Upgrade Help- VFR to IFR

SkyhawkC172

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SkyhawkC172
Hey everyone, new pilot (just received my PPL last week) and looking to upgrade my Cessna 172 to IFR to continue progressing. I've been looking specifically at the Garmin GPS 175, GNC 355, GNX 375, or GTX 650(xi?), and making sure that my full avionics stack is fully compliant and can be used for an IFR checkride. My goal is to fly VFR the majority of time but use IFR as needed. Avidyne is out of my price range and I'd rather not buy a radio that is no longer supported (ie Garmin 430). I'd greatly appreciate recommendations to update my avionics stack considering my existing equipment.

My understanding reading the regulations is that I need to have redundant Comms systems and navigation, including precision and non-precision approaches though admittedly I'm still trying to understand the rules.

My primary airport is within the Mode C veil of a large airport so ADS-B Out is always required. I don't have a PFD and rely on analog gages. I do have room in my avionics stack for larger equipment if necessary.

My current avionics stack includes the following:
-Garmin GNC-300XL NavComm
-TKM MX11 Comm Receiver
-King KN-53 VOR-ILS NAV Receiver
-Garmin GTX 335 Transponder with ADS-B Out
-External Sentry unit with Foreflight (iPad) for ADS-B In/Out

Largest factors are cost and usability. I could maybe spring for the GTX 650 if I could find a reasonably priced used one, but if I don't need that much horsepower then I'm fine not spending that kind of money. Also, if anyone has feedback on the usability of the 175/355/375 with the 2" screen while flying IFR it would be greatly appreciated! Thanks in advance
 
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You do not need dual nav coms to fly IFR, but you will want them. :) You actually have an OK panel now

The 650 is an amazing piece of equipment and can be the basis for a very high end panel. If you do a 650, you can keep your GNC-300 and have dual GPS with a single VOR/LOC.

Actually, for more bang for your buck, I would first put in a G-5 HSI. And HSI gives you about 80% of the goodness of a glass panel.

Also, you may find yourself flying IFR more than you think. For pretty much any flight over an hour, I file and fly IFR. Just easier. No worries about airspace.
 
You do not need dual nav coms to fly IFR, but you will want them. :) You actually have an OK panel now

The 650 is an amazing piece of equipment and can be the basis for a very high end panel. If you do a 650, you can keep your GNC-300 and have dual GPS with a single VOR/LOC.

Actually, for more bang for your buck, I would first put in a G-5 HSI. And HSI gives you about 80% of the goodness of a glass panel.

Also, you may find yourself flying IFR more than you think. For pretty much any flight over an hour, I file and fly IFR. Just easier. No worries about airspace.
Thank you. So your recommendation is to find a reasonably priced 650 instead of the other options?

Interesting thought on the G5 HSI. I haven't looked too much into it...I've accustomed to the analog gages but may upgrade to a glass panel at a future date.

Good to know about IFR. As I stated above, my primary airport is under a Bravo and there are plenty of Deltas and Charlies nearby. I may use IFR more often than I anticipate.
 
The smaller 2” has a split keyboard for entering your waypoints which was not as ideal as the 650 and the 650 has the comm/nav built in.

@Pinecone can you tell me more about the use for the second nav radio? I was going to get 2 comms and 1 nav in my upgrade. I never used 2 nav radios before and barely used the second comm before except for weather or monitoring 121.5.
 
If you were interested in a larger screen and similar features, here is an option for about the same(ish) cost.

 
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I have a 175 and it is great unit, but I would agree the screen/keyboard is a little smaller than ideal when it’s bumpy.

I find that I typically make changes in ForeFlight, which syncs to the 175 via Bluetooth. I find the ForeFlight interface far more intuitive.

Garmin has a nice iPad based simulator for their navigators. I would download it and play around with it before you make a choice. The simulator is (pretty sure) exact size.


And congrats!
 
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IFDs have a free app that will mirror the screen onto an iPad. You get to choose the size and location of that mirror. I think that's the best UI/UX solution on the market.
 
I have a 175 and it is great unit, but I would agree the screen/keyboard is a little smaller than ideal when it’s bumpy.

I find that I typically make changes in ForeFlight, which syncs to the 175 via Bluetooth. I find the ForeFlight interface far more intuitive.

Garmin has a nice iPad based simulator for their navigators. I would download it and play around with it before you make a choice. The simulator is (pretty sure) exact size.


And congrats!
Thank you, I was unaware of the simulator. I'll give that a shot.

I have a Sentry that connects to Foreflight via wifi, and if the 175 is on Bluetooth then I think it should all sync together on my iPad? I use Foreflight for general navigation right now anyways with my 300XL

Can you control your 175 with the iPad through Foreflight or do you still need to operate on the 175 screen? In other words, if you sync your iPad up via Bluetooth does it function as a larger screen for the 175?
 
If you were interested in a larger screen and similar features, here is an option for about the same(ish) cost.

Thank you. This looks like a really nice unit but with installation costs is likely out of my price range
 
Can you control your 175 with the iPad through Foreflight or do you still need to operate on the 175 screen? In other words, if you sync your iPad up via Bluetooth does it function as a larger screen for the 175?
For most of what you probably want to do, yes.

Also, the you can spin the knobs for data entry on a 175 like it's a 430.
 
The smaller 2” has a split keyboard for entering your waypoints which was not as ideal as the 650 and the 650 has the comm/nav built in.

@Pinecone can you tell me more about the use for the second nav radio? I was going to get 2 comms and 1 nav in my upgrade. I never used 2 nav radios before and barely used the second comm before except for weather or monitoring 121.5.
I am old school. Prefer two comms and two navs. Best would be two 650s or a 750Xi and 650Xi combo. That gives you two comms, two GPSes, two navs and two screens to display info.

But currently, you can do your instrument rating with GPS only (with WAAS). But I would not fly IFR that way. Too many reports of GPS issues. Had one at local field. Two planes reported inability to get a GPS lock on. Maybe solar flares.

In the old days, you needed two navs to be able to ID fixes by crossing radials. Could be done single nav, with LOTS more work.

Look into what an HSI does. First time I flew with an HSI and did not have to visualize in my head I thought I had ended up in pilot heaven when it came to avionics. :D
 
Hey everyone, new pilot (just received my PPL last week) and looking to upgrade my Cessna 172 to IFR to continue progressing. I've been looking specifically at the Garmin GPS 175, GNC 355, GNX 375, or GTX 650(xi?), and making sure that my full avionics stack is fully compliant and can be used for an IFR checkride. My goal is to fly VFR the majority of time but use IFR as needed. Avidyne is out of my price range and I'd rather not buy a radio that is no longer supported (ie Garmin 430). I'd greatly appreciate recommendations to update my avionics stack considering my existing equipment.

My understanding reading the regulations is that I need to have redundant Comms systems and navigation, including precision and non-precision approaches though admittedly I'm still trying to understand the rules.

My primary airport is within the Mode C veil of a large airport so ADS-B Out is always required. I don't have a PFD and rely on analog gages. I do have room in my avionics stack for larger equipment if necessary.

My current avionics stack includes the following:
-Garmin GNC-300XL NavComm
-TKM MX11 Comm Receiver
-King KN-53 VOR-ILS NAV Receiver
-Garmin GTX 335 Transponder with ADS-B Out
-External Sentry unit with Foreflight (iPad) for ADS-B In/Out

Largest factors are cost and usability. I could maybe spring for the GTX 650 if I could find a reasonably priced used one, but if I don't need that much horsepower then I'm fine not spending that kind of money. Also, if anyone has feedback on the usability of the 175/355/375 with the 2" screen while flying IFR it would be greatly appreciated! Thanks in advance
Talk to the CFII you will be using and have them give you their thoughts on training in your plane with the avionics as they are now. I’m no expert on everything you have now, but it appears you already have the ability to fly ILS, LOC, VOR, and GPS/RNAV approaches. You didn’t give any info on your attitude indicator and backup, HSI, etc for displaying the info from your avionics. If you’re already legal to complete your IFR training as is, don’t spend money on unnecessary upgrades now. After you complete training you will have a better understanding of what’s useful vs a good looking waste of money.
 
Thank you, I was unaware of the simulator. I'll give that a shot.

I have a Sentry that connects to Foreflight via wifi, and if the 175 is on Bluetooth then I think it should all sync together on my iPad? I use Foreflight for general navigation right now anyways with my 300XL

Can you control your 175 with the iPad through Foreflight or do you still need to operate on the 175 screen? In other words, if you sync your iPad up via Bluetooth does it function as a larger screen for the 175?
In the scenario I am describing, you are not controlling the 175 via the iPad - but rather interacting with ForeFlight. The iPad connects with the 175 via Bluetooth and keeps the iPad and the 175 flight plan in sync. You can make a change in either system (175 or ForeFlight) and the change will persist across both devices.

Having multiple devices connected has not been an issue for me. I use an iPhone vs an iPad - but…I have dual Dynon HDX connected to the phone via WiFi, the 175 connected via Bluetooth. Works terrific.
 
Talk to the CFII you will be using and have them give you their thoughts on training in your plane with the avionics as they are now. I’m no expert on everything you have now, but it appears you already have the ability to fly ILS, LOC, VOR, and GPS/RNAV approaches. You didn’t give any info on your attitude indicator and backup, HSI, etc for displaying the info from your avionics. If you’re already legal to complete your IFR training as is, don’t spend money on unnecessary upgrades now. After you complete training you will have a better understanding of what’s useful vs a good looking waste of money.
Good advice. I did speak to my CFII and he didn't have a strong opinion. He's used to a 650 but said he'll become familiar with any system.

I can fly ILS, LOC, VOR, and GPS with my 300XL but the 300XL doesn't have WAAS so it's not legal for IFR. My attitude indicator is a standard gyro. All of my gages are vacuum or gyro- nothing interacts with the avionics currently outside of the connection to the CDI/OBS
 
In the scenario I am describing, you are not controlling the 175 via the iPad - but rather interacting with ForeFlight. The iPad connects with the 175 via Bluetooth and keeps the iPad and the 175 flight plan in sync. You can make a change in either system (175 or ForeFlight) and the change will persist across both devices.

Having multiple devices connected has not been an issue for me. I use an iPhone vs an iPad - but…I have dual Dynon HDX connected to the phone via WiFi, the 175 connected via Bluetooth. Works terrific.
Okay that makes sense. So if you're flying IFR, you're still interacting with the 175 screen and coordinating the approach...it just shows up on the iPad through Foreflight. Is that right? You can't do the approach sequence through Foreflight.

I would have something similar- Sentry ADS-B in through Wifi, 175/335/375 through bluetooth - though I don't have the digital setup you do...frankly, I don't have any digital gages
 
I think I have my path forward...would appreciate feedback if I'm overlooking a glaring issue with regards to being legal for IFR

I think I'm going to go with Option 2- remove the TKM MX11 Comm Receiver and go with a GNC 335 NAVCOMM and a G5 with HSI. It's marginally cheaper than the 650 alone but provides the additional glass cockpit-like features from the G5 with HSI. I can also coordinate everything through Foreflight/iPad. Option 2 has less redundancy with single ILS and VOR, but since those are technologies being sunsetted I'm not as concerned about it. I have never had a GPS outtage in my area.

Thank you to everyone, especially @Pinecone and @Learnin’ to fly… , for your personal experiences.

OPTION 1- 650 with existing equipment (keep 300XL and ILS/VOR Receiver, removal of COMM and Sentry)OPTION 2- 335 with existing equipment (keep 300XL and ILS/VOR receiver, removal of COMM)
Dual COMMDual COMM
Dual GPSDual GPS
Dual ILSSingle ILS
Dual VORSingle VOR
Built-in ADS-B IN/OUTSentry ADS-B IN through iPad (Foreflight), use existing transponder for ADS-B OUT
G5 w/ HSI
TOTAL COST (BEFORE INSTALL)- $11kTOTAL COST (BEFORE INSTALL)- $10.8k ($10.4k with mail-in rebate)
 
Your 300XL is a IFR GPS.
Keep what you have and get your ticket.
Then once you know what you don’t know now, do the upgrade, if you keep the plane.
 
Good advice. I did speak to my CFII and he didn't have a strong opinion. He's used to a 650 but said he'll become familiar with any system.

I can fly ILS, LOC, VOR, and GPS with my 300XL but the 300XL doesn't have WAAS so it's not legal for IFR. My attitude indicator is a standard gyro. All of my gages are vacuum or gyro- nothing interacts with the avionics currently outside of the connection to the CDI/OBS
IFR approaches break down into two basic types (precision and non precision). Flying a GPS based precision approach is no different than flying an ILS, once you set up the approach in your GPS/Nav system (or FMS, or whatever you have in a given aircraft). Non precision approaches are likewise no different (GPS, LOC, VOR, NDB, etc). The two basic things you are learning are how to navigate the airspace system regardless of outside visibility and how to shoot a precision/nonprecision approach. Learning to do this on a basic six pack will pay dividends as it forces you to build your own SA of where you are in time and space. Once you’ve mastered this and have a better idea of what your “mission requirements” are you will be ready to make wise choices on a panel update.

Save your money for now and spend it on avgas and quality instruction.
 
Okay that makes sense. So if you're flying IFR, you're still interacting with the 175 screen and coordinating the approach...it just shows up on the iPad through Foreflight. Is that right? You can't do the approach sequence through Foreflight.

I would have something similar- Sentry ADS-B in through Wifi, 175/335/375 through bluetooth - though I don't have the digital setup you do...frankly, I don't have any digital gages
Yep - i build the flight plan in ForeFlight in planning, it syncs to the 175 and make any route modifications there.

You can load/activate/modify the approach in ForeFlight (i dont think you can go missed - maybe you can) but I feel those steps are best done on the 175.

In ForeFlight, after you enter your airports/route - click procedures and add the approach to your flight plan. Once it’s in your flight plan - tap the approach and it gives you the menu to activate, activate vectors, etc, etc.

In the end, either place you make a change (FF or the 175) the other is updated. I am personally of the view that once you are activating the approach - you are best doing that on the 175. It makes more sense in a flow, and eliminates a failure point (Bluetooth) at a critical phase.
 

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Hey everyone, new pilot (just received my PPL last week) and looking to upgrade my Cessna 172 to IFR to continue progressing. I've been looking specifically at the Garmin GPS 175, GNC 355, GNX 375, or GTX 650(xi?), and making sure that my full avionics stack is fully compliant and can be used for an IFR checkride. My goal is to fly VFR the majority of time but use IFR as needed. Avidyne is out of my price range and I'd rather not buy a radio that is no longer supported (ie Garmin 430). I'd greatly appreciate recommendations to update my avionics stack considering my existing equipment.

My understanding reading the regulations is that I need to have redundant Comms systems and navigation, including precision and non-precision approaches though admittedly I'm still trying to understand the rules.

My primary airport is within the Mode C veil of a large airport so ADS-B Out is always required. I don't have a PFD and rely on analog gages. I do have room in my avionics stack for larger equipment if necessary.

My current avionics stack includes the following:
-Garmin GNC-300XL NavComm
-TKM MX11 Comm Receiver
-King KN-53 VOR-ILS NAV Receiver
-Garmin GTX 335 Transponder with ADS-B Out
-External Sentry unit with Foreflight (iPad) for ADS-B In/Out

Largest factors are cost and usability. I could maybe spring for the GTX 650 if I could find a reasonably priced used one, but if I don't need that much horsepower then I'm fine not spending that kind of money. Also, if anyone has feedback on the usability of the 175/355/375 with the 2" screen while flying IFR it would be greatly appreciated! Thanks in advance
your panel is fine the way it is, i'd go with that until i had a bit of experience.
 
Good advice. I did speak to my CFII and he didn't have a strong opinion. He's used to a 650 but said he'll become familiar with any system.

I can fly ILS, LOC, VOR, and GPS with my 300XL but the 300XL doesn't have WAAS so it's not legal for IFR. My attitude indicator is a standard gyro. All of my gages are vacuum or gyro- nothing interacts with the avionics currently outside of the connection to the CDI/OBS
300xl is absolutely capable of ifr, waas only get's you tighter tolerances and lpv approaches. start your IR training, you'll see how it all works. I nitially started with just 2 nav/comms, no gps at all.
 
To get the maximum utility out of your IFR rating (especially if flying to non-metro airports), it would be helpful to have LPV capability. Almost everywhere has an LPV approach a that gets you to near ILS minimums these days. I also think that a pair of G5s (or similar) is a terrific safety upgrade. It is very easy to fly procedures with EFIS, especially if you have an AP. One option is to replace your GNC 300XL with a GNC 355. That would likely be completely compatible with a future modern EFIS and AP install. But you have plenty of capability now. The one capability you don't have now is an AP, which can be very useful for single pilot IFR. Once you have the IFR rating, you may find you wind up filing often, especially in MVFR conditions. The IFR rating takes all of the indecision and stress out of flying in MVFR conditions.

My IFR upgrade sequence was this: (1) WAAS GPS (GNS-430), (2) autopilot (STEC-20), (3) EFIS (dual G5s). (Somewhere in there an NGT-9000 got installed to comply with ADS-B in/out.) I'm about to come full circle and replace the WAAS GPS with something more modern when the GNS-430 becomes unrepairable, and then the autopilot with something with altitude hold. Each of these upgrades were a significant safety-of-flight improvement, and makes IFR flight easier to manage.
 
How long will you have the plane? If “for a while”, pay a little more and get the GTN650xi. If too much, the GNC option is fine. In any event, skip the G5 for now. Save up and get dual G 275s
 
Has anyone had any experience with a recent AP install? I'm curious whether the conventional wisdom of the total install cost being roughly double the baseline cost of the avionics holds true.

Edit: Disregard. Did a bit of searching and found some posts from April of this year. Sounds like total cost is at least double the price of the AP. Guess I'll keep saving!
 
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How long will you have the plane? If “for a while”, pay a little more and get the GTN650xi. If too much, the GNC option is fine. In any event, skip the G5 for now. Save up and get dual G 275s
This plane will probably be ours forever. I don't really have any inspiration to expand to a larger plane.

I'm curious why you'd recommend the GTN650xi over the 355? I could quite literally buy two 355s for one 650xi, and I don't see the appeal of the 650 with VOR and ILS since those are being phased out (plus I already have VOR/ILS capabilities). I'm not sure what I'm missing out on when people recommend the 650, and I'm afraid I'm overlooking something
 
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Do you mean GNC 355? Garmin Com with GPS Nav?

The Garmin 335 is a transponder, no com or GPS.

BTW - it’s the transponder that provides ADSB out (and “In” on certain models like the Garmin 345). In your post above you list option 1 and 2, and list ADSB in and out as feature of Option 1, but I don’t see any change in transponders.
 
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Do you mean GNC 355? Garmin Com with GPS Nav?

The Garmin 335 is a transponder, no com or GPS.

BTW - it’s the transponder that provides ADSB out (and “In” on certain models like the Garmin 345). In your post above you list option 1 and 2, and list ADSB in and out as feature of Option 1, but I don’t see any change in transponders.
My apologies, yes the GNC 355 NAVCOMM. Darn Garmin and their similar numbering scheme! I'll revise my post to clarify.

 
This plane will probably be ours forever. I don't really have any inspiration to expand to a larger plane.

I'm curious why you'd recommend the GTN650xi over the 355? I could quite literally buy two 355s for one 650xi, and I don't see the appeal of the 650 with VOR and ILS since those are being phased out (plus I already have VOR/ILS capabilities). I'm not sure what I'm missing out on when people recommend the 650, and I'm afraid I'm overlooking something
Personally, if money was a factor, I wouldn't hesitate to go the GNC 355 route. What you want is WAAS GPS capability to maximize your IFR capability. If you really want to use that IFR rating, you will likely find you want to get to a WAAS/AP/EFIS configuration, probably in that order. What you want to ensure to the extent you can is to do this in a way that all of the upgrades will be compatible with one another. You don't want to be stuck with a GPS that can't talk to a future AP or EFIS (or your ADS-B in solution). I can tell you that since installing my GNS-430 around 20 years ago, I have not used a VOR to navigate anywhere except for IPCs or other recurrent training. It's GPS NAV and either an ILS or LPV approach at the destination 90% of the time. I can't even remember the last time I flew a plain LNAV approach for real.
 
Hey everyone, new pilot (just received my PPL last week) and looking to upgrade my Cessna 172 to IFR to continue progressing. I've been looking specifically at the Garmin GPS 175, GNC 355, GNX 375, or GTX 650(xi?), and making sure that my full avionics stack is fully compliant and can be used for an IFR checkride. My goal is to fly VFR the majority of time but use IFR as needed. Avidyne is out of my price range and I'd rather not buy a radio that is no longer supported (ie Garmin 430). I'd greatly appreciate recommendations to update my avionics stack considering my existing equipment.

My understanding reading the regulations is that I need to have redundant Comms systems and navigation, including precision and non-precision approaches though admittedly I'm still trying to understand the rules.

My primary airport is within the Mode C veil of a large airport so ADS-B Out is always required. I don't have a PFD and rely on analog gages. I do have room in my avionics stack for larger equipment if necessary.

My current avionics stack includes the following:
-Garmin GNC-300XL NavComm
-TKM MX11 Comm Receiver
-King KN-53 VOR-ILS NAV Receiver
-Garmin GTX 335 Transponder with ADS-B Out
-External Sentry unit with Foreflight (iPad) for ADS-B In/Out

Largest factors are cost and usability. I could maybe spring for the GTX 650 if I could find a reasonably priced used one, but if I don't need that much horsepower then I'm fine not spending that kind of money. Also, if anyone has feedback on the usability of the 175/355/375 with the 2" screen while flying IFR it would be greatly appreciated! Thanks in advance

The 300XL is IFR legal, I think you have everything that you need.

Someone else asked about AP installation, my equipment is 14k for the gfc500 with autotrim add-on and approx 4600 to install it for 18,600.

It was pretty costly to wire existing equipment to new equipment so keeping everything new and Garmin I think saved on labor.

How’s your vacuum system? Do you want 2 x G5’s or 275s?

Maybe see if you can sell your 335 and get a 345 with adsb in/out. Unless you are fine with your 335.

Redundant comms is not required, but it’s desired. I’m only going with 1 nav radio too, I’ve never used a second one and I’m already over my budget. I thought about keeping my 300XL and KX155 but the labor costs to wire them into the new system were more than the costs to just buy the second nav radio.

Do you have an autopilot?

What’s your budget?
 
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My apologies, yes the GNC 355 NAVCOMM. Darn Garmin and their similar numbering scheme! I'll revise my post to clarify.

Got it!

So I trained on planes with a GTN 650, and bought a plane in June with a GNC 355. I’m sending this plane to the avionics shop next week to install an AutoPilot, dual G275s, and a GTN 650xi. I’m keeping the GNC 355 as a GPS back up and second com.

Yes, I like the bigger screen and the few additional capabilities that much that I’m buying a GTN 650xi.

But…. If you only have a certain budget, the GNC 355 would be just fine. Add the GTN 650xi later if you like.

As ancient as the 300XL is, I wonder how long it will be supported / repairable.

Skip the G5s for now until you can budget for G275s.
 
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I was going with the 275s but then decided to go with the G3X and I was told I need a G5 as the standby instead of the 275. I think the 275 is cooler but I’ll learn to live with the G5.
 
Yes, I like the wider screen and the few additional capabilities that much that I’m buying a GTN 650xi.
Taller, not wider. If my math is correct, they are roughly the same width. The GTN does have a higher pixel density, though.
 
I can’t imagine why a G275 couldn’t back up the G3X. Then again, if you’re installing a G3X and only need a back up (which you’d probably never use), a G5 would be just fine.

I’m recommending dual G275s vs dual G5s, assuming G3X isn’t in the mix.
 
Taller, not wider. If my math is correct, they are roughly the same width. The GTN does have a higher pixel density, though.
You are correct. I should have said “bigger” - I corrected my post.
 
I can’t imagine why a G275 couldn’t back up the G3X. Then again, if you’re installing a G3X and only need a back up (which you’d probably never use), a G5 would be just fine.

I’m recommending dual G275s vs dual G5s, assuming G3X isn’t in the mix.
I believe Garmin recommends the G5 with the G3X and the GI275 with the G500, in order to drive the GFC500 A/P?
 
Did not know that - thank you. This is odd, because the GI 275 is perfectly capable to drive the GFC 500 AP.
 
In the past, the GI-275 was not allowed as standby for the G3X based on the STC.

But that changed a while ago and the -275 is now approved.
 
In the past, the GI-275 was not allowed as standby for the G3X based on the STC.

But that changed a while ago and the -275 is now approved.
What about the manual above?

What’s the recommended one?
 
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