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GRT Horizon and Garmin 175 GPS?

macflyer

Active Member
Hi,
Is anyone utilizing a GRT EFIS and the Garmin 175 GPS? I was wondering about doing an LPV approach with these hooked to an ARINC. Any thoughts on this combo and actual ease of flying a GPS LPV approach with them.
Thanks!
 
I believe you’ll need an ARINC interface between the Garmin 175 and your GRT EFIS. However flying an LPV approach is just like flying an ILS. Just couple your autopilot and monitor until DA. Or follow the command bars/needles of your GRT. Easy!

Wish I had a Garmin 355 installed (175 w comm). Then I too could fly LPVs. But that upgrade for me is still a couple of years away.
 
I am trying to do the same thing: GNC-355 (same GPS as 175) to GRT Sport EX. I am completely confused as to how to connect the ARNIC module to the EFIS, I am beginning to think this is not possible with the Sport EX, The GRT interface notes do not mention the EX, only the HX. Does anyone know?
 
I have 2 GRT Sports and a 175. Not flying yet but everything works together nicely. I do have the GRT ARINC, which you’ll need or they won’t play together.
 
Yes, people are flying the grt efis-Garmin 175 combo.
If your efis does not have arinc ports you will need to buy grt’s add-on arinc box.
There are recommendations on ports, formats, etc, found in the grt forum. Search <175> to find them.
 
HXr & 175

I am using the HXr and 175. Works extremely well together. Let me know any specific questions you have and I will be happy to answer.
 
I am using the HXr and 175. Works extremely well together. Let me know any specific questions you have and I will be happy to answer.

I was thinking about doing this, as well. I believe that the HXr does not need an additional ARINC that it is already built in.
 
I am currently in the process of adding a Garmin GPS 175 to my GRT Sport EX with auto pilot. Hope to have it installed in the next week. You DO need the GRT ARINC-429. Make sure you have enough serial ports on your Sport EX. The ARINC uses a serial port (both in and out) on the EFIS plus it is desirable to have the Garmin 175 Rs232 connection go directly to the EFIS although it sounds like it is possible to use the ARINC for that purpose. I needed to add the extra serial port option because i did not have enough serial ports. The others were being used by my Echo UAT/Safefly ADSB out and in plus my auto pilot.

The settings for the Sport EX EFIS and the Garmin 175 have been posted on the forum and also mentioned on this particular thread. Jeff had GRT has been most helpful. My overall experience with GRT has been very good.

Good Luck. I will post my results after I get things installed. I have a little issue with "depth" for the mounting but believe I will be able to overcome it.
Keith
 
Just to clarify: the new grt 10.1 efis units do not have a built in ARINC port (older HXr and Hx efis units do have arinc ports), so you need their external arinc box. The external arinc box communicates with the efis by using an rs232 port. But, the arinc box also includes an rs232 port, so you don’t lose any. However, the rs232 port on the arinc adaptor is limited to 19k baud rate.
As always, it’s important to see if you have enough rs232 ports, considering baud rates needed, etc., for all your needs.
 
OK, here is my situation. I am currently flying with the GRT EX and TruTrak autopilot using a GRT ARINC 429 module. The ARINC module only has one 429 out A and one 429 out B. Both of these are connected to the Trutrak autopilot as required in the autopilot manual. This is all working fine giving me vertical autopilot capability with the GRT EX.
Now I want to add the GTN 355 to this mix. seems like I need to sent ARINC out signals to the GTN, but they are already being used by the autopilot. Have not been able to sort this out.
Am I going t need to add switches to select where the ARNIC connections go?
 
No switches needed. One ARINC-in pair can only receive signals from one ARINC-out A/B pair, otherwise there is confusion. But one ARINC-out A/B pair can go to multiple ARINC-in ports.
So: splice 2 new wires, one "A", one "B", into the existing arinc-out lines, and send them to the new ARINC-in ports.
 
Installation Manual

Looking at adding the 175 into RV8 with GRT Sport. Would like to review the 175 install manual to make sure it is a project I can tackle. Does anyone have the install manual they would be willing to share?
 
Flew today and my GRT Sport EX and Garmin GPS 175 seemed to "play well together". I had it coupled to my GRT autopilot and it flew a course reversal, an LPV approach plus missed approach and a hold. Pretty intuitive unit but I still need to practice more and get everything figured out before I fly in IMC. Today was a little too cold to spend much time practicing.

Attached is a picture. I had to move my EIS to below my GRT PFD and then mounted the Garmin top center. Still need to cover the larger hole above the Garmin unit and touch up some areas on the panel from previous avionics moves.

Keith
 

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