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GRT HXr autopilot and the GPS approach: Need button-pushing help

Arlen

Well Known Member
OK. So I'm learning the systems and this wonderful GRT HXr more and more each time I fly.

I'm trying to set it up to do a fully-coupled GPS/RNAV WAAS approach, but I can't get it to do the vertical/glideslope part....it stays at the altitude that it was holding prior to hitting the approach fix while it's tracking the GPS COURSE perfectly.

I'm selecting the approach in the GNS430W and activating it. The autopilot is ON, and I'm using the HDG bug to turn the assigned vectors toward the fix on the approach at the assigned (A/P-held) altitude. I hit Direct To-Ent-Ent for the assigned approach fix in the 430W...

Somebody please walk me though it from there.

TIA
 
Arlen, I installed the HXr in my RV-10 last spring. I would be happy to go over button pushing with you any time at your airplane or mine. I need to be sitting in front of the EFIS to do it, because I cannot remember button names and sequences sitting here at my computer.
 
Arlen, I installed the HXr in my RV-10 last spring. I would be happy to go over button pushing with you any time at your airplane or mine. I need to be sitting in front of the EFIS to do it, because I cannot remember button names and sequences sitting here at my computer.

David,
That's great! Thanks for "volunteering"

I'm at Massey, Hangar # 6.

Any chance you're available sometime tomorrow, or maybe Monday after work 5 o'clockish?

my cell
386- three one 4 - nine 8 4 four
 
As Dave said, go see him. It is hard to do this without sitting in front of the equipment. That being said....
I think pushing the direct to (iaf) is a mistake. That will delete the 430 flight plan and replace it with direct iaf. Push the flight plan button, highlight the iaf (which is there because you already loaded and activated the approach), then push direct. This will leave the whole flight plan intact.
After this, don't forget to go to the HXr autopilot menu and highlight GPSV arm. You do not have to wait until you are on the final approach course. Depending on the option you set up in the software controls, a button may appear asking you to activate the approach mode.

I always remind people that autopilots are great, but they require twice as much training time: first to be able to fly without it, and then to be able to fly with it.
 
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I always remind people that autopilots are great, but they require twice as much training time: first to be able to fly without it, and then to be able to fly with it.

Definitely, Bob. I spent the first 8 hours of flying the -6 without turning the autopilot on. Now, I'm in the learn-the-autopilot mode. When I fly, I typically fly some by hand and some by A/P. I'll use the A/P for approaches once I get pretty confident in my understanding of it.

I've flown a few apps by hand in the -6 now..
 
I had to go back through my emails to remember the exact behavior.. this was with earlier version of software, so not sure if they changed the behavior with current version.. Anyways, arming GPSV prior to HILPT would have switched the EFIS to ENAV and you could not switch it to GNAV any more... that would cause the AP to not execute HILPT (as it needed to be in GNAV mode to follow the hold). Therefore proper procedure (at that time) was to arm GPSV when you're inbound and completed HILPT.

Pls verify how it behaves now in current software version.. there may have been some changes in behavior :)
 
. Keep Lat AP in "GNAV" mode.

http://www.grtavionics.com/Using Autopilot - Flight Director.pdf

Page 1 shows those menu options.

While inbound for the approach, have LNAV set to GNAV (so it will do turn anticipation). Once on final, the HXr will automatically switch to ENAV. If you push "missed" it will go back to GNAV.
I have the newest software and that's how mine works. Arm the approach anytime, it switches when on final.

Edit: I should go check wrt the holding pattern behavior, I fly so few, you may be right there. It must be in GNAV to do the holding pattern, as you say.
 
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...a big Thank You to David Maib for taking the time today to sit with me in his beautiful -10 to talk Hxr and 430W....and other RV goodness.

:D

.
 
When to push "GPSV ARM"

While inbound for the approach, have LNAV set to GNAV (so it will do turn anticipation). Once on final, the HXr will automatically switch to ENAV. If you push "missed" it will go back to GNAV.
I have the newest software and that's how mine works. Arm the approach anytime, it switches when on final.

Edit: I should go check wrt the holding pattern behavior, I fly so few, you may be right there. It must be in GNAV to do the holding pattern, as you say.

Okay, I went out and checked. (Why is this easier when flying than when typing?)
My setup: HX with V6 software (latest), G420W, Trio Pro with GPSS/GPSV, but I suspect HXr and HS and other GPSS autopilots will all be the same.

Starting Point: G420W has an LPV gps approach loaded and activated. GRT has the 420 gps selected as the nav source.
Case 1: If using the gps to navigate along a NoPT route to final, set GRT to GNAV; Set "GPSV Arm" anytime, before or after final course intercept. GRT goes from GNAV to ENAV at intercept if set before, otherwise when you select ARM. (Set it before glide slope intercept or the autopilot will dive the airplane to try to catch it!)
Case 2: If being vectored to final, set GRT autopilot control to "Heading". Use heading bug to set in vectors. Select "GPSV ARM" PRIOR to final course intercept. GRT will automatically go from Heading to Enav at intercept
Case 3: If using gps to navigate to a holding pattern course reversal: Select "GNAV" on GRT. Do NOT select "GPSV ARM" until inbound for the approach. If you need more than the course reversal, e.g., you need to actually hold, do not select ARM until inbound the last time (and you will need to push OBS on the 420W to keep it from sequencing during the hold).
 
Okay, I went out and checked. (Why is this easier when flying than when typing?)
My setup: HX with V6 software (latest), G420W, Trio Pro with GPSS/GPSV, but I suspect HXr and HS and other GPSS autopilots will all be the same.

Starting Point: G420W has an LPV gps approach loaded and activated. GRT has the 420 gps selected as the nav source.
Case 1: If using the gps to navigate along a NoPT route to final, set GRT to GNAV; Set "GPSV Arm" anytime, before or after final course intercept. GRT goes from GNAV to ENAV at intercept if set before, otherwise when you select ARM. (Set it before glide slope intercept or the autopilot will dive the airplane to try to catch it!)
Case 2: If being vectored to final, set GRT autopilot control to "Heading". Use heading bug to set in vectors. Select "GPSV ARM" PRIOR to final course intercept. GRT will automatically go from Heading to Enav at intercept
Case 3: If using gps to navigate to a holding pattern course reversal: Select "GNAV" on GRT. Do NOT select "GPSV ARM" until inbound for the approach. If you need more than the course reversal, e.g., you need to actually hold, do not select ARM until inbound the last time (and you will need to push OBS on the 420W to keep it from sequencing during the hold).

Bob,
You are correct on all three scenarios and the case #2 will also apply for ILS approaches which are far more likely to be vectored than a typical GPS approach. This method makes flying ILS approach easier than a-walk-in-the-park. What I have learned, NOT to arm it until you have been cleared for the approach. There has been times that I have vectored cross the localizer and if you arm it too soon, the system will sees that an intercept and will try to follow the course.

On other notes, thanks for sharing that the new SW version has been released. Do you know what or how much would be the subscription for the IFR charts and plates?
Looks like one of the new features in the new version is ?Add georeferenced plates, diagrams, sectionals, enroute low, and enroute high charts?
 
Execute

On the HXr I always ARM all the modes well before flying the approach and then push EXECUTE once cleared for the approach and inside the normal intercept parameters. This way, I'm briefed and setup early on the terminal phase and usually before top of descent.

Are you guys using the EXECUTE function?
 
On the HXr I always ARM all the modes well before flying the approach and then push EXECUTE once cleared for the approach and inside the normal intercept parameters. This way, I'm briefed and setup early on the terminal phase and usually before top of descent.

Are you guys using the EXECUTE function?

That sounds like the way to go. Since this is a relatively new feature I had been pushing it as soon as I armed, out of fear I would forget! Not sure how, with it right in front of you. Latest software lets you turn it on or off.

Charts will come from Seattle Avionics. i can only guess that they will set the price.
 
Bob, thanks for testing it out.. I guess the behavior is still the same.. I first remember running into it 2+ years ago and have reported it to GRT back then, but I guess no changes have been made... Technically that's fine, but just something to be aware of (so it doesnt' catch you by surprise when you least need surprises :) )
 
I think I'll adopt Jerry's method of setting it up early, but holding off of the execute button until just before intercept.
 
I think I'll adopt Jerry's method of setting it up early, but holding off of the execute button until just before intercept.

This is how I have been doing it since the change was made. It is really great to stay ahead of the game and only one push instead of going thru the menu.
 
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