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G3X Trutrak GX pilot pirep

jthocker

Well Known Member
Got a chance to check out the capabilities of my new G3X panel this weekend.
The G3X in and of itself is phenomenal and I will save any words on that for later. I wanted to report about the Tru trak GX pilot. I have flown tru tracks many times before and have always been impressed. The Dynon autopilot I recently removed was very adequate after MUCH tweaking. I flew it IFR numerous times and would not hesitate to install one again. It kept the "pink" line centered all the way to the runway.
The GX pilot on the other hand is AMAZING. For example, with the Dynon, while flying a long cross country in formation I would not engage the autopilot if I was following a Tru Trak. It would constantly converge or diverge from the other aircraft. It was never enough to displace the cdi, and would not be noticed if you weren't flying in formation, but still it was annoying enough for me just to hand fly it. Yesterday, leaving Halls, TN following an airshow, Fellow G3X/ GX pilot Greg "Greese" Reese and I climbed to 11,500 and headed for Cincinnati ( LUK).
Greg let the autopilot fly up to altitude, while I hand flew his wing. Upon level off, and established in "route" position, I engaged the autopilot direct LUK. Greg was at full throttle and I required something less. I found a setting that was LOP, and from there on I only touched the mixture control to vary fore and aft position. The "TWIN" autopilots kept us both vertically and horizontally spaced identically. They did this for over 250 nm.
I installed the GX pilot out of the box, looking only at the wiring diagram, tested the servos, clipped a pitch reversal wire, and flew it. I still have not looked at the rest of the installation manual, nor have I adjusted any settings.

There's also a GDL 39 to report on, and also the "Back up" comm to my PAR 100 EX, a GTN 650!! I've made 2 long cross countries the last 2 weekends, and the 650 never left the "start up" page!
 
Hey Jon,

thanks a lot for that report! I?m planning to install the G3X with the Trutrak GX next winter.
Your report makes me happy looking forward to that.

Best Regards,

Kai.
 
Jon, I haven't looked into it yet but do you have to mount anything else of the autopilot but the servos, since the G3X controls it? Avionics being bought around Feb next year..doin the G3X...haven't really decided if I need autopilot..my RV-8 will be VFR fun ship...I do IFR in other stuff....your thoughts on that would be appreciated too.
 
Jon, I haven't looked into it yet but do you have to mount anything else of the autopilot but the servos, since the G3X controls it? Avionics being bought around Feb next year..doin the G3X...haven't really decided if I need autopilot..my RV-8 will be VFR fun ship...I do IFR in other stuff....your thoughts on that would be appreciated too.

David,

You also need to mount the auto pilot head on your panel. Trutrak makes several OEM autopilots. The units for Advanced Flight and Garmin are very similiar, with the exception of slight changes for interfacing with their respective EFIS.

The EFIS technically isn't controlling the servos, that is the job of the autopilot. The EFIS is just sending data to the AP head as to which direction to steer the servos.

There are folks that will disagree, but I am of the belief that having an external AP head is a better system design for IFR use. If your EFIS fails, you can buy some think time by controlling the AP head directly.

Depending on your build timing, you may also want to look at Trutrak's Gemini AP. it would provide a backup EFIS for your G3x.
 
calibrating

In my first flights Gx-Pilot works perfect but know I have differences between the G3X trak and the GX-Pilot track about 4 degree, the gps source is the g3x so i dont know what it happen, the problem is that in cruise when i set ap heading hold the plane goes wandering, ball is centered and ap is on before engine start.

Second problem is when i make a turn the ap alt hold lost the control of the plane and if i disconect from the g3x softkey the servo continues torquing so i have to turn the CWS switch this is ath hight speeds.

Dies anybody know how to calibrate de GX-PILOT Giros I see some instructions in the digifligh manual but i dont know if it works in the GX-pilot.

Regards
 
In my first flights Gx-Pilot works perfect but know I have differences between the G3X trak and the GX-Pilot track about 4 degree, the gps source is the g3x so i dont know what it happen, the problem is that in cruise when i set ap heading hold the plane goes wandering, ball is centered and ap is on before engine start.

Second problem is when i make a turn the ap alt hold lost the control of the plane and if i disconect from the g3x softkey the servo continues torquing so i have to turn the CWS switch this is ath hight speeds.

Dies anybody know how to calibrate de GX-PILOT Giros I see some instructions in the digifligh manual but i dont know if it works in the GX-pilot.

Regards

You may get a quicker response by posting on Trutrak's support forum or giving them a call directly.

Bob
 
Last edited by a moderator:
In my first flights Gx-Pilot works perfect but know I have differences between the G3X trak and the GX-Pilot track about 4 degree, the gps source is the g3x so i dont know what it happen, the problem is that in cruise when i set ap heading hold the plane goes wandering, ball is centered and ap is on before engine start.

Regards

I had the same experience on my first flight. Turned out that I enabled heading mode not nav mode. The autopilot was flying the same heading it had when enabled rather than flying the GPS NAV course that will agree with each other. When in gps nav mode the track on my G3X, GPSMap 696 and Asus Transformer tablet running Garmin Pilot all agree. When in heading mode external weather conditions can cause your course to drift off.
 
In my first flights Gx-Pilot works perfect but know I have differences between the G3X trak and the GX-Pilot track about 4 degree, the gps source is the g3x so i dont know what it happen, the problem is that in cruise when i set ap heading hold the plane goes wandering, ball is centered and ap is on before engine start.

Second problem is when i make a turn the ap alt hold lost the control of the plane and if i disconect from the g3x softkey the servo continues torquing so i have to turn the CWS switch this is ath hight speeds.

Dies anybody know how to calibrate de GX-PILOT Giros I see some instructions in the digifligh manual but i dont know if it works in the GX-pilot.

Regards

The bolded segment could cause an issue. We really need the autopilot to be powered off during engine start. Once it's running you can power up. It sounds like you have a bit of a gyro offset that's been introduced. Start the engine, power up the autopilot, keep the aircraft stationary until the screen shows AP OFF. I'd also like you to do a gyro set. Once it shows AP OFF, continue holding the aircraft stationary and hold the autopilot knob in for about 45 seconds.

Let me know how it goes after that. Thanks!
 
the ap shows AP ON not OFF for some minutes, then the track still diferent than g3x, tomorow i will take long 200miles run and i will check again.

Thanks
 
If i power the ap in the ground the and the cws not conected de ap off apears as you said, but if y had the cws on the ap shows ap on.

If i power in the ground and coupled in the air the results take me to and uncontrollable plane.

If i power in level flight in ap mode no efis mode the ap works but in effis mode the plane starts wandering and if i make a turn in both modes the plane goes up or down loosening the control of the plane, al lows speed the efect is minos but at 167 knots tas its big.

I have some questions, is the taildragger ground position efect the giros?
Why i have wandering or zig zag only with the efis mode?
I check with alternate static source and the results dont vary.

Regards
 
When you power up on the ground, are making sure that the aircraft is not moving? Being a taildragger has no effect on the gyros, but if the aircraft is moving at any time during the PWR UP screen then that will have an effect.

Also, what version of software do you have? The version is displayed on the screen during power up.
 
There is newer software available but you cannot update it in the field. It has to be sent back to us for update. Contact me by PM if you'd like to do that. Thanks!
 
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