Glass panel / Garmin newbie question

Just starting my fuselage so I probably shouldn?t be even thinking about avionics, but here I am sitting here thinking about avionics. After doing some searching, I?m left pretty confused about the design of a glass panel system, particularly about how you know what components you need given your airplane?s mission. There are so many components and options, and many products? capabilities seem to overlap.

Let?s say I?m intending to go VFR only and I want a GPS. And we?ll pick a vendor: Garmin. So these guys have their G3X touch displays (GDU 450/460/470) which have VFR WAAS GPS. Great! But wait.. they also offer a GPS 20A box also with VFR WAAS GPS. I guess it?s different because it can be used with ADS-B out. So would I need both for ADS-B position out? But then wait?they also have this GTN 625 which also looks like a GPS display but it?s massively more expensive than the GDU. What am I getting that I don?t with the GDU displays?

And this is just one product (GPS display) out of one product line (G3X) from one vendor (Garmin). How do you guys start out navigating all this information? Is there a beginner?s guide somewhere? Any advice?

VFR Only, the built in GPS's built into the G3X GDU's work great.

If you add ADS-B out, you will need a certified position source. There are several ways to skin that cat but the GPS 20A is one way to complete the mission. It can run in parallel to the G3X built in units.

If you ever want to fly IFR and need a TSO'd IFR Navigator, then the GTN series fills that need. You are paying for the TSO'd nature of the box. Not needed for VFR. The GTN can also provide a certified position source for ADS-B out so in a sense it can kill 2 birds with one stone. However, this option is not cost effective for a VFR only airplane.

My airplane has 8 GPS's in it at any given moment:

1 in the Garmin G5 backup PFD
1 in the main PFD
1 in the MFD
1 in the GTN
1 in the GDL39 3D
1 in the APRS transmitter setup
1 in the iPAD
1 in my iPhone

The bottom line is that as you have found, the options can be overwhelming.

This diagram has a ton of info embedded:

Chapter 1 of the G3X installation manual (the G3X touch manuals are found here) is a great place to start. Similarly, you can get the installation manuals for other manufacturers, which should let you know what optional equipment you will need. The nightmare only begins when you mix and match manufacturers...

Steinair

My and your best path to go is to contact Steinair and ask then whaf is best. I BOUGHT the garmin pkg thru Vans. Steinair supplied the pkg and wire harness and were great to work with. CALL THEM!

Hi Ryan,

I'm based at LVK, and would be happy to show you the choices I made, and the reasons why I think they were the best (EVERYONE thinks their choices were the best!!). I can also show you the RV next door, whose owner made different choices! I'd also be happy to share my opinions with you; understand that free advice is worth what you paid for it.
I can also offer a short, free ride, if you want to see the stuff (or the plane- it's an RV10) in action.
Bob

Just two pennys.

You will have a lot of time while building. Take your time and learn as much as you can about the two or three biggest glass panel builders products. If you need to get bear bones VFR to start with. You can add to a basic system as you get to know what you need down the road after you get flying. Many do just that and it sometimes is a good thing as you learn what you can use and may need or can handle after you get flying to match your type of fling. Not every one does the same type of program in the end. Just a thought.
Yours, R.E.A. III # 80888

Thanks, everyone. These replies make sense. Looks like I have a lot of studying/research ahead of me, and a lot of time to do it. Plenty of variables to optimize for: Panel space, weight, cost, redundancy. I'd like to kill multiple birds with one box where possible to keep weight down and simplify, but then again you want redundancy for some critical instruments. It might be nice to one day do my IFR training in this airplane, but it would be faster and cheaper to just get a VFR panel up and running first and see what materializes later. Then again, I imagine it's painful to do a major re-fit of your panel after everything is done, so maybe you want to plan for your eventual mission right from the start. No easy answers.

Bob, I would love to take you up on your offer for information. Maybe we can connect at the next EAA663 meeting next month (I have not been good about attending recently). I've "toured" a lot of in-progress RVs to learn about building but have not really seen many flying ones yet or even flown in one.

Ryan,
I sent you an email.
Bob

Keep building and don't waste too much time on EFIS or avionics until you are really ready to build the panel. Delay buying as long as possible before making a decision. For sure things will change, EFIS will get better and/or cheaper. Sun-fun and Oshkosh might bring special sales (you can get without attending).

Approaching Jan 2020 there may be a rush on ADB-S Out compliant Transponders and GPS. The might cause a shortage? Doubt it, but it crossed my mind.

ADS-B "in" is optional, but really a no brainer, gives you something tangible like Weather and Traffic without subscription or fancy TCAS (with cost out of reach of GA airplanes). You can get fairly inexpensive ADS-B "in" receiver which has bluetooth or wifi connection to your portable tablet. ADS-B "out" is your transponder blindly transmitting your flight data (alt, speed, position...). This is mandatory if you want to fly in most of the airspace (not required in Class G airspace or some class E below 10K MSL I recall).

You don't have to buy fancy gear, many people still go with simple portable GPS or iPad based EFIS/Map.... however for ADB-S "out" requires compliant transponder and GPS source at minimum. Don't buy any older mode-C transponder, it will be a door stop after Jan 2020. Some late model transponders can be upgraded but it is not cheap.

A panel mounted $12,000-$15,000 EFIS (e.g., Garmin, Dynon) system, integrated flight instrument, map, engine monitoring, Com radio, transponder and even auto-pilot is pretty awesome. As was said, there are a mind boggling number of options. I love the idea of touch screen. Touch airport, get charts, push the Com frequency into the radio without turning a dial (but pushing a few buttons). Overlay weather and traffic on your map (with terrain information) is neat. Do you need that to fly around the airport?

I'm making the same decisions and about the same place with my RV-7. My first decision is brand. Garmin I thought woulld be overpriced, but now see their G3X line is very competitively priced. Dynon is very good. GRT Avionics is good as well. There are at least 2 or 3 other players. I want a brand/system that will not go obsolete with good support for foreseeable future. Good luck!

gmcjetpilot said:

. Don't buy a older mode-C transponder, likely it will be a door stop after Jan 2020.
re.

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Generally good advice EXCEPT for the above exerpt. ADSB-out is complicated, but generally speaking you have 3 options.
1. Do nothing and avoid ADSB required (2020) airspace. This won?t work for the OP as KLVK is in required airspace.
2. Buy a mode S-ES transponder (and suitable gps). This is a good option.
3. Buy one of those ?door stop? mode C transponders, currently dirt cheap on the used market, and install a 978 MHz UAT for ADSB. This is also a good option.

2 and 3 are currently very similarly priced. Make your choice based on small differences that may be important to you as an individual.

One other.

Just one other thing. Most of us have found that it is a good idea to get your avionics at the very end of your build time. This stuff changes so fast, there will be something better, faster and cheaper in three to six months from now.
Yours, R.E.A. III # 80888

Draker said:

It might be nice to one day do my IFR training in this airplane, but it would be faster and cheaper to just get a VFR panel up and running first and see what materializes later. Then again, I imagine it's painful to do a major re-fit of your panel after everything is done, so maybe you want to plan for your eventual mission right from the start.

Click to expand...

If you even think you may want to get your IFR ticket in the future and or you want to expand your audience for resale possibility down the road, it is very easy and desirable to go ahead and plan for the certified IFR navigator up front. You can purchase the connectors and the tray for fairly cheap and go ahead and install provisions to slide one in at a future date. Basically you could plan for your panel to be plug and play expandable in stages in the future for very little extra $. It is a bit more work but to do it up front would take way less time than ripping into a finished panel and adding those options later.

Brantel said:

If you even think you may want to get your IFR ticket in the future and or you want to expand your audience for resale possibility down the road, it is very easy and desirable to go ahead and plan for the certified IFR navigator up front. You can purchase the connectors and the tray for fairly cheap and go ahead and install provisions to slide one in at a future date. Basically you could plan for your panel to be plug and play expandable in stages in the future for very little extra $. It is a bit more work but to do it up front would take way less time than ripping into a finished panel and adding those options later.

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I like this idea a lot. Didn't even think of simply leaving room for something I wasn't planning to purchase/install right away.

Will definitely delay the avionics decisions to the very end, as everyone advises!

Are there any points in the fuselage build where making a decision on future avionics choices would change what I should do during the build? For example, I read that when building the firewall, if I'm sure I'm going with a fuel injected engine, I don't need that fuel pump doubler plate.

Robert Anglin said:

Just one other thing. Most of us have found that it is a good idea to get your avionics at the very end of your build time. This stuff changes so fast, there will be something better, faster and cheaper in three to six months from now.
Yours, R.E.A. III # 80888

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IMHO...That advise was true in the past but not now.

Experimental avionics has matured significantly and the changes are not coming as fast as they once were. AND many of the changes will be in the form of a software upgrade.

Even if there is an upgrade that you might miss by buying sooner rather than later...holy mackerel...the current systems are more capable then most transport category aircraft as it is.

The issue of the warranty clock ticking holds more sway for me than the fear I might miss out on some wiz bang feature who's need is dubious.

Draker said:

Are there any points in the fuselage build where making a decision on future avionics choices would change what I should do during the build? For example, I read that when building the firewall, if I'm sure I'm going with a fuel injected engine, I don't need that fuel pump doubler plate.

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The AP pitch servo bracket is one item that you might want to do now. It can be installed in a finished plane but it is easier when building.

Other stuff like provisions for antennas and coax cables are also something to think about. It seems like the holes called out in the plans are never enough.

These days you may have NAV, COM, GS, MB, GPS, Xponder, ADS-B, APRS, ELT antennas to deal with and you may want some of them to be aft of the wing spar so plan on those coax cables.

Some people mount AHRS's and other LRU's like remote xponders in the area aft of the baggage bulkhead. Plan for those wires and pitot/static/aoa tubes if you want to do that. Most people put the magnetometers in the tail.

Avionics have to share cable pathways with stuff like lights so plan accordingly.