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G3X Without GMC controller

S

sinflrobot

Member
I'm getting close to finishing my panel update, and was wanting to get opinions on the necessity of the GMC 307/507 for use on the G3X non-touch.

For reference, this is a budget "new to me" setup: dual gdu 370's controlling trutrak gemini AP and servos. GNS480 for IFR GPS.

Just curious if others think the extra buttons and knobs add a lot of extra value? worth the extra AMU?
 
I'm cutting my panel right now for a G3x dual touchscreen and I'm putting a GNC507 front and center at the top of the stack.

For a VFR only application, I think controlling it from the pfd would be okay, but I personally wouldn't want to go that way on an IFR autopilot. I like having a readily available control head where I can poke buttons and turn knobs immediately if I have to modify something.

FYI- the GNC507 is super easy to put in. It just requires the right size hole. No rack or back shells, and only one plug in the back of it. Plus it's only a couple of inches deep.
 
GMC507 Recommended

I have the set-up of 2 non-touch G3X and GX AP (Trutrak). 200 hrs w/o the external panel.

IFR use it is a lot more button pushing on the PFD than with the GMC.
Active mode indication is always visible.
IFR - you can NOT use TOGA w/o the GMC
I would get the 507 as it has more useful functionality.

You can fly without the GMC, but without a doubt the GMC makes it easier and provides the TOGA function. GMC507 ="recommended"

I would not hesitate to install one for the $ while assembling a new panel.
 
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I have the dual touch system and the 305 panel module. I am still learning the ap system but use both the screen and 305 about equal. The screen is easier to understand to me but the 305 is easier to use if it is bumpy. The 307 has the heading knob and altitude knob. I think I would like that.

I am going to upgrade to the 307. It is a direct swap - same size and just unplug the cable and plug it into the new unit. I would get the 507 - they are the same or about the same price but it is a lot of re-wiring and I just dnt want to do that! The only difference in function is the 507 has a track button. Im sure that is a good thing for IFR and even VFR, but not worth the wiring changes.
 
Are you sure the 507 will interface meaningfully with a TruTrak AP? Can you do anything other than select the heading (or track) to follow via the GPS(S) input? I would check what the 507 will provide before you buy one.
 
Southern Pete said:
Are you sure the 507 will interface meaningfully with a TruTrak AP? Can you do anything other than select the heading (or track) to follow via the GPS(S) input? I would check what the 507 will provide before you buy one.
Click to expand...

Good point. I didnt notice that it was TruTrak. If it is not the Garmin servos, I wouldnt count on it working until you do some research.

I will be making the change this spring and you are welcome to try my 305 at that time if you want.
 
I don't think any of the GNC panels will control a non Garmin autopilot. You would be able to set the altitude and heading (not sure if those sync through to the TruTrak) but none of the mode buttons will do anything without Garmin servos
 
So….we’ve got a dual-screen non-touch system with a Tru-Trak A/P in our -3 (I think it might have ben the first G3X delivered), and it works just fine without the dedicated panel. At the time, the panel didn’t exist, so we just learned how to use it as designed, and it does everything we need it to do.

When we installed one of the first G3X Touch systems in the -6, it came with the panel, and the Garmin servos, and I really like that method of control - its better than using the screen, but the screen is still more than adequate.

For a budget system, I’d be plenty happy without the panel - just learn how to work the system, and it will do everything you need.

Paul
 
Flew behind a TT in my last plane and the -6A came with the GFC500 autopilot head. It is night and day. YES the button and knobs are amazing, IFR is much easier when everything is right there and at the ready. muscle memory will kick in and sections become second nature very quickly. If I were to get another plane I would WANT the Garmin AP in it for sure.
 
BillL said:
IFR - you can NOT use TOGA w/o the GMC
Click to expand...

The GMC 507 provides a convenient place to connect a TOGA pushbutton, but if you don't have a GMC 507 you could use any of the other discrete inputs in the G3X system for this function.

ColoradoSolar said:
I don't think any of the GNC panels will control a non Garmin autopilot. You would be able to set the altitude and heading (not sure if those sync through to the TruTrak) but none of the mode buttons will do anything without Garmin servos
Click to expand...

I have a fair amount of time in various aircraft equipped with Trutrak autopilots and G3X flight displays, and in general the autopilot and flight director work very well together. There are numerous reasons to prefer the Garmin servos, but if you already have the correct Trutrak autopilot it's certainly a workable setup.

Quoting from section 2.1.1.15 of the current G3X installation manual: (revision AP)

Certain third-party autopilots that are designed to be integrated with the G3X system may also be used in conjunction with the G3X flight director and GMC control panel. Consult the third-party autopilot manufacturer for further information.
Click to expand...

There are various Trutrak autopilot models that support this interface - I don't know about the Gemini model specifically.
 
mburch said:
The GMC 507 provides a convenient place to connect a TOGA pushbutton, but if you don't have a GMC 507 you could use any of the other discrete inputs in the G3X system for this function.
Click to expand...

So you think the TOGA will work with the G3X non-touch and no GMC?

Mine will not, and in spite of many Gamin discussions with many Garmin help line people it still does not work. I finally got a SW guy who said it must have a GMC panel to function. Believe me, I made a real nuisance of myself.

If you are absolutely sure of your statement, please let me know so the specifics can be reviewed, as I sure would like to have mine work.

edit: crickets
 
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TruTrak AP with G3X?

I am considering an upgrade to my panel with a G3X. I currently have a TruTrak Gemini AP and a GTN-650. Would anyone with that combination help me with a couple of questions?

Would all the G3X autopilot functions work the same as if Garmin servos were installed? For example: VNAV, Approach, TOGA, etc

Does a GMC 507 work with the TruTrak the same as with Garmin servos?

Any other limitations?

Any information would be appreciated. Thanks.
 
If your G3X controls your A/P via RS-232, the 507 will operate your A/P thru the G3X. When you add the 507 you will gain the additional feature of having the F/D operate without having the A/P engaged. The features available using the 507 are limited by the auto pilots functionality.
 
Ken Harrill said:
I am considering an upgrade to my panel with a G3X. I currently have a TruTrak Gemini AP and a GTN-650. Would anyone with that combination help me with a couple of questions?

Would all the G3X autopilot functions work the same as if Garmin servos were installed? For example: VNAV, Approach, TOGA, etc

Does a GMC 507 work with the TruTrak the same as with Garmin servos?

Any other limitations?
Click to expand...

Ken, did you find an answer to this? I'm considering a similar upgrade and weighing having G3X drive my Trutrak AP, versus swapping the TT servos for the GSA 28 servos. I've made myself familiar with the functioning of the G3X autopilot, but don't have specifics about what (if any) modes or functions are not available when using the Trutrak.
 
Ken Harrill said:
I am considering an upgrade to my panel with a G3X. I currently have a TruTrak Gemini AP and a GTN-650. Would anyone with that combination help me with a couple of questions?

Would all the G3X autopilot functions work the same as if Garmin servos were installed? For example: VNAV, Approach, TOGA, etc

Does a GMC 507 work with the TruTrak the same as with Garmin servos?

Any other limitations?

Any information would be appreciated. Thanks.
Click to expand...

jwyatt said:
Ken, did you find an answer to this? I'm considering a similar upgrade and weighing having G3X drive my Trutrak AP, versus swapping the TT servos for the GSA 28 servos. I've made myself familiar with the functioning of the G3X autopilot, but don't have specifics about what (if any) modes or functions are not available when using the Trutrak.
Click to expand...

Way back in the day I did use the TT GX Pilot with my G3X system. I think that was before the GMC30X came out.

The install docs still show interconnects for a non Garmin AP and also includes the GMC 30X wiring but the information around what works and what does not is sparse.

I would shoot the guys over at TeamX an email and hopefully they will clarify.
 
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8MikeXray said:
When you add the 507 you will gain the additional feature of having the F/D operate without having the A/P engaged.
Click to expand...

This seems like a really important feature to me. Lets you see what the A/P is going to try to do before you hit the 'engage' button.
 
Another difference

I don't think the 307 supports audio warnings for autopilot disconnect, etc. If I'm wrong about this, someone please tell me! :)

rockwoodrv9 said:
The only difference in function is the 507 has a track button. Im sure that is a good thing for IFR and even VFR, but not worth the wiring changes.
Click to expand...
 
Ken Harrill said:
I am considering an upgrade to my panel with a G3X. I currently have a TruTrak Gemini AP and a GTN-650.
Click to expand...

G3X non-touch (GDU 37x displays) or G3X Touch (GDU 4xx displays)? The supported capabilities will depend on which displays you have.

Dugaru said:
I don't think the 307 supports audio warnings for autopilot disconnect, etc. If I'm wrong about this, someone please tell me! :)
Click to expand...

No, the GMC 3xx mode control panel does not have any audio output capability, but this is not relevant to a G3X system, where the GDU displays provide AFCS audio alerting.
 
Dugaru said:
I don't think the 307 supports audio warnings for autopilot disconnect, etc. If I'm wrong about this, someone please tell me! :)
Click to expand...

That was my understanding but I am no expert and could be remembering incorrectly what the garmin tech said. Im not willing to do the extra wiring for the 507 so I am stuck with the 307 if I want to upgrade. I am happy with the 305 but would like the knob steering and knob altitude.
 
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