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GRT HX - Procedure on moving map

RedRaider94

Active Member
Thought I would check with the GRT users out there. My HX screens are connected to my Garmin 430W and when I put a flight plan into the 430, it shows up perfectly on the moving map as a pink line.

Started my IFR training and was doing practice approaches. When I load and then activate the approach (GNAV OR ILS), the approach doesn’t show up on the map. Missed approach doesn’t either when I hit SUSP button on 430.

Is this normal or am I doing it wrong? I guess I assumed any white or pink lines on the 430 would always transfer to the GRT.

Thanks!
 
Your EFIS thinks you're still following the flight plan

On my Sport EX, I have to first "ARM" the approach. As I line up for intercept, I need to "EXECUTE" the approach on the EFIS. If your autopilot is engaged, these steps also capture the vertical element of the approach. Not sure if your EFIS performs identically, but I'd expect similar input is required. The approach mode (GPS or VLOC) is displayed on the EFIS - it's a good check to ensure that your NAV radio is properly set for the type of approach you're flying.
Terry, CFI
RV9A N323TP
 
One thing I did not do was Arm the approaches in the EFIS. I was hand flying all of the approach and the glide slope and localizer scales were working fine throughout the approach. I assumed that since the approach segments were showing in the 430, they would automatically populate on the maps.

Sounds like the GRT won't accept the approach segments unless that portion of the route is armed in the EFIS, which I was not doing. Very helpful and will do that next time to see if that fixes the problem.

Thanks!
 
One thing I did not do was Arm the approaches in the EFIS. I was hand flying all of the approach and the glide slope and localizer scales were working fine throughout the approach. I assumed that since the approach segments were showing in the 430, they would automatically populate on the maps.

Sounds like the GRT won't accept the approach segments unless that portion of the route is armed in the EFIS, which I was not doing. Very helpful and will do that next time to see if that fixes the problem.

Thanks!

Slightly different system, but the HX and HXr are similar in many ways ... I have an HXr/430W system. My steps are similar to Terry above, except that I do not have to "ARM" the approach in the HXr.

I have "flight plan set to external" so that I always load a flight plan and approaches via the 430W. When I "LOAD" only an approach, it appears/transfers to the HXr exactly as it displays in the 430W (ie, the flight plan with current routing, and then the loaded approach below the clearance limit). I then "ACTIVATE" the approach via the 430W, which now makes it part of the active route. My last step is to "EXECUTE" the approach in the HXr.

When I do not "EXECUTE" the approach in the HXr, the lateral deviation scale will appear, but the vertical deviation scales will not appear, and the autopilot will not follow the approach guidance.

If you haven't already, try viewing the FLT PLN on the EFIS before and after each input to the 430 to ensure it is transferring properly to the EFIS. Also ensure that your active NAV source in the EFIS is the 430, ie "GNAV" in my arrangement. Your naming convention may be different, but the active NAV source will appear in the FMA boxes above the airspeed tape.

As previously stated, the videos mentioned are a good source of information.
 
ARM Approach

Shawn - The reason you have to "arm" the approach in the GRT (and other EFIS's too) is because think about if you have the approach queued up in the 430 and the GRT, but you haven't heard those magic words from ATC "cleared for the approach". ATC says fly heading XXX. With the AP on, the GRT is in HEADING mode, and you're flying the assigned heading. You do NOT want to turn inbound on the approach if you haven't been cleared. Once you hear "cleared for the approach", that's when you arm the approach in the GRT, so now the GRT will intercept the inbound course and the approach will start.
 
Shawn - The reason you have to "arm" the approach in the GRT (and other EFIS's too) is because think about if you have the approach queued up in the 430 and the GRT, but you haven't heard those magic words from ATC "cleared for the approach". ATC says fly heading XXX. With the AP on, the GRT is in HEADING mode, and you're flying the assigned heading. You do NOT want to turn inbound on the approach if you haven't been cleared. Once you hear "cleared for the approach", that's when you arm the approach in the GRT, so now the GRT will intercept the inbound course and the approach will start.

THIS ^^^ is the good stuff. Learning by rote is one way to do it, but learning WHY the buttonology works in a particular way really helps the information stick in our brain!
 
Thanks Dave - that helps tremendously. Need to get you over to the hangar to walk me through the GRT for IFR flying when you get some free time! Sounds like I have a lot to learn about these boxes!
 
Slightly different system, but the HX and HXr are similar in many ways ... I have an HXr/430W system. My steps are similar to Terry above, except that I do not have to "ARM" the approach in the HXr.


When I do not "EXECUTE" the approach in the HXr, the lateral deviation scale will appear, but the vertical deviation scales will not appear, and the autopilot will not follow the approach guidance.

If you haven't already, try viewing the FLT PLN on the EFIS before and after each input to the 430 to ensure it is transferring properly to the EFIS. Also ensure that your active NAV source in the EFIS is the 430, ie "GNAV" in my arrangement. Your naming convention may be different, but the active NAV source will appear in the FMA boxes above the airspeed tape.

As previously stated, the videos mentioned are a good source of information.

I believe you have to ARM the approach to get the vertical guidance. You state that by not EXECUTING the approach on the HXr you don’t get the vertical guidance. Try ARMing VNAV next time and it will show in the scoreboard and you will get the vertical bars. GNAV also will switch to ENAV in the final segment. I’ve been using the HXr for many years and have never seen an EXECUTE softkey if I don’t activate the approach and have approach ARMED.
 
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