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E-LSA GNX 375 Potential

MechaSteve

Active Member
I have some friends that are finishing a EAB RV-12, and they will be installing a Garmin GNX 375 as a GPS-only navigator (LPV / LNAV / VNAV only).

I know the E-LSA is limited to avionics kits through the manufacturer.

What would be the options for building an E-LSA with a GNX 375?

Would it be limited to petitioning VANS to add an option for the 375?

Would it be relatively feasible to build E-LSA with minimal G3X avionics, and add on later?


The GNX 375 is potentially a much cheaper/simple solution for navigation + ADS-B out/in.
 
You are pretty much correct.

The only way to do it would be for vans to develop an installation kit for what you want which is unlikely because it requires doing all of the work involved with developing full documentation, etc. that would support the installation.

Or build the airplane as a basic G3X system and then add the additional equipment after aircraft certification.
 
Would it be relatively feasible to build E-LSA with minimal G3X avionics, and add on later?
The GNX 375 is potentially a much cheaper/simple solution for navigation + ADS-B out/in.

I think that would be the way to go. The only item that you'd have to re-sell after you get the E-LSA AW cert. would be the transponder. You'd have to do some minor re-wiring to connect the GNX 375. I don't think its insurmountable, but its extra work.

I don't think the factory is interested in offering yet another avionics option.. however, there would be a decent price difference between the current IFR option, which is basically: G3X + GTN650xi + GMA245 + GTX35R vs. potentially new option: G3X + GTR200 + GNX375 (you lose VOR/ILS.. but as a bonus, you get UAT-in
(whereas you need the GDL50R if you wanted UAT-in)

Only way I could see the factory offering another option is if flight schools said "hey, just give us GPS if it means it'll be $5000 cheaper .. we're going to stop teaching VOR because its going the way of LORAN and NDB eventually anyway)
 
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EAB or Build E-LSA and add it later are the only two options I see since Vans probably won’t approve the deviation from the KAI.
 
EAB or Build E-LSA and add it later are the only two options I see since Vans probably won’t approve the deviation from the KAI.
That all makes sense, and it sounds like it is about what I thought.

I think my question at this point is "what is the most economical way to go about this?"

Is there a document that gives the exact contents of the standard dual G3X avionics kit?
 
I have some friends that are finishing a EAB RV-12, and they will be installing a Garmin GNX 375 as a GPS-only navigator (LPV / LNAV / VNAV only).

The GNX 375 is potentially a much cheaper/simple solution for navigation + ADS-B out/in.

The GPS175 is an even lower cost option. I'm adding the GPS175 in about two weeks (the unit ships 2/3/2023). The 375 adds another COMM, which would be very welcome, but would then require an audio panel and panel space is already taken up.
 
The 375 adds another COMM

The GNC 355 is the Navigator / Comm unit.

The ADS-B out transponder has a significant cost associated with it. Most of the "cheap" solutions assume the transmitter is being installed in an airplane with an existing mode S transponder.

The other option would be either the GTX 335R with built-in WAAS and the GDL 50R, or the GTX 435R w/WAAS.

I would *think* that the smaller number of devices and wiring would result in a lower price.
 
The avionics kit order form is undergoing upgrades right now.
Who knows, maybe they will add more "cost optimized" options?
 
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