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G3x vs HDX vs status quo

traumamed

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I figured it only made sense to show off my ignorance on my very first post, so here goes.

I am buying an RV-6 with kind of an interesting panel. The installed equipment is a Dynon FlightDeck D180, Garmin G5, Garmin 430 (non-WAAS), Garmin GNX 375 (with WAAS and acts as the ADS-B in/out), panel-mounted Garmin Aera 796, Dynon 2-axis autopilot with both the AP74 and HS34 modules, an ARINC 429, and ICOM KA200 comms.

Fair warning, I haven't taken possession of the plane yet so some of this is conjecture. From what I can tell, it seems the 430 feeds to the D180 via the HS34/ARINC connection, while the G5 links with the GNX 375. The 375 is apparently not compatible with the D180. I'm not sure if the 430 talks to the G5. The 796 can pull data from either of the GPS navs but essentially just provides graphical services on a better screen than the 375 or 430.

I would like to upgrade from the D180 to either an HDX or a G3X, but I don't know which would be the most efficient route to go. On the one hand, almost the entire panel is Garmin except for the D180, so a G3X would probably play nice with everything already there. On the other hand, with the AP being Dynon, I would have to replace the servos if I went G3X, and I might have to redo the EMS stuff as well.

If I bit the bullet and went all Garmin, then both the G3X and existing G5 could theoretically drive the AP, correct? I think in an HDX setup keeping the Dynon servos, my G5 would remain orphaned from the AP, right?

All that said, the current setup isn't too shabby as is, and if I cannot do the upgrade for under $10K, I am not sure it's worth it at this point. The 796 fills in at least some of the "display" gap to provide a lot of the graphical information the D180 lacks vs the newer units. I am a long way from my IFR rating, so some of the added functionality of the upgrade might be of limited use for awhile.

If I'm analyzing this correctly, which maybe I'm not, it seems like the big gains would be: 1) IFR WAAS GPS from the 375X to the PFD instead of non-WAAS from the 430; 2) gaining a built-in VFR WAAS GPS; and 3) increased capabilities with the AP. What am I missing? Opinions/recommendations?
 
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You are asking the legendary “Chevy or Ford” question.

The autopilot servos you know have are a match to the SkyView system. You can have the G5 get a GPS feed from whatever you want.

The GNX 375 is a very expensive approach to ADS-B, and would not be the way to go for a new panel. But since you have it, replace the HS34 with the SkyView ARINC and it will play nice with the SkyView. What I don’t know is if it’s ADS-B out will be displayed on the SkyView moving map. For me, this is a must have. I just completed a southeast long cross country flight and the SkyView moving map, ADS-B weather and traffic on this integrate displayed provided the information for me to avoid multiple thunderstorms in a safe, and predictable fashion.

The SkyView EMS will be plug and play with you existing engine probes and such.

Carl
 
I am a long way from my IFR rating, so some of the added functionality of the upgrade might be of limited use for awhile.
?

I would recommend you do nothing for now. Work on the rating. By the time you have it you’ll be in a much better position to decide what you want/need.
 
Just me

Since you have a gnx375 you have the most expensive part. I would put a G3x systemin by adding a Gdu460 and the necessary support boxes. This in order to make full use of the gnx375
 
Since you have a gnx375 you have the most expensive part. I would put a G3x systemin by adding a Gdu460 and the necessary support boxes. This in order to make full use of the gnx375

This is what had me thinking the G3X might be worth at least considering, despite the prospect of needing to convert the autopilot and engine monitoring. It would be a bigger and more expensive project, but the final product would be fully redundant yet also completely integrated.

Carl, I see your point about the HDX route being the more straightforward plug and play route, which is what makes it so tempting - agreeing with the caveat that I would have to verify it can display the ADS-B data from the 375. It would be a no-brainer except I do not believe the Dynon AP could ever be driven by the G5. Might be worth the tradeoff though to keep the changeover simple(r).

Thanks for the input all, and Bob, your point is well taken.
 
If I bit the bullet and went all Garmin, then both the G3X and existing G5 could theoretically drive the AP, correct? I think in an HDX setup keeping the Dynon servos, my G5 would remain orphaned from the AP, right?

This is correct. To use the G5 in full backup mode including using the autopilot to fly instruments approaches when the PFD is unavailable, you would need to have the G5 installed with a Garmin G3X Touch system including autopilot servos.

If I'm analyzing this correctly, which maybe I'm not, it seems like the big gains would be: 1) IFR WAAS GPS from the 375X to the PFD instead of non-WAAS from the 430; 2) gaining a built-in VFR WAAS GPS; and 3) increased capabilities with the AP. What am I missing?

This is also correct.

If your G5 is already fully integrated with the GNX 375 and able to display the glidepath guidance on LPV approaches, then you already have a GAD 29 ARINC interface.

You should be able to re-use most of your existing engine sensors with the GEA 24 engine interface.

This diagram illustrates the necessary modules to take full advantage of your very capable GNX 375. If you want to continue to use your GNS 430, it can also be interfaced to the single GAD 29. This would give the system autopilot coupled VOR/ILS capability.

G3XTouch_GDU460withGNX375_GFC500.jpg

Steve
 
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This diagram illustrates the necessary modules to take full advantage of your very capable GNX 375. If you want to continue to use your GNS 430, it can also be interfaced to the single GAD 29. This would give the system autopilot coupled VOR/ILS capability.

Thanks for the diagram, it is very helpful. Unfortunately, it shows I will need even more Garmin equipment than I anticipated to make a change to a G3X. Probably around 10-12 AMUs in parts and then I'm guessing (total guess) 20-30 hours shop time for install, because that's not a job I dare tackle myself. Lots to think about. The argument to leave the system alone for now is looking more compelling, or maybe replace the D180 with a 7" HDX since that would be a much simpler and less expensive changeover but still provide a strong incremental upgrade.

Truthfully, RV10pilot and Bob are right on that the panel is good as is for the time being and I should really get into IFR training before I commit to something. The D180 is just old tech, and does not let me take full advantage of the GNX 375's capabilities. Of course I say that and plenty of folks are flying around just fine on steam gauges. Maybe I'm just trying to rationalize a decision to buy a new toy. :D
 
D180 vs HDX 7 inch

Regarding the D180, even though it is old it is still very good. I looked at HDX 7 inch for my new panel and that screen is just too small to easily view all of the information that is packed in. It would require a 10 inch display, or maybe two 7 inch displays.
A new Skyview installation in your case will also require ADAHRS and EMS modules, GPS source, wiring harnesses, bracket to remote mount the ADAHRS, extensions to pitot & static lines etc. so it's not actually a simple or inexpensive change over.
As others have said, I also suggest to just start flying the plane and then decide later on what if anything needs changing.
 
Regarding the D180, even though it is old it is still very good. I looked at HDX 7 inch for my new panel and that screen is just too small to easily view all of the information that is packed in. It would require a 10 inch display, or maybe two 7 inch displays.
A new Skyview installation in your case will also require ADAHRS and EMS modules, GPS source, wiring harnesses, bracket to remote mount the ADAHRS, extensions to pitot & static lines etc. so it's not actually a simple or inexpensive change over.
As others have said, I also suggest to just start flying the plane and then decide later on what if anything needs changing.

Great info, thanks. I have not seen an HDX in person, so hearing that the 7" is on the small side is good to know. I will have to try to get a look at one in person, or to scale at least. The way my panel is configured, I do not have the space to put in a 10" screen without significant "remodeling."

As far as the accessory units, I already have two GPS sources (see my equipment list in my first post) and an existing Dynon EMS that will confer some degree of compatibility, but I see your point that it isn't just plug and play.

Based on the feedback so far, I am leaning toward deferring a panel upgrade until a later date. I have some good equipment already installed that can be integrated into a future setup, but I may be best to hold off and just redesign the whole panel layout at some point down the line rather than throw a fair amount of money at a suboptimal solution. Thank you all for taking the time to offer suggestions.
 
Many of us are in the same situation, in my case a D100 and D120 with HS34, TruTrak autopilot, SL30, GNX375, and Aera 760. All works fine together.

I spent some time at Osh this year looking at upgrade alternatives and in each case the end result was a fair amount of panel rework, wiring rework, and lots of $$$ ($10k+) for somewhat incremental capability enhancement.

I decided to stick with what I have for now (also working on instrument rating) and agree with the suggestions to fly what you have for a while and then decide what you want/need.
Figs
 
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