Using TOGA button to initiate GTN missed approach

[PT20J]

The GTN navigators can be configured with an external button which Garmin calls "Remote Go Around" and describes as follows: 

Missed Approach: This momentary discrete input may be used to activate the missed approach prior to the missed approach waypoint (MAWP); similarly this discrete may be used to activate the missed approach following the MAWP popup.

The G3X Experimental installation manual shows a DPST TOGA button with one pole used to initiate Go Around in the autopilot and the other to signal the GTN to sequence the missed approach. Since the GTN manual does not stipulate what switch is used to activate the remote go around, this would seem to be a legitimate and useful installation in a certificated system.

I kind of like the idea of pressing one button to to initiate the missed approach on both the flight director and the GTN.

Has anyone had their GFC 500 and GTN set up this way and if so, any thoughts on it?

Skip

[Ragsf15e]

Skip, what do you think it means to “activate the missed prior to the mawp?”  You’ll still need to fly to the mawp, so what is activated, just the climb?  But I wouldn’t think the GTN would care about the climb, maybe just the G5 or G3x controlling the AP/Flight Director.

Additionally, the button seems similar to the g1000 toga which both initiates the climb and sequences to the first point on the missed.

Edited June 25, 2021 by Ragsf15e

[PT20J]

7 hours ago, Ragsf15e said:

Additionally, the button seems similar to the g1000 toga which both initiates the climb and sequences to the first point on the missed.

Thats what I believe it does based on the descriotion.

[201Mooniac]

I have it hooked up in my plane and when I press the TOGA button, the GFC-500 goes to GA mode (pitch up, wings level) and the GTN removes the screen you need to tap to sequence to the missed approach segment.  It works well and stops you from having to look over to the navigator.  I would recommend it but if you didn't have it I'm sure you'd get used to the one extra button push quickly.  For me it is more about not having to look over to the navigator to select the correct spot on the screen for the button than actually removing one button press.

[PT20J]

1 hour ago, 201Mooniac said:

I have it hooked up in my plane and when I press the TOGA button, the GFC-500 goes to GA mode (pitch up, wings level) and the GTN removes the screen you need to tap to sequence to the missed approach segment.  It works well and stops you from having to look over to the navigator.  I would recommend it but if you didn't have it I'm sure you'd get used to the one extra button push quickly.  For me it is more about not having to look over to the navigator to select the correct spot on the screen for the button than actually removing one button press.

Thanks. That was my thought also. But since this capability is kind of buried in the installation documentation for the GTN, I wonder how many get installed this way. Or maybe all the installers know about it and it’s common.

Skip

[Stanton R]

There is a hookup for the GTN shown in the GFC 500 installation manual.

[Warren]

Here is the hookup referenced above.

It's not buried but listed in the main drawings for the interconnects.

[PT20J]

13 hours ago, Warren said:

It's not buried but listed in the main drawings for the interconnects.

It's "buried" in that it is in the installation manuals which are only available to Garmin dealers. I did find a description in the G3X Pilot's Guide but not the G5. But the G3X description is cryptic because it refers to it being "properly configured." Since Garmin generally uses the term "configuration" to mean items that are set up in the software in "Configuration Mode", it's not clear from the documentation available to the pilot that this requires the addition of a hardware connection. I found a GFC 500 installation manual rev 10 on the web. Yours must be a later revision because mine does not show the TOGA connection to the GTN.

Skip

 

[Warren]

Fair point that only a dealer has access to the installation kit - but, I assumed a dealer would be involved in the install.

I would expect that anyone currently installing a GFC 500 with a GTN product would be using the current Installation Manual and installing the connection to the GTN for the Go Around.

 

Probably good to mention to the dealer that you want to ensure it is wired this way for the install.

[MisfitSELF]

TOGA button is described in the GI275 Pilots Manual in the autopilot section -- page 197 for the electronic copy I'm looking at now.  

190-02246-01_g.pdf (garmin.com)

 

201Mooniac, can you post a picture of how you have it installed?

 

[201Mooniac]

2 hours ago, MisfitSELF said:

TOGA button is described in the GI275 Pilots Manual in the autopilot section -- page 197 for the electronic copy I'm looking at now.  

190-02246-01_g.pdf (garmin.com)

 

201Mooniac, can you post a picture of how you have it installed?

 

Are you asking for a picture of where the TOGA button is installed?  If so, here is one.  Otherwise please let me know exactly what you are looking for.

[TomW]

Great thread - So, my new GFC500 install (GI275/G500/dual GTN750xi) with TOGA button installed in left side of Throttle control (Bonanza B 36TC).

 Is it the general consensus then, that the TOGA button pushed at the MAWP will also signal the GTN and not require looking at navigator for extra "touch" on GTN to activate the Missed?

Thanks for input.

Tom 

[PT20J]

24 minutes ago, TomW said:

Great thread - So, my new GFC500 install (GI275/G500/dual GTN750xi) with TOGA button installed in left side of Throttle control (Bonanza B 36TC).

 Is it the general consensus then, that the TOGA button pushed at the MAWP will also signal the GTN and not require looking at navigator for extra "touch" on GTN to activate the Missed?

Thanks for input.

Tom 

So long as it is wired and configured during installation, yes. If you have a GTN and GFC 500, the GTN will sequence through the missed approach waypoints and the GFC 500 stays engaged and initiates a wings level constant pitch climb. 

Skip