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GI275 and Aspen question


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Just had a GI275 installed as a standby ADI. My primary ADI/HSI is an Aspen. Garmin’s website says the GI275 is capable of receiving two VHF Nav sources and 2 GPS Nav sources in CDI and HSI mode and you can select the source you wish to display with a soft key. 
Website also says that my GNS 530W and my KX155 are compatible sources for the VHF Nav signal. Both sources currently display on the Aspen and the KX155 also displays on a KI209. I would like to remove the KI209 and display at least the KX155 data on the GI275. Ideally I would also like to display the 530 Nav data as well.

My avionics shop says I can’t have both the Aspen and GI275 display Nav data (VOR/LOC/GS). Does that make sense?

Any avionics expertise would be appreciated. 
Sorry I don’t have any panel-porn pics to share yet. Airplane is still in the shop. 

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Paul, great question.  I am doing something similar with a GTN driving a G500 primary display and wanting a SL30 and GI-275 as a secondary Nav and ADI backup.

Let me try answer this in a roundabout way.  If I had a secondary display like a Sandel SN3500, it could have two GPS's, Two ILS, ADF, and more.  And then with a flick of a switch I could turn the backup AHARS/display on.  It looks like the GI-275 can do all of this (pity no ADF for us in Canada).

Now the difficult part - I've seen some GI-275's installed as MFD's, and then you get all the pages (21 I think?).  You can hardwire a switch to instantly get to the backup ADI (and I think you will still have a CDI for navigation).  This seems to be what you are trying to achieve?  The GI-275 has an internal GPS with a simple 'direct to' navigation input.  One external GPS (your GNS530) is better, because then it will start displaying a flight plan.  I can see this being able to work in parallel with your Aspen as both displays are just showing the same flight plan.  If you had 2 external GPS's I can see this being a problem doing all the switching between 2 displays and 2 GPS's.

Now 2 Nav's and 2 displays is going to be a problem - which one is the 'master' to set the OBS?  If you had an all Garmin panel, I could see this working, they are good at integrating.  Aspen and Garmin, not so much.  Unless the OBS of the Aspen and GI-275 can be sync'd, I would say your shop is correct.

The next issue is configuration, once you start setting the GI-275 as ADI or HSI, you start losing some of the pages.  I am not familiar enough yet to know.  The question you need to ask, is once the 275 is set as backup Attitude Indicator, what pages are left?  And can you navigate off this?  Can you set the OBS?

I think the real objective is to have redundancy, and not to worry too much about displaying every nav/gps option with every display.  I want a GTN750 and G500 to be my primary navigation and display, coupled with the autopilot.  My SL30 and GI-275 is my backup (and monitoring) navigation, I think it's great that it also has an internal GOPS and a direct to feature and a backup AH.  I want to make sure that with everything else 'off' I can fly direct to a point and keep the right side up.  Then next 'must have' is to be able to fly at least a VOR/ILS approach.  With these, I don't care that I have to hand fly with no autopilot.  I've flown for more than 20 years behind a KFC200 autopilot, and never once wanted the AP to fly Nav2 (or now GPS2).

(I wrote this fairly quickly, so E&O excluded)

 

Aerodon

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Great details Don!

As time has passed... so have the versions of the install manuals of the big G devices...

Really important for what can be connected... as the lists have grown...

Also important for what can legally back up what... As this has changed a bit as well...

And what else is needed for proper back-up devices... like independent power sources... or batteries...

PP thoughts only, exercising my memory...

Best regards,

-a-

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Paul,

 

A second attempt at answering:

A KX155 has a composite output, which means that the conversion and OBS are done internally in the GI-275 (and probably the Aspen).  So if the KX155 can be legally connected to two displays in parallel, I can see this working.  I can see the GNS530 GPS navigation working on two displays.   And if the GNS530 has two Arinc ports (in and out), I can see this working on two displays too. 

So this issue is what Garmin allows once the GI-275 is configured in HSI/Backup mode, or maybe even MFD/Backup ADI mode.   And what Garmin says in the installation instructions.  

Interesting question.

 

Don

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I am having a very similar setup installed.  Here my setup....

Primary display is an Aspen PFD with a Garmin Gi-275 as the backup.  

Garmin GTN650 GPS/Nav/Com will be the primary Navigation and Comm with a Garmin GNC-355 as the backup GPS and Comm 2.  A Garmin GTX-345 will provide ADS-B traffic and FIS-B weather.

The above will feed the Aspen and GI-275 with GPS 1, GPS 2, NAV 1, Traffic & Weather 

Autopilot is driven by the Aspen. 

I'm still trying to decide what's going to be on all the displays and this may change over time.  I *think* initially I will set it up this way:

  • Aspen will have the FP course (obviously), terrain, weather and traffic (set only to show the immediate threats)
  • Aspen may also be in the Synthetic Vision mode, but I need to fly a while to see if that will always be on
  • Gi-275 will probably be in Traffic Mode for the bigger picture with an occasional switch as needed to the custom page that shows ETA, etc.  TBD on exactly what will be on that page.  (Also obviously available on the GTN, but the 275 will be in the primary scan to just turn the knob to see the info.)
  • GTN screen I'm still trying to decide on since I have the other screens, it may very well sit on the FP page on IFR flights for quick changes, not sure on VFR flights
  • GNC will be on the Map page as a cross reference to make sure all is good with the course compared to the GTN (still have to manually set the FP, but I hear rumors that eventually there will be a software upgrade to allow cross fill of the FP.  Apparently I'm not the only one that wanted a Backup GPS and Comm2, so they're having to rethink allowing communications with the GTN & GNC devices.  (GEE... REALLY... Very short sighted not to allow the obvious Backup GPS & Com choice for people that didn't want to buy two GTNs) 

In an earlier post someone mentioned setting two heading bugs.  Yes, the Aspen and  the 275 both have bugs, but I don't see any reason to have them both displaying the FP and setting both bugs.  The 275 cannot be connected to my AP, so if the Aspen fails, I'll be hand flying.  Guess some cross-over relays could be installed, but I'm not going that route.  But even if you did and the Aspen failed, it would not be an instant switch to the 275.  So you'd be hand flying for a few seconds to get the 275 in the right configuration, then you'd toss the switch.  And my AP I believe will default to wing leveler mode if it loosed input from the Aspen (note to self to confirm that now....)

Also, I asked Garmin if there was a button push or other fast switch option to get to the AI/FD screen.  When I asked they said no and said basically the fastest way is to just quickly turn the knob to get to the 1st page.  I did send in a Feature Request to consider adding a fast switch option, so maybe they've added it in the latest software.

 

 

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11 hours ago, PeteMc said:

 

Also, I asked Garmin if there was a button push or other fast switch option to get to the AI/FD screen.  When I asked they said no and said basically the fastest way is to just quickly turn the knob to get to the 1st page.  I did send in a Feature Request to consider adding a fast switch option, so maybe they've added it in the latest software.

 

 

You can install a toggle switch to instantly get to the ADI.  Or select from the menu.  Or it does it automatically when it detects a failure of main ADI.

 

Aerodon

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12 hours ago, Aerodon said:

Paul,

 

A second attempt at answering:

A KX155 has a composite output, which means that the conversion and OBS are done internally in the GI-275 (and probably the Aspen).  So if the KX155 can be legally connected to two displays in parallel, I can see this working.  I can see the GNS530 GPS navigation working on two displays.   And if the GNS530 has two Arinc ports (in and out), I can see this working on two displays too. 

So this issue is what Garmin allows once the GI-275 is configured in HSI/Backup mode, or maybe even MFD/Backup ADI mode.   And what Garmin says in the installation instructions.  

Interesting question.

 

Don

Thanks Don, (It's Mark BTW, not Paul)

My KX155 was already connected to the KI209 and the Aspen so I am pretty sure it should be capable of displaying on the GI if I remove the KI209. 

My original plan was to keep the KI209 on the logic that if the Aspen failed, I would need the GI275 as my ADI and I would not be able to view the CDI/GS indications. Then I learned that the main ADI display on the GI275 can also show CDI and GS indications so I thought, why not use them and get rid of the KI209? I am hoping that one of the avionics installers that frequent this forum and have installed GI275s could help answer this. Maybe @Jesse Saint or @Baker Avionics

The second, and bigger question to be resolved is whether I can still access the Map, HSI and other cool features of this device when it is configured as a Standby ADI. My shop initially told me that I could, which is why I agreed to this upgrade (more on that later), but now they are saying that it is "supposed to remain in Standby ADI mode". With multiple Garmin displays, there is a reversion switch included. In the Auto position it will switch the GI back to ADI mode if the primary ADI fails. If that doesn't work, you can select the switch to On and accomplish the same thing. My shop says the GI has no way to know if the Aspen has failed so the GI can't switch automatically. When I read the STC however, it is not clear that it must be locked in ADI mode, especially since it is only one twist of the control knob away at any time.

So what I need to determine is:

1) Is there a way to have the GI275 automatically switch to ADI mode if the Aspen fails?, and 

2) Is this required by the STC in order to be able to use the other features?

Cheers,

Mark

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I know the GI-275 can receive cross-feed from (some?) other Garmin devices.  That video I saw a while ago I believe said the full FP and heading bug for sure.

Do you know if it detect an Aspen failure? 

An industry standard failure code would be a great safety addition.  Then any device from any manufacturer that has multi display pages would instantly revert to the main ADI if the PFD failed.  There may only be a few options now, but who knows how many there will be in 5 years.

 

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11 hours ago, PeteMc said:
  • Aspen will have the FP course (obviously), terrain, weather and traffic (set only to show the immediate threats)
  • Aspen may also be in the Synthetic Vision mode, but I need to fly a while to see if that will always be on
  • Gi-275 will probably be in Traffic Mode for the bigger picture with an occasional switch as needed to the custom page that shows ETA, etc.  TBD on exactly what will be on that page.  (Also obviously available on the GTN, but the 275 will be in the primary scan to just turn the knob to see the info.)
  • GTN screen I'm still trying to decide on since I have the other screens, it may very well sit on the FP page on IFR flights for quick changes, not sure on VFR flights
  • GNC will be on the Map page as a cross reference to make sure all is good with the course compared to the GTN (still have to manually set the FP, but I hear rumors that eventually there will be a software upgrade to allow cross fill of the FP.  Apparently I'm not the only one that wanted a Backup GPS and Comm2, so they're having to rethink allowing communications with the GTN & GNC devices.  (GEE... REALLY... Very short sighted not to allow the obvious Backup GPS & Com choice for people that didn't want to buy two GTNs)

Hi Pete, 

Thanks for the reply. A very similar set up to mine other than the nicer and newer NavComs.

WRT your bullet points:

  • The Aspen is my primary map display but the GI275 Map also displays my FP from my 530W which I really like. It's better than the Aspen Map. Since you have a GTN and GNC, you probably wont need this.
  • Aspen Synthetic Vision has to be selected on for every flight. It always defaults back to the normal display on shutdown. Frankly I find the SV on the Aspen pretty "meh" due to the narrow FOV. It doesn't do much for my SA so I often forget to turn it on until halfway through the flight. The Safe Taxi mode of the GI Map display, on the other hand, is really useful for those times that I am looking up something else on the iPad like an FBO frequency and don't have the taxi chart up.
  • I went with a Lynx 9000D+ for traffic. It will not display on the GI275. But Active Traffic is way cool. Especially up here in Canada where few GA aircraft have ADSB.

Good luck with the installation.

Mark

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24 minutes ago, squeaky.stow said:

Thanks Don, (It's Mark BTW, not Paul)

My KX155 was already connected to the KI209 and the Aspen so I am pretty sure it should be capable of displaying on the GI if I remove the KI209. 

My original plan was to keep the KI209 on the logic that if the Aspen failed, I would need the GI275 as my ADI and I would not be able to view the CDI/GS indications. Then I learned that the main ADI display on the GI275 can also show CDI and GS indications so I thought, why not use them and get rid of the KI209? I am hoping that one of the avionics installers that frequent this forum and have installed GI275s could help answer this. Maybe @Jesse Saint or @Baker Avionics

The second, and bigger question to be resolved is whether I can still access the Map, HSI and other cool features of this device when it is configured as a Standby ADI. My shop initially told me that I could, which is why I agreed to this upgrade (more on that later), but now they are saying that it is "supposed to remain in Standby ADI mode". With multiple Garmin displays, there is a reversion switch included. In the Auto position it will switch the GI back to ADI mode if the primary ADI fails. If that doesn't work, you can select the switch to On and accomplish the same thing. My shop says the GI has no way to know if the Aspen has failed so the GI can't switch automatically. When I read the STC however, it is not clear that it must be locked in ADI mode, especially since it is only one twist of the control knob away at any time.

So what I need to determine is:

1) Is there a way to have the GI275 automatically switch to ADI mode if the Aspen fails?, and 

2) Is this required by the STC in order to be able to use the other features?

Cheers,

Mark

Mi Mark 

I'm trying to do the same thing as you, so will do the research needed to get to the bottom of this.  It's a good point, does the 'standby ADI display enough information for a legal second navigation display.  After all, thats the main objective.

It seems that to get full GPS1, GPS2, Nav1, Nav2 configuration you would need pretty much the latest generation of navigators like GTN / GNC series.

It seems technically possible to connect both your GNS530 and KX155 to both displays.  (The KX155 manual shows multiple indicators on the composite output).  But it is a little tedious installing parallel wiring for the composite output a GS indications, and ILS selected etc.  I would not bother trying to get KX155 Nav onto the Aspen.  But I would try get both navigators onto the GI-275.

1) I doubt there is a way for the GI-275 to identify an aspen failure.  Might be an idea to install the switch for instant 'pullup' of the ADI.

2) This is the key, and I have not found documentation yet.  I do know that if you set-up the GI-275 as a MFD, you get everything.  If you setup as a primary ADI, you get far fewer pages.  So why not think the physical installation through to achieve the most functionality that you can reasonably achieve.  Then set the instrument as HSI / Standby ADI and see what's left?

Don

 

(sorry about the wrong name, I was thinking of GSX,)

 

 

 

 

 

 

 

 

 

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Right now mine is configured in Standby ADI/MFD mode. This includes pages for ADI, CDI, HSI, HSI/Map, Traffic, Terrain, Map, and an MFD Data page that has 7 fields of data that are user-programmed. All that extra stuff is what sold me on the GI275 over cheaper alternatives. I sure don’t want to lose that. 
I had originally planned to install a used Sandia Quattro that I bought here on MS as my Standby ADI but we all know that story.....

BTW, anybody want to buy a Sandia Quattro? ;-)

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Update. Got my plane back today with all of the little snags from the installation fixed.

The GI275 can display Nav/Loc data from an analog source like the KX155, but only if it is configured as an HSI or CDI (or MFD). As a Standby ADI it can only display digital CDI information from my 530. So I had to keep my KI209 for redundancy.

The good news is that I can still have Traffic, Terrain, Map and MFD data pages with the Standby ADI configuration. 

I was so busy playing with all the new stuff that I forgot to take pictures. MTF.

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If the Gi275 is paired with a G500TXI, it communicates with It via HSDB. , and it can be used as an MFD. If the G500TXI fails, then it reverts the go 275 back to primary  ADI. If you don’t have that display, or another GI275 to do the same thing, then it has to be locked as a standby ADI all the time

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  • 2 months later...
On 1/9/2021 at 1:55 PM, squeaky.stow said:

While I think of it, @Rmag you have some relevant experience with GI275 installations. Any comments?

Sorry, got to this thread a few months late.  The GI 275 Part 23 AML STC Installation Manual dictates the configuration of the GI 275 when used as a standby instrument.

You can see except for dual GI 275’s and a G500/G600 TXi w/GSU 75 or GRS 79 & GDC 72 or internal ADAHRS when used as a standby instrument the GI 275 must be configured as an ADI Only, which means all of the other pages are not available.  It specifically states “Third Party” (which the Aspen is) needs to have the GI 275 in ADI only mode.

Although compliance with the STC is the only reason you really need, think about the practical reasons why... 

@jetdriven touched on a very practical reason why you want your backup configured as an ADI only with an Aspen.  With a dual GI 275 or a G500 TXi connected via the HSDB, there is continual electronic cross checking of the ADAHRS.  If there is a miscompare or failure of a primary ADARHS when the standby is on a non-ADI page, the unit immediately and automatically switches to the ADI only configuration with a flag telling you what has failed on your primary.

You have none of that automation backing up an Aspen.  It is up to you as a pilot to manually compare flight data between the two instruments and recognize any errors.  Also ask yourself the question, “What is required to backup an Aspen?”  The answer is your attitude, altitude, and airspeed instruments.  If you have the GI 275 off on some Traffic, Terrain, Map and MFD page do you have the backup instruments the Aspen requires in the pilot’s view?  No.  Do you have automatic reversionary to ADI if something fails on the Aspen? No.  Are you in compliance with the GI 275 STC?  No.

The good news is that it is a very simple configuration change that takes one minute to change to fix this.

E4F3F109-CE14-4DA9-93B2-D2CAB537438C.jpeg

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4 hours ago, J0nathan225 said:

Looking at this. It seems you got away with not needing to keep steam A/S & Alt.  That’s what I’m trying to do va repairing my steam Alt.  Is that a MAX Aspen? 

My Aspen is not a MAX. The GI275 can be used to replace all backup steam instruments but as stated by @Rmagit is supposed to be used only as an ADI if paired with an Aspen as there is no automatic reversion. 

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