GPSS help

[bcg]

My installation manual is 190-01112-12 Rev. A and I could not find the limitation you have in your manual version.  I do have a separate CDI.  Here is a pic of the panel
I am wondering if I am confusing VLOC and VOR from NAV radio

What is that CDI connected to?

The early G5s only had the ability to connect to a single navigator, period. If you've got one of those, the limitation won't be there because connecting to 2 navigators was impossible at the time.

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[Wingover]

So basically I can't have the AP to follow a GPS route with my setup?  The Garmin 255A NAV is connected to the G5 as the Garmin 175

I am not sure why the AP can follow the needle of the VLOC but not the needle of the GPS

[OR75]

4 minutes ago, Wingover said:

So basically I can't have the AP to follow a GPS route with my setup?  The Garmin 255A NAV is connected to the G5 as the Garmin 175

I am not sure why the AP can follow the needle of the VLOC but not the needle of the GPS

if you are connecting 2 different navigators to 1 G5 , you must have some kind of annunciation somewhere (or the install is .... hmmmm ... should be looked at)

in the case of a GNS or GTN , the annunciation is in the navigator. 

honestly , at this stage , the best you could do would be to find a nearby pilot or instructor who is familiar with this kind of setup and who can sit in the plane and turn some knobs and press some buttons

 

[bcg]

23 minutes ago, Wingover said:

So basically I can't have the AP to follow a GPS route with my setup?  The Garmin 255A NAV is connected to the G5 as the Garmin 175

I am not sure why the AP can follow the needle of the VLOC but not the needle of the GPS

Maybe, it depends.

Here's how it would work.  175 connected to GAD29B/D vai AIRNC 429 and the G5 via RS 232. GAD29B/D connected to G5 via AIRNC 429.  NAV radio connected to the standalone CDI.  Then the AP will be driven by the GPS and you'll have GPSS routing and would not be able to track a VOR or LOC with the AP. 

What is the CDI you have installed connected to right now?  Is it giving RNAV approach guidance?  Do you have both a green and magenta arrow on the G5 HSI or only green?  If I knew this, I could better answer the question.

[Wingover]

18 minutes ago, bcg said:

Maybe, it depends.

Here's how it would work.  175 connected to GAD29B/D vai AIRNC 429 and the G5 via RS 232. GAD29B/D connected to G5 via AIRNC 429.  NAV radio connected to the standalone CDI.  Then the AP will be driven by the GPS and you'll have GPSS routing and would not be able to track a VOR or LOC with the AP. 

What is the CDI you have installed connected to right now?  Is it giving RNAV approach guidance?  Do you have both a green and magenta arrow on the G5 HSI or only green?  If I knew this, I could better answer the question.

It seems the the standalone CDI is connected to the NAV1/NAV2 but will verify tomorrow. RNAV approach is on the G5 in VLOC mode as green needle and glide slop. If I click the large button on the G5 and select GPS, I have a magenta needle. We tracked a localizer and the AP was flying the course and glide slop.

[bcg]

1 hour ago, Wingover said:

It seems the the standalone CDI is connected to the NAV1/NAV2 but will verify tomorrow. RNAV approach is on the G5 in VLOC mode as green needle and glide slop. If I click the large button on the G5 and select GPS, I have a magenta needle. We tracked a localizer and the AP was flying the course and glide slop.

If you have both green and magenta needles, then someone connected 2 nav sources to that G5.  I'm going to guess that the software got updated at some point (there should be a log book entry for that) and either at the same time or later, the GPS 175 was installed and connected to the G5, contrary to the instructions.  When you update the software, you need to install according the manual that's valid for that software so the Rev A manual is superseded by the software upgrade to whatever revision of the manual corresponds with the software installed.

You're in Portugal?  I don't know the rules there however, in the US, your installation isn't legal since it doesn't comply with the STC.  It's not going to crash the airplane but, it's technically not airworthy in this configuration.  I missed that you had 2 NAV radios earlier, with that clarification, your panel should consist of the G5 HSI and 2 additional CDIs so that each NAV source has it's own instrument. 

Here is what I would suggest doing to get your system working with the most utility.  I would remove the NAV radio that is currently connected to the G5, make sure the GPS 175, GAD29, G5 are all wired correctly, reconfigure the software for that setup and put in another CDI for the NAV radio. 

Alternatively, you could leave both nav sources on the G5, disconnect the AP from the G5 and use the NAV radio that's currently going to the stand alone CDI to drive the AP.  This would give you the same functionality you have currently in a way that complies with the STC.  You can have 2 nav sources on the G5 if it's either connected to a Garmin AP or not connected to a non-Garmin AP.

This isn't really a DIY job unless you've got Portugal's equivalent of a friendly A&P/IA to look over your shoulder and sign off on the work.

The one thing that I'm confused by though, is that you're saying the GPS RNAV approach shows up on the G5 in a green needle.  This should not be the case, all GPS guidance should be magenta so, if that is indeed what's happening, this definitely needs to be looked at by someone qualified because something is definitely wrong.  In the case that GPS guidance is truly showing up in green, disregard the rest of what I said and take it to an avionics shop for proper troubleshooting, it's likely going to need to be pretty in depth to figure this out.  Definitely more than we can do over the Internet.

[Wingover]

17 minutes ago, bcg said:

If you have both green and magenta needles, then someone connected 2 nav sources to that G5.  I'm going to guess that the software got updated at some point (there should be a log book entry for that) and either at the same time or later, the GPS 175 was installed and connected to the G5, contrary to the instructions.  When you update the software, you need to install according the manual that's valid for that software so the Rev A manual is superseded by the software upgrade to whatever revision of the manual corresponds with the software installed.

You're in Portugal?  I don't know the rules there however, in the US, your installation isn't legal since it doesn't comply with the STC.  It's not going to crash the airplane but, it's technically not airworthy in this configuration.  I missed that you had 2 NAV radios earlier, with that clarification, your panel should consist of the G5 HSI and 2 additional CDIs so that each NAV source has it's own instrument. 

Here is what I would suggest doing to get your system working with the most utility.  I would remove the NAV radio that is currently connected to the G5, make sure the GPS 175, GAD29, G5 are all wired correctly, reconfigure the software for that setup and put in another CDI for the NAV radio. 

Alternatively, you could leave both nav sources on the G5, disconnect the AP from the G5 and use the NAV radio that's currently going to the stand alone CDI to drive the AP.  This would give you the same functionality you have currently in a way that complies with the STC.  You can have 2 nav sources on the G5 if it's either connected to a Garmin AP or not connected to a non-Garmin AP.

This isn't really a DIY job unless you've got Portugal's equivalent of a friendly A&P/IA to look over your shoulder and sign off on the work.

The one thing that I'm confused by though, is that you're saying the GPS RNAV approach shows up on the G5 in a green needle.  This should not be the case, all GPS guidance should be magenta so, if that is indeed what's happening, this definitely needs to be looked at by someone qualified because something is definitely wrong.  In the case that GPS guidance is truly showing up in green, disregard the rest of what I said and take it to an avionics shop for proper troubleshooting, it's likely going to need to be pretty in depth to figure this out.  Definitely more than we can do over the Internet.

The installation was done "by the book"  the G5 software version is 8.3 and is all documented in the book.  The GPS175 was just installed at the shop.  They are looking into it right now but was hoping to understand what's happening.  I am in Portugal, yes.

Maybe I wasn't clear regarding the approach.  It is taking the VLOC (in green) from the NAV (as ILS) not GPS.

[OR75]

if you look at the manual, there is no provision to get GPS position and navigation from one source and a VOR navigation from another source. 

The source has to be a navigator like a GNS or a GTN because those include annunciation and the G5 knows where it is getting its navigation order from.

In your case, since your installation was done by the book, i am suspecting your G5 is only getting a GPS position from the GPS175 (but not navigation via the GAD29B)       

[bcg]

The installation was done "by the book"  the G5 software version is 8.3 and is all documented in the book.  The GPS175 was just installed at the shop.  They are looking into it right now but was hoping to understand what's happening.  I am in Portugal, yes.
Maybe I wasn't clear regarding the approach.  It is taking the VLOC (in green) from the NAV (as ILS) not GPS.

Respectfully, if you have both green and magenta needles and your G5 is driving a non-Garmin AP, your installation isn't by the book.

I'm glad you have someone looking at it, when you get it back you should have either a green or magenta needle only, not both. I'd want magenta so I could get GPSS steering and RNAV approaches via the AP. Look at pages 23, 179 and 154-157 in this doc, your answers are there.
https://static.garmin.com/pumac/190-01112-10_28.pdf.

I didn't like the answer when I did mine either, had I known going into it I would probably have gotten a GTN650 instead of the 175 and SL30, it wouldn't have been that much more. Unfortunately, I figured this out after I already had everything in hand and was into the install so, I made the best of it.

Good luck, I hope they get it worked out for you.

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