that I've shot a single non-RNAV approach with it outside of testing/proficiency. When it's the real deal, I'll take an RNAV LPV every time.

Now, starting from there - If either of the boxes lets out its magic smoke, the other one can still shoot an RNAV LPV approach, and RNAV approaches in general are far more available than ILS approaches. If somehow the GPS system goes down or gets jammed or otherwise unreliable, I still have a box that can shoot an ILS.

With the ground based navaids going away at the rate they are, IMO you're much better off with your #2 being a GPS/Com than being a Nav/Com, if you're not going to spring for a second Nav/Com/GPS. I mean, when was the last time you saw dual ADF?

So, at our next upgrade, I think it's likely that we'll pull the current #2 KX-165 and put in a GNC 355. The GTN 650 is just overkill to have a second Nav radio when I hardly even use the first one any more.
 
So do you get the transponder/GPS and a second com radio, or a GPS/Com and a separate transponder?
 
Both the GNC355 and the GTN750 are capable of approaches...

I know you're talking ground-based nav, but I've been thinking about my next upgrade for a while, and I don't think I'm going to bother with two Nav radios any more. Since I got my 750, I don't know that I've shot a single non-RNAV approach with it outside of testing/proficiency. When it's the real deal, I'll take an RNAV LPV every time.

Now, starting from there - If either of the boxes lets out its magic smoke, the other one can still shoot an RNAV LPV approach, and RNAV approaches in general are far more available than ILS approaches. If somehow the GPS system goes down or gets jammed or otherwise unreliable, I still have a box that can shoot an ILS.

With the ground based navaids going away at the rate they are, IMO you're much better off with your #2 being a GPS/Com than being a Nav/Com, if you're not going to spring for a second Nav/Com/GPS. I mean, when was the last time you saw dual ADF?

So, at our next upgrade, I think it's likely that we'll pull the current #2 KX-165 and put in a GNC 355. The GTN 650 is just overkill to have a second Nav radio when I hardly even use the first one any more.
This was my approach when my old nav / com 2 (kx170b) started flaking out and eventually died. I decided to go with a GNC355 as a com 2 and backup nav to my GTN750. There are way more GPS approaches then ground based nav approaches. It's also nice to have 2 screens, I mostly keep the GNC355 on the traffic screen when in route. The price difference between the GNC355 (Com radio and GPS) vs the GNC255 (nav/com radio) was only $1,200 when I had it done.
 
When I do my upgrade, I will end up with both a 750Xi and 650Xi. But mainly due to already having the 650Xi. And the delta between keeping it and putting in something like a 355 was not enough to go that way.
 
Both the GNC355 and the GTN750 are capable of approaches...

I know you're talking ground-based nav, but I've been thinking about my next upgrade for a while, and I don't think I'm going to bother with two Nav radios any more. Since I got my 750, I don't know that I've shot a single non-RNAV approach with it outside of testing/proficiency. When it's the real deal, I'll take an RNAV LPV every time.

Now, starting from there - If either of the boxes lets out its magic smoke, the other one can still shoot an RNAV LPV approach, and RNAV approaches in general are far more available than ILS approaches. If somehow the GPS system goes down or gets jammed or otherwise unreliable, I still have a box that can shoot an ILS.

With the ground based navaids going away at the rate they are, IMO you're much better off with your #2 being a GPS/Com than being a Nav/Com, if you're not going to spring for a second Nav/Com/GPS. I mean, when was the last time you saw dual ADF?

So, at our next upgrade, I think it's likely that we'll pull the current #2 KX-165 and put in a GNC 355. The GTN 650 is just overkill to have a second Nav radio when I hardly even use the first one any more.

OP was asking if they should remove the 355. That would leave them with only the 750. I agree that GPS/NAV+GPS seems perfectly sufficient.

FWIW I went with a GNC255+GTN650. I may regret not getting the 355 instead, but at least this way when the Garmin intern bricks my 650 I'll (in theory) have something running a different software stack.
 
You might want to consider our PAR200B, it is a hi-fi stereo, Bluetooth(R) enable audio panel that controls a remote-mounted TRIG TY-91L. Here's the link to the web page
PAR200B
 
OP was asking if they should remove the 355. That would leave them with only the 750. I agree that GPS/NAV+GPS seems perfectly sufficient.

FWIW I went with a GNC255+GTN650. I may regret not getting the 355 instead, but at least this way when the Garmin intern bricks my 650 I'll (in theory) have something running a different software stack.
So here's the current plan.

Retain Dynon Comm radio (COM1). The integration with the HDX10 is just too handy to give up
Install GTN750 (COM2)
Retain GNC355 (COM not connected) I could sell, but a GPS 175 is roughly the same cost as I would get out of my 355. We'll look at wiring the 355 COM into where it would go if I got the PMA7000M-BT as COM3. This will make the upgraded audio panel a 1 hex nut and log entry install if it works out.
Entirely new panel is being cut including the lower stock Cessna portions. powder coat existing glovebox to match panel
Dynon Autopilot is currently finishing installation
Move existing audio jacks from below main panel to on the main panel
Laser etch placards and labels into powdercoat on new panel
Moving the rear audio jacks. They are mounted vertically in the floor under the rear seat. I want to move them to the side wall but that's more $$ and time. This one is still under consideration

Things I'm likely not doing:
Buying a new audio panel. $$ are not unlimited and I just don't see 3 COM radios, plus a handheld, as being worth the extra $1700
Add a second Stratus USB charger on the left panel
New glareshield/eyebrow
New carpet, mine is really bad and I considered just purchasing new carpet while it's out. I'm going to try cleaning the existing to save $$
 
Well, we're finally nearing the end of this upgrade, hopefully. One change that was made. The GNC355 was replaced by a new GPS175. So I lost a comm radio, which I didn't have an input for on my audio panel anyway. I still have 2 comms, GTN750 and Dynon comm. This was a net positive $$ change for me and paid for a good portion of the new panel that was cut, powder coated, and laser etched.

The panel is going through the final integration. Hopefully it will be done this week. Here are the progress shots.
 

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BTW, definitely don't make the mistake of adding up all of the costs.
For anyone curious.
Used GTN750 (with warranty from Sarasota avionics), Dynon Autopilot, new panel, trade GNC355 for GPS175( credit applied to panel), associated hardware (gps antennae, arinc module, wiring, connectors, etc), new vertical Dynon comm/Knob panel)

My mechanic is doing the work flat rate. 40 hours autopilot install, 40 hours GTN install, and another 16 hours to switch out the full panel.
In addition he's done a TON of extra work to fix sins of the past. Rewiring audio panel, moving the rear headset jacks from the floor to the sidewall, replacing circuit breakers with push/pull breakers, fixed lighting wiring, installing new maplights, and a bunch of other items

All in it's going to be right around $32k. It's amazing how quickly it adds up.
 
Looks great.

Couldn't use a placard font a little bigger?

I would have dumped the old cessna switches for something else and made sure there was room for extra ones.
 
Looks great.

Couldn't use a placard font a little bigger?

I would have dumped the old cessna switches for something else and made sure there was room for extra ones.
I'm sure we could have used a larger font, but I'm pretty happy with the font size in person.

While this was happening the interior was out. I started to go down the path of replacing interior parts as well. But the costs and time away from the airplane kept adding up. I could have kept replacing things, but at some point I just had to say enough is enough.

There are a few extra circuit breaker holes already, which I think are the most likely additions. Honestly short of adding a second screen for the right side or replacing the audio panel I don't see much more that I'm interested in adding. This is everything I want.
 
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I'm sure we could have used a larger font, but I'm pretty happy with the font size in person.

While this was happening the interior was out. I started to go down the path of replacing interior parts as well. But the costs and time away from the airplane kept adding up. I could have kept replacing things, but at some point I just had to say enough is enough.

There are a few extra circuit breaker holes already, which I think are the most likely additions. Honestly short of adding a second screen for the right side or replacing the audio panel I don't see much more that I'm interested in adding. This is everything I want.
Gotta draw the line somewhere. I cheaped out on 1/2 the breakers. I left the primary bus alone with those crappy Cessna flush ones and put all the avionics on new Klixon breakers.
 
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