Single GI-275 and G5 stack

WannFly said:
huge.

750 is about 5k more for the hardware, install is same for both units. for that 5k you cant get G3X installed.
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So you mean installing a GTN 650 and G3X instead of a GTN 750?

The 7" G3X touch is $8,000 just for the hardware, and (just a guess) at least that much again for installation.

https://buy.garmin.com/en-US/US/p/682215
 
So a GTN 750, GTX 345, and two GI 275 is a more cost effective solution than a GTN 650, a GTX 345, and a G3X?
Bill Jennings said:
One reason we are happy with two GI275s we are getting vs doing a G3x Touch like screen is having a big fat ipad running foreflight. Most information that a G3 would display is on the iPad, so we're good with NOT having a big expensive chunk of glass on the panel. Looks snazzy, but not nearly as cost effective.
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Sounds good - but the only thing I can think of is the I Pad readability in sunlight vs G3x. BUT... I suppose you could just use an Aera 760 and just use it as display screen showing your map with traffic and weather, as well as bring up charts and what not.

Heck - I think it even talks to a GFC 500 auto pilot, lets you load flight plans to your 650, etc.
 
WDD said:
So a GTN 750, GTX 345, and two GI 275 is a more cost effective solution than a GTN 650, a GTX 345, and a G3X?
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I'd think so, but you'd need a quote from an avionics shop to be sure. That G3X is going to run a lot of AMUs installed.
 
If only they let you do the panel work yourself and just get it inspected / signed off on.
 
WDD said:
If only they let you do the panel work yourself and just get it inspected / signed off on.
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They do, in exp world.... and you can sign off yourself
 
I've generally resisted the idea of retrofit big Navigator screens in little airplanes from a money perspective... and possibly UI perspective. I have had trouble justifying the cost of a 750 in lieu of a 650, considering a "linked" iPad provides a bigger and better moving map display without sacrificing any screen real estate. If you're using an iPad linked to your Navigator, as many of us do these days, you're already using the iPad for re-routes and other edits to your flight plan and pushing them to the panel, so why not keep your moving map display there? I fly behind the 750 regularly and love the big display, however the size is such that it's "nice" but not a game changer. It's not big enough to reasonably accommodate chart views, and it's bigger than you really need for everything other than a pretty good size moving map display. I view it as a more comfortable sectional sofa with recliner seats vs. a single love seat (650).

However, one configuration which could really make sense, at least from the small airplane/cramped panel perspective, would be a full "remote" install with audio panel and transponder remoted onto the 750. At that point you're looking at no increase in overall center stack panel space taken, more or less, and the user can choose what he or she wants to use the screen real estate for at a given time... i.e. audio panel, transponder, etc. That is a pretty sleek way to go, although not particularly inexpensive.

The other downside, of course, is you're hoping that single "big screen" or some other single point of failure (power, etc.) within the GTN 750 doesn't fail and and take out some or all of this functionality. I'd sure hate to lose audio panel, GPS, a nav radio, com radio, and my transponder all in one fell swoop.

I wouldn't rule out a 750 at some point in the future for my little TwinCo, but it's a marginal improvement over the 650 for a pretty big panel investment outlay.
 
Wait - I know how to link foreflight to the GTX 345 transponder. But can you link ForeFlight to your GTN 650 or GTN 430WAAS?

I ask because I link to the transponder to the I pad to get the moving map, traffic and weather. If I link to the 430 WAAS do I get additional features?
 
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Ryan F. said:
The other downside, of course, is you're hoping that single "big screen" or some other single point of failure (power, etc.) within the GTN 750 doesn't fail and and take out some or all of this functionality. I'd sure hate to lose audio panel, GPS, a nav radio, com radio, and my transponder all in one fell swoop.
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it wont take out the entire audio panel, there is failsafe, but i agree one large screen with everything remote mount is a single point of failure. thats why i chose to go with panel mount audio panel and 345, even though i dont touch much of them anymore
 
WDD said:
Wait - I know how to link foreflight to the GTX 345 transponder. But can you link ForeFlight to your GTN 650 or GTN 430WAAS?

I ask because I link to the transponder to the I pad to get the moving map, traffic and weather. If I link to the 430 WAAS do I get additional features?
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You can link your iPad to a GNS 430/530 using the FS210.

You can link your iPad to a GTN 650/750 using the FS210 or 510. You don’t get the wireless database updates to the GTN using the FS210.


Sent from my iPhone using Tapatalk
 
Ah. Thanks ! The plane I rent doesn’t have FS 210. If it did I assume you’d want to link your iPad to the GNS 430 instead of the GTX 345 so that you would get WASS on your IPad FLight AHARs.
 
WDD said:
Ah. Thanks ! The plane I rent doesn’t have FS 210. If it did I assume you’d want to link your iPad to the GNS 430 instead of the GTX 345 so that you would get WASS on your IPad FLight AHARs.
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You could connect at 345 via Bluetooth to the iPad to get AHRS and ADS-B info.

You would connect the iPad to FS210 in 430 so that you can make flight plan changes to the 430 via the iPad. I don’t know if the FS 210 will allow the iPad to do anymore than make flight plan changes. I don’t have any experience with the 210 and 430 combo.


Sent from my iPhone using Tapatalk
 
WDD said:
Ah. Thanks ! The plane I rent doesn’t have FS 210. If it did I assume you’d want to link your iPad to the GNS 430 instead of the GTX 345 so that you would get WASS on your IPad FLight AHARs.
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The GTX 345 will relay the location information from your WAAS GPS (including a 430W), and has its own built-in AHRS that it will also send to your tablet. I'm not sure that ForeFlight uses the AHRS (I have an Android tablet running Garmin Pilot and FltPlan Go), but it should.
 
David Megginson said:
The GTX 345 will relay the location information from your WAAS GPS (including a 430W), and has its own built-in AHRS that it will also send to your tablet. I'm not sure that ForeFlight uses the AHRS (I have an Android tablet running Garmin Pilot and FltPlan Go), but it should.
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Yes, ForeFlight can use the AHRS built into the GTX 345.
 
flyingcheesehead said:
Yes, ForeFlight can use the AHRS built into the GTX 345.
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So that means when I use ForeFlight when it’s tied into the GTX 345, it’s gives a WAAS precise GPS AHARS, moving map, etc?
 
WDD said:
So that means when I use ForeFlight when it’s tied into the GTX 345, it’s gives a WAAS precise GPS AHARS, moving map, etc?
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Yes. In my installation, with a GTN 750, GTX 345, and FS 510, I connect to the FS510 and that gives my iPad TIS-B traffic from the 345, FIS-B weather from the 345, AHRS from the 345 for the synthetic vision view in ForeFlight, and WAAS GPS position from the GTN 750.
 
Why not WAAS GPS position from the GTX 345? After all doesn’t the GTX 345 need to transmit out position with WAAS accuracy even when one doesn’t have a GTN?
 
WDD said:
Why not WAAS GPS position from the GTX 345? After all doesn’t the GTX 345 need to transmit out position with WAAS accuracy even when one doesn’t have a GTN?
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If you bought a GTX 345 but didn't have a WAAS GPS, you'd have to pay extra for a WAAS add-on. I've never heard of anyone who did that, and I don't know if the GTX 345 would still share that position.
 
I assumed the ADSB mandate required a plane to transmit its location and what not with WAAS precision, which means the transponder has to be capable of WAAS precision by itself.
 
WDD said:
I assumed the ADSB mandate required a plane to transmit its location and what not with WAAS precision, which means the transponder has to be capable of WAAS precision by itself.
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In most cases, an ADS-B transponder takes that information from an existing WAAS navigator and retransmits it — it doesn't have to be its own WAAS source.
 
I did the Garmin 375 with G5 Suite. I am happy with it. It took a bit to get the AI calibrated correctly, but I find it to be a great addition.
 
WDD said:
Why not WAAS GPS position from the GTX 345? After all doesn’t the GTX 345 need to transmit out position with WAAS accuracy even when one doesn’t have a GTN?
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WDD said:
I assumed the ADSB mandate required a plane to transmit its location and what not with WAAS precision, which means the transponder has to be capable of WAAS precision by itself.
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If the GPS navigator is WAAS capable then it can be the position source for the ADS-B transponder. There's no need to purchase the internal WAAS GPS extra cost option for the GTX-335 or 345 transponder. This is a very common configuration. In my airplane the GSN 530W navigator is the ADS-B position source for my transponder.

In @flyingcheesehead's airplane the WAAS position source is the GTN 750 navigator, not the transponder.
 
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So much knowledge here, but I don’t see my specific question addressed, so here goes: I am also having problems with my HSI, but we suspect it’s the KI-525A. I’m seriously considering the GI 275 ADAHRS-AP as a replacement. The avionics shop says it is compatible with my KAP140, but we haven’t been able to determine if it will interface with my KLN94. FWIW, there’s a WAAS position source in my GTX345, but I don’t know if that helps.
 
TBalch said:
So much knowledge here, but I don’t see my specific question addressed, so here goes: I am also having problems with my HSI, but we suspect it’s the KI-525A. I’m seriously considering the GI 275 ADAHRS-AP as a replacement. The avionics shop says it is compatible with my KAP140, but we haven’t been able to determine if it will interface with my KLN94. FWIW, there’s a WAAS position source in my GTX345, but I don’t know if that helps.
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Garmin's page for the GI-275 says that it can use the WAAS data from the GTX 345 as a "GPS source", but I think that's for moving map, attitude backup, synthetic vision, etc., not for primary navigation. It doesn't list the KLN-94 GPS navigator specifically among compatible navigation sources, but it would be worth checking with a Garmin dealer or Garmin itself to confirm.
 
TBalch said:
So much knowledge here, but I don’t see my specific question addressed, so here goes: I am also having problems with my HSI, but we suspect it’s the KI-525A. I’m seriously considering the GI 275 ADAHRS-AP as a replacement. The avionics shop says it is compatible with my KAP140, but we haven’t been able to determine if it will interface with my KLN94. FWIW, there’s a WAAS position source in my GTX345, but I don’t know if that helps.
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Looking at page 1-10 (section 1.2.2.2) of the Rev. 3 install manual, it appears that a GPS source is required. Based on page 1-9, section 1.2.2.1, and my existing knowledge of such systems, that is required to do Kalman filtering in the ADAHRS. This CAN be done with a GTX 345 if it has the internal WAAS GPS option, or it can be done with the GI 275's internal GPS if you add a GPS antenna on top of the glareshield.

You'll also want to interface the KLN 94 with it anyway so that you get a CDI when you're using the KLN 94 for navigation. They're not very clear on how that works, but it's bothersome to me that your avionics shop can't determine all of this for you. They should be able to tell you everything I just told you, plus they should be able to reach out directly to Garmin dealer support to get a more definitive answer on the KLN 94 interface.

You may want to spring for a GPS 175 or GNC 355 to replace your KLN 94 anyway. It may communicate an analog CDI, but there's some value in having the Garmin digital interface to the GPS. That way, the GI 275 is able to be fully aware of the flight plan, auto-slewing to the new courses as they become active and such. Plus, you'll gain WAAS approach capability, a much nicer/newer/faster unit with a better map presentation, and a warranty.
 
TBalch said:
So much knowledge here, but I don’t see my specific question addressed, so here goes: I am also having problems with my HSI, but we suspect it’s the KI-525A. I’m seriously considering the GI 275 ADAHRS-AP as a replacement. The avionics shop says it is compatible with my KAP140, but we haven’t been able to determine if it will interface with my KLN94. FWIW, there’s a WAAS position source in my GTX345, but I don’t know if that helps.
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This is a bit of a 3 part question.

First, as @flyingcheesehead points out the GI275 needs a WAAS source for the ADAHRS which can either be your GTX345 or it can be internal via an antenna on your glareshield. I think you've got this part covered.

The second part is CDI/HSI (and by extension, autopilot) functionality. The KLN94 is not in the list of interfaces on Garmin's consumer-facing website. However, the KX165 is on the list. That normally talks to a KI206 via up/down/left/right/to/from/flag signals. The KLN94 can also talk to a KI206 via left/right/to/from/flag signals (no WAAS means no up/down). Thus, one can infer that the GI275 is capable of understanding KLN94 guidance signals. I'd guess that this part is "probably". However, I don't have access to a GI275 install manual which could place a hard restriction on this route so you'll have to defer to your Garmin dealer.

The third part is moving map functionality, specifically overlaying a course line, approaches, holds, etc from your flight plan. There are 3 ways of doing this: ARINC429, MapMX over RS232 and GPS-Aviation format over RS-232. The KLN94 doesn't have ARINC429 so that's a no-go. MapMX is Garmin's proprietary format so that's also a non-starter. The KLN94 can output GPS-Aviation over RS232, but that format is limited in the information that it can carry compared to the other two (e.g. I don't think it's capable of drawing approaches and holds). Given that all of the GPS units on the list of interfaces on Garmin's consumer-facing website are capable of both ARINC429 and MapMX, I'd guess that Garmin probably doesn't have any reason to support GPS-Aviation over RS232. Again, I don't have the GI275 install manual so you'll again have to defer to your Garmin dealer.
 
I wish that the GI 275 install manual was somewhere to be found online to look at the details..

I'm thinking of replacing the turn coordinator in my dual-G5 panel with a GI 275 ADI as a first step. I believe, could be wrong, that a TC can be replaced with an attitude indicator if that AI or the existing AI has a battery (different sources of power). In this case, both have a battery. That leaves the original airspeed indicator, altimeter, and vertical speed indicator, which I think satisfies the requirements of both G5 STC and the GI 275 ADI.

As step #2 of easing into the GI 275 world, the Standby MFD (battery+adahrs) could take out the airspeed indicator and the altimeter, leaving only the vertical speed indicator. A 5-pack: 2 G5, 2 GI 275, 1 VSI. Just 4 batteries to maintain ;)
 
This is an older thread, but I thought I'd chime in with my experience. I just installed two G5s and upgraded my GTN635 to a GTN650xi w/fs510. My plane also has a GTX345 transponder. Previously I would fly with foreflight connected to the 345. I could use the map on the 635, but it never seemed as good as the portable displays. Now I find myself flying without the ipad often. The magenta (or green line) on the G5 HSI tells me where to steer. The display on the 650xi is incredible and on par with GP on an ipad. I typically do plug in my ipad with GP for my flights. But now I feel like its much more optional than before. The built in panel feels complete. Add terrain alerting (not proximity) and you have a pretty awesome system. And lastly, the visual approaches show up on the G5s just like a real RNAV/ILS approach does. So even if I'm just in the pattern or jumping between airports in VFR, I'm using it. I think its great practice and reinforces consistent behavior.
 
smounic said:
This is an older thread, but I thought I'd chime in with my experience. I just installed two G5s and upgraded my GTN635 to a GTN650xi w/fs510. My plane also has a GTX345 transponder. Previously I would fly with foreflight connected to the 345. I could use the map on the 635, but it never seemed as good as the portable displays. Now I find myself flying without the ipad often. The magenta (or green line) on the G5 HSI tells me where to steer. The display on the 650xi is incredible and on par with GP on an ipad. I typically do plug in my ipad with GP for my flights. But now I feel like its much more optional than before. The built in panel feels complete. Add terrain alerting (not proximity) and you have a pretty awesome system. And lastly, the visual approaches show up on the G5s just like a real RNAV/ILS approach does. So even if I'm just in the pattern or jumping between airports in VFR, I'm using it. I think its great practice and reinforces consistent behavior.
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Do you need a radar altimeter for terrain alerting? My 750 Xi is currently set up as terrain proximity. I often wonder what the diff is other than call out like 30 feet, 20 feet before touchdown
 
WannFly said:
Do you need a radar altimeter for terrain alerting? My 750 Xi is currently set up as terrain proximity. I often wonder what the diff is other than call out like 30 feet, 20 feet before touchdown
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No, it uses the GPS altitude and terrain database to provide height above terrain. The terrain alerting is a subset of TAWS B functionality that Garmin provides for free. Main requirement to enable it is you have to connect the audio output from the main connector to an unswitched, unmuted input on the audio panel. So you'll get a number of potential callout warnings if it feels they are warranted like negative climb rate ("Don't sink"), excessive decent rate ("Sink Rate"), premature descent alert ("Too Low Terrain"), etc. The only altitude callout you'll get from terrain alerting is the 500' callout ("Five Hundred") any additional callouts would be provided by a radar altimeter or something like the landing height system (NORSEE approved laser altitude thing).
 
Ryan Klems said:
No, it uses the GPS altitude and terrain database to provide height above terrain. The terrain alerting is a subset of TAWS B functionality that Garmin provides for free. Main requirement to enable it is you have to connect the audio output from the main connector to an unswitched, unmuted input on the audio panel. So you'll get a number of potential callout warnings if it feels they are warranted like negative climb rate ("Don't sink"), excessive decent rate ("Sink Rate"), premature descent alert ("Too Low Terrain"), etc. The only altitude callout you'll get from terrain alerting is the 500' callout ("Five Hundred") any additional callouts would be provided by a radar altimeter or something like the landing height system (NORSEE approved laser altitude thing).
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i do get the 500' callout, so may be mine is set to terrain alerting, i have to check. never heard the other callouts, have read about them in the manual though. guessing its a good thing. Thanks Ryan, your feedback on this forum has been invaluable
 
smounic said:
This is an older thread, but I thought I'd chime in with my experience. I just installed two G5s and upgraded my GTN635 to a GTN650xi w/fs510. My plane also has a GTX345 transponder. Previously I would fly with foreflight connected to the 345. I could use the map on the 635, but it never seemed as good as the portable displays. Now I find myself flying without the ipad often. The magenta (or green line) on the G5 HSI tells me where to steer. The display on the 650xi is incredible and on par with GP on an ipad. I typically do plug in my ipad with GP for my flights. But now I feel like its much more optional than before. The built in panel feels complete. Add terrain alerting (not proximity) and you have a pretty awesome system. And lastly, the visual approaches show up on the G5s just like a real RNAV/ILS approach does. So even if I'm just in the pattern or jumping between airports in VFR, I'm using it. I think its great practice and reinforces consistent behavior.
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I have the same panel now, it is awesome. I have been watching the forums and people are getting quotes around $14.5k to $18k installed for dual GI275 and its nuts. Each standby battery for those is around $350, IDK how many years they will last but I'd be ****ed if I had to drop $700 on GI275 standby batteries. Since all the instruments are back-mounted replacing the standby batteries looks like a PITA.

That all being said, if they came out with replacement G5 with a screen as nice as the GTN Xi, I'd seriously consider them, but they shouldn't cost more than $250 over what i paid for the ones i have.

Before Xi swap:
upload_2020-12-14_12-24-14.png
 
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Badly wanting an EIS upgrade and with many things to fix in the panel, I mentally tried every way to bring the GI 275 into my G5 world (other than just MFD). This is largely because I'm really satisfied with the G5 stack and didn't feel like going away from them. But in the end, when I added everything up, I decided to drop the big coin for a G3X Touch setup. With the G5(s), GMU 11, GTP 59, and GAD 29B already installed and ready to go, the G3X Touch is the logical upgrade for me.

I was hard set on getting the GI 275 EIS. The EIS system is the same for both GI 275 and G3X Touch (ie. GEA 24). The 10.6" screen adds $4K compared to the GI 275. Add the GSU-25D ADAHRS unit for a little under $2K and a new panel (I was getting a new one either way), and now 100% glass panel and everything is fully supported properly, unlike the G5-GI 275 mixmatch. I think this upgrade is same cost as or less expensive than replacing a G5 stack with a GI 275 stack + EIS. My left-over G5 unit goes into the right panel.

Also, not sure if the GI 275 would count towards the "Technically Advanced Aircraft" definition (61.129(j)) even though it's an amazing unit. The VSI is not primary in it. Although, I saw a pic of a GI 275 VSI as a seperate unit and it looks pretty cool.

For those contemplating the idea of moving towards G3X Touch with standby GI 275 ADI, two things to consider:
1- Battery total operating cost probably 4x+ compared to G5. Worth it for a "standby" unit?
2- Do we know if baro setting is shared between G3X Touch and GI 275 ADI? If not, that would suck. But if so, it means it should share between G5 and GI 275. And what about magnetometer? Having not seen the install manual, I don't know if the standby GI 275 ADI is on the same CAN bus network as the others. Maybe it is.

These are just my thoughts and reasoning I wanted to share in case someone is thinking about this.
 
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Last I heard , the magnetometer cannot be shared between g5 and 275
 
bnt83 said:
I have the same panel now, it is awesome. I have been watching the forums and people are getting quotes around $14.5k to $18k installed for dual GI275 and its nuts. Each standby battery for those is around $350, IDK how many years they will last but I'd be ****ed if I had to drop $700 on GI275 standby batteries. Since all the instruments are back-mounted replacing the standby batteries looks like a PITA.

That all being said, if they came out with replacement G5 with a screen as nice as the GTN Xi, I'd seriously consider them, but they shouldn't cost more than $250 over what i paid for the ones i have.

Before Xi swap:
View attachment 92477
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Very nice looking setup!
What type of autopilot do you have installed, and what drives it?
 
GRG55 said:
Very nice looking setup!
What type of autopilot do you have installed, and what drives it?
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This airplane was built with a Brittain winglever, Since then a DG adapter (amplifier) and radio interface was added, for pennies essentially. Its a pretty decent lateral autopilot but there is no pitch or altitude capability. This airplane is so slow that its really not a big deal.

The 182 has a GFC-500 with the GFC pitch trim, so I get to fly both a legacy vacuum autopilot and the latest and greatest.
 
WannFly said:
Last I heard , the magnetometer cannot be shared between g5 and 275
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Partially true... according to my avionics installer, anyway. Magnetometer -> G5 -> GI275 works. Magnetometer -> GI275 -> G5 doesn't work.
 
bnt83 said:
This airplane was built with a Brittain winglever, Since then a DG adapter (amplifier) and radio interface was added, for pennies essentially. Its a pretty decent lateral autopilot but there is no pitch or altitude capability. This airplane is so slow that its really not a big deal.

The 182 has a GFC-500 with the GFC pitch trim, so I get to fly both a legacy vacuum autopilot and the latest and greatest.
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I have a late generation Century III (Piper Altimatic IIIC) in the Aztec, which is driving me to the GI-275 instead of the G5. No interest in keeping the vacuum gyro and move it to the TC position. If I have to keep the vacuum gyro I might as well just rebuild the gyros and stick with the current 6-pack as is.

There's little motivation to try to change out the autopilot. It's well matched to the plane and parts and knowledge to keep them working is still comparatively plentiful. Plus most new autopilots, including the Garmins, are unlikely to ever be certified for the PA-23. I think the STEC 55X analogue autopilot might be the only upgrade option today. I can have the entire IIIC overhauled at Autopilots Central for a fraction of what a new autopilot will cost to install.
 
Ryan F. said:
Partially true... according to my avionics installer, anyway. Magnetometer -> G5 -> GI275 works. Magnetometer -> GI275 -> G5 doesn't work.
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That’s interesting, didn’t know that.
 
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