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Vertical/Horizontal Guidance

MED

Well Known Member
I am probably overlooking something, but when I hand-fly a practice approach (ILS or RNAV), using dual cue guidance on the G3X and the G5, I don’t get left/right, up/down guidance like I would in my airplane with a Garmin 430 and a conventional nav head. What am I missing? :confused:
 
Check the wiring and config

Check the wire drawings and see if the 430 passes the info/data to the G3X and if the configuration settings are set for that kind of matchup. It might be different?
 
Check the wire drawings and see if the 430 passes the info/data to the G3X and if the configuration settings are set for that kind of matchup. It might be different?

I guess I should have said in my message that I have a Garmin 650 gps feeding the G3X in the RV. I am comparing it to a different airplane with a Garmin 430 gps feeding a conventional nav head, like we are all familiar with for following a VOR or ILS. I am hoping there is a way for the G3X dual cue display to behave like a conventional nav head. Sorry for the confusion.
 
I am probably overlooking something, but when I hand-fly a practice approach (ILS or RNAV), using dual cue guidance on the G3X and the G5, I don’t get left/right, up/down guidance like I would in my airplane with a Garmin 430 and a conventional nav head. What am I missing? :confused:

Did you arm the APP, the FD is basically a function of the AP just without the servos engaged (AP off).
(I'm assuming it will fly the approach with the AP engaged).
 
Did you arm the APP, the FD is basically a function of the AP just without the servos engaged (AP off).
(I'm assuming it will fly the approach with the AP engaged).

I did not arm the approach, because I was trying to hand-fly and did not think I needed to use the autopilot at all. It does work with the autopilot flying. That must be the problem. Duh. Thanks. :eek:
 
Did you arm the APP, the FD is basically a function of the AP just without the servos engaged (AP off).
(I'm assuming it will fly the approach with the AP engaged).

That's curious. Not having the flight director is one thing, but if you have the LOC/GS tuned and the you have switched from GPS to LOK, shouldn't you see the deviations anyway (without the flight director)?

I'll be interested in how the OP's refly goes. Were you sure you were in LOC on the navigator and not GPS?
 
That's curious. Not having the flight director is one thing, but if you have the LOC/GS tuned and the you have switched from GPS to LOK, shouldn't you see the deviations anyway (without the flight director)?

I'll be interested in how the OP's refly goes. Were you sure you were in LOC on the navigator and not GPS?

The Duel cue/V bar display is from the FD though.
 
It could be confusing in this discussion to differentiate between 'Activating Approach (GTN)' and 'Arming Approach (Autopilot)'.

You'll always need to activate the approach on the IFR Navigator. If you want the VBar or Dual Cue (Flight Director), that is a function of the autopilot system. You need the Flight Director (FD) activated, along with Approach Mode (APR) armed. This is possible without having the autopilot servos engaged.

Either way with an Activated Approach (GTN/GNS), you'll be receiving vertical and lateral guidance, its just a matter if you have the Flight Director on or off, and if you have it queued to follow the glide path (APR armed).
 
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It could be confusing in this discussion to differentiate between 'Activating Approach (GTN)' and 'Arming Approach (Autopilot)'.

You'll always need to activate the approach on the IFR Navigator. If you want the VBar or Dual Cue (Flight Director), that is a function of the autopilot system. You just need the Flight Director (FD) activated, which is possible without having the autopilot engaged or Approach Mode (APR) armed.

Either way with an Activated Approach (GTN/GNS), you'll be receiving vertical and lateral guidance, its just a matter if you have the Flight Director on or off.

I had the flight director on and activated the approach in the 650, but I did not activate “apr” on the autopilot, because I was hand-flying and did not think I needed to tell the autopilot to activate. Are you saying it should have worked the way I did it? :confused:
 
One thing that messed me up when I first started flying with the G3X/GTN was forgetting to engage NAV mode when I was hand flying.

My buddy Matt taught me to always monitor the flight director “scoreboard” even while hand flying. Basically, using the FD and autopilot as if the AP was doing the flying even when hand flying.
 
I had the flight director on and activated the approach in the 650, but I did not activate “apr” on the autopilot, because I was hand-flying and did not think I needed to tell the autopilot to activate. Are you saying it should have worked the way I did it? :confused:

Hi - sorry I re-read my post and have corrected it. You do still need to arm Approach Mode (APR) even if hand flying. This queues the Flight Director to lock onto the glide path and follow it. This action will annunciate on the AFCS panel.

The cues will follow any mode activated for the Flight Director, even if you don't have the autopilot servos engaged (AP). So you still need to command the FD to follow the glide path (APR), from the external navigation source. If you don't do this - the FD will just be in pitch/roll mode (straight ahead), as indicated on the AFCS panel.

Think of it this way - its not an autopilot controller, its a flight director controller. Engaging the servos is what makes the autopilot follow the Flight Director that you're commanding with the buttons. You just wouldn't engage the servos to follow the Flight Director since you're hand flying in this case.

Sorry for the confusion...... Very capable systems that take a little work through to get the proper buttonology for each feature.
 
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Garmin

Would suggest that anytime you touch or change something check the scoreboard/status bar at the top of the PFD to ensure what you really want is active or armed. Sophisticated flight guidance systems make some things easier, but add to the workload by requiring extra monitoring.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Thanks for the follow-up, Brad. I will try again with autopilot approach activated as you and Walt have described. I am still new to the capabilities and required settings of both the autopilot and the G3X. Much different from my previous airplanes, and I am probably a little slower on the uptake, too. ;)
 
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