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Garmin shopping list for RV8A

jlbpropilot

Active Member
Could someone please suggest to me how they would equip the ideal IFR Garmin panel? I printed off their product sheets but there are so many options that Im confused. Thanks
 
I think the current minimum is:

G3X for EFIS
G5 for backup
GLwhatever-650 for navigator
Standard nav/comm for 2nd radio
Transponder for ADSB

But I'm just trying to sort it out as well, so someone who actually knows something might chime in and correct me.
 
I think this one came out nice...

G3X Touch 460, GTN650, G5, GTR20, GMA245, GTX45R, GMC507, GSA28 servos, GAD29, GAD27, Dual GSU25 ADAHRS

IMG_7756-1200.jpg
 
How about dual nav/comms? Seems like radios are so good these days that one would be OK?
 
Great Panel!

I have a functionally similar panel in m 7A (except no remote devices and dual G3X Touch displays). That is exactly how I would build an 8.
It is at a minimum very convenient (and safer) to have two comm radios. I always need to get weather or listen in to Tower/CTAF before being dumped into busy airspace under IFR. Requesting to leave current ATC frequency to do these things is not realistic to me. I have two and really wouldn't consider going with just one.

It's also a great idea to keep 121.5 tuned the second radio while enroute for those days when you miss a call on frequency or you don't get the call before you run out of coverage on the current frequency. They'll find you on 121.5.

With dual GSU AHRS and the G5 (built-in AHRS) you end up with at least 3 attitude sources in this setup.

Walt will have to chime in on the AHRS count as there may also be a "back up" AHRS in the GTX that can be used on a Garmin portable or an Ipad as a 4th attitude source if really needed.

Andy
 
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I have a functionally similar panel in m 7A (except no remote devices and dual G3X Touch displays). That is exactly how I would build an 8.
It is at a minimum very convenient (and safer) to have two comm radios. I always need to get weather or listen in to Tower/CTAF before being dumped into busy airspace under IFR. Requesting to leave current ATC frequency to do these things is not realistic to me. I have two and really wouldn't consider going with just one.

It's also a great idea to keep 121.5 tuned the second radio while enroute for those days when you miss a call on frequency or you don't get the call before you run out of coverage on the current frequency. They'll find you on 121.5.

With dual GSU AHRS and the G5 (built-in AHRS) you end up with at least 3 attitude sources in this setup.

Walt will have to chime in on the AHRS count as there may also be a "back up" AHRS in the GTX that can be used on a Garmin portable or an Ipad as a 4th attitude source if really needed.

Andy

With dual ADAHRS (GSU25) and the G5 you have 3 sources of attitude/air data available so this gives you the tie breaker if something looks weird.

But having dual GSU25's tied to the G3X also gives you AHRS comparison and fall back capability. If one of the GSU's fail the G3X automaticallly switches to the back up and give you an message that you are now on AHRS #2. The units are also comparing data and will give you a message if something is out of tolerence between the 2.

The G5 will also provide AHRS info to the G3X if both GSU25's fail but is not part of the data comparison like the GSU25's do.

Audio panel with dual coms, yea really convenient to have, this gives you 4 freq's available at the touch of a buttom along with the convenience of listening/monitoring things while not leaving your primary freq. I use the audio panel a lot, wouldn't be without one these days.
 
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I was considering the GTN 650 as the only radio. Do I really need another?

Steve,

Not sure if your bird will be IFR or not. The GTN 650 has a capable radio inside. I am confused as people are talking about installing a GTN 650 or 750 in addition to dual Garmin radios. That sounds like 3 radios to me? I would think a GTN 650 plus an additional Garmin radio would suffice for IFR.

FWIW, I own a Rans S-20 Raven and have it set up for VFR only. I have a Dynon Skyview and one radio. Works well. Sometimes it would be nice to have another radio but seems to work well for me. It has dual watch which enables you to listen to 2 different frequencies at once. If I am talking to ATC on the primary, I can listen to the ATIS on secondary. It biases the primary frequency if their are transmissions on both frequencies simultaneously.

I have been toying with the idea of building an RV set up for IFR and I think A GTN 650 and one additional radio would be adequate. IMO

Best,
Jim
 
Doesn't the GTN 650 or 750 give you that additional comm? Confused.

Yes the 650/750 has full com, if you want dual com you need another radio like the remote mounted GTR20 or panel mount GTR200.

I was considering the GTN 650 as the only radio. Do I really need another?

Nope dont really "need" it, but for a little extra (about 1k) you can have the remote mounted com 2 which comes in handy and makes a great back-up.
 
Yes the 650/750 has full com, if you want dual com you need another radio like the remote mounted GTR20 or panel mount GTR200.



Nope dont really "need" it, but for a little extra (about 1k) you can have the remote mounted com 2 which comes in handy and makes a great back-up.

Well, about $1K for the second radio, but then you also need an audio panel, and it all starts to take up a lot of space on an RV-8 panel. The remote helps that some, although the instrument bay gets pretty full of boxes too.

But my real point was that radios have gotten to be so reliable that I'm not convinced I really need a backup. I lost coms once in a rented 172 because of a dead battery and bad alternator. I have lost coms a few times in my glider because of a dead battery.

I've never had a radio fail in a way that a second one would work.
 
Well, about $1K for the second radio, but then you also need an audio panel, and it all starts to take up a lot of space on an RV-8 panel. The remote helps that some, although the instrument bay gets pretty full of boxes too.

But my real point was that radios have gotten to be so reliable that I'm not convinced I really need a backup. I lost coms once in a rented 172 because of a dead battery and bad alternator. I have lost coms a few times in my glider because of a dead battery.

I've never had a radio fail in a way that a second one would work.

If you don't want an audio panel and just want to use the 650 com, then you need a intercom of some sort which is half the cost of a modern audio panel which has many more features.
 
Well, about $1K for the second radio, but then you also need an audio panel, and it all starts to take up a lot of space on an RV-8 panel. The remote helps that some, although the instrument bay gets pretty full of boxes too.

But my real point was that radios have gotten to be so reliable that I'm not convinced I really need a backup. I lost coms once in a rented 172 because of a dead battery and bad alternator. I have lost coms a few times in my glider because of a dead battery.

I've never had a radio fail in a way that a second one would work.

You don't need an audio panel just for a second com. A switch (for mic/PTT) and an audio mixer (maybe in an intercom) is all you need, especially if the second com's use is mostly for back-up/listen to ATIS.
I honestly don't quite understand the fear of losing com, as a safety issue (dispatch reliability/convenience is another story). After all, ATC won't fly the plane for you. What looks very iffy to me is the loss of nav, in an airplane with only one nav source, in IMC. Then you're hoping ATC can offer you a vector to VMC, or an ASR approach, and hope that it gets you into visual conditions.
 
Well, about $1K for the second radio, but then you also need an audio panel, and it all starts to take up a lot of space on an RV-8 panel. The remote helps that some, although the instrument bay gets pretty full of boxes too.

But my real point was that radios have gotten to be so reliable that I'm not convinced I really need a backup. I lost coms once in a rented 172 because of a dead battery and bad alternator. I have lost coms a few times in my glider because of a dead battery.

I've never had a radio fail in a way that a second one would work.

Bingo!,
Radios have gotten a lot more reliable. Had a few of the old type radios fail but today is a different story. You could also carry a handheld with a provision to connect it to the comm antenna if need be.
 
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