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Dugaru
06-10-2018, 09:41 PM
Okay, so the other day after takeoff I engaged my Garmin autopilot (my setup is a G5, GSA28 pitch and roll servos, and a GMC 307). I used the CWS/disconnect button on the stick, and the autopilot engaged at the existing pitch and roll. I love that feature.

I then configured it to follow the flight plan in my Garmin 430W (using the NAV button on the 307) and to go to my first assigned altitude, using the VS mode. All seemed to be going fine.

Instead of turning left at the first waypoint as planned, however, the autopilot ran the aileron trim all the way to the right, and then disconnected (yellow flashing AP). I got the aircraft back on course, centered the trim, and tried to engage the autopilot again. The same thing happened (trim right, then disconnect), followed by an AP with a red slash through it. I then got a red AFCS indication at the top of the G5. At that point, I was unable to turn the autopilot on, and neither the heading nor altitude dials on the 307 had any effect. So I hand flew from that point on.

After landing, on the "device info" page, the servos and 307 were grayed out. There was one "transmit error" logged.

Still on the ground, I recycled the breaker and at that point, the autopilot and 307 came back to life. The autopilot now turns off and on. I now have green checkboxes for the servos and 307. I ran the preflight test set forth in the manual and again everything seemed to be working correctly.

Since then, I've powered up and down several times, and the system seems to come up fine after the "PFT" indication.

I haven't flight tested it yet. Before doing so, does anyone have any ideas regarding what may have caused this failure? I'm running the latest 5.20 software, for what that's worth.

Thanks
Doug

jthocker
06-11-2018, 06:52 AM
Lots of people misinterpret how to test the autotrim. On the screen they press “test” and then the trim “left” and “right” options on the SCREEN become available. They then proceed to use the stick buttons to “test” instead of the screen buttons. Good chance the autotrim is reversed.

Oh yes, version 5.9 is the latest!

Walt
06-11-2018, 07:03 AM
I always suggest folks first test the AP with autotrim turned off to be sure the basic operation of the AP is working good before activating autotrim.
And I agree with Jon, sounds like the ail autotrim make be backwards.

g3xpert
06-11-2018, 07:47 AM
Okay, so the other day after takeoff I engaged my Garmin autopilot (my setup is a G5, GSA28 pitch and roll servos, and a GMC 307). I used the CWS/disconnect button on the stick, and the autopilot engaged at the existing pitch and roll. I love that feature.

I then configured it to follow the flight plan in my Garmin 430W (using the NAV button on the 307) and to go to my first assigned altitude, using the VS mode. All seemed to be going fine.

Instead of turning left at the first waypoint as planned, however, the autopilot ran the aileron trim all the way to the right, and then disconnected (yellow flashing AP). I got the aircraft back on course, centered the trim, and tried to engage the autopilot again. The same thing happened (trim right, then disconnect), followed by an AP with a red slash through it. I then got a red AFCS indication at the top of the G5. At that point, I was unable to turn the autopilot on, and neither the heading nor altitude dials on the 307 had any effect. So I hand flew from that point on.

After landing, on the "device info" page, the servos and 307 were grayed out. There was one "transmit error" logged.

Still on the ground, I recycled the breaker and at that point, the autopilot and 307 came back to life. The autopilot now turns off and on. I now have green checkboxes for the servos and 307. I ran the preflight test set forth in the manual and again everything seemed to be working correctly.

Since then, I've powered up and down several times, and the system seems to come up fine after the "PFT" indication.

I haven't flight tested it yet. Before doing so, does anyone have any ideas regarding what may have caused this failure? I'm running the latest 5.20 software, for what that's worth.

Thanks
Doug

Hello Doug,

As others have commented, it is possible that the auto-trim is reversed (see this thread (http://www.vansairforce.com/community/showthread.php?p=1041668) for more information), but the autopilot doesn't disconnect for out-of-trim conditions.

You are, of course, welcome to continue to solicit help here, but we recommend you contact us directly so we can assist you in collecting a flight data log which will contain the reason for the in-flight disconnect.

Thanks,
Steve

Mark H
06-11-2018, 07:50 AM
Jon, it doesn?t sound like Doug has a G3X Touch, just a G5 with autopilot. Version 5.20 is the latest software for the G5. The 5.90 is for the G3X Touch.

jthocker
06-11-2018, 09:13 AM
Jon, it doesn?t sound like Doug has a G3X Touch, just a G5 with autopilot. Version 5.20 is the latest software for the G5. The 5.90 is for the G3X Touch.

Oops! Missed that. Thanks, and I?ll be sure to RTFQ in the future!😳

Dugaru
06-11-2018, 09:16 AM
Sounds good, I'll data log my next flight and contact you directly.

Hello Doug,

As others have commented, it is possible that the auto-trim is reversed (see this thread (http://www.vansairforce.com/community/showthread.php?p=1041668) for more information), but the autopilot doesn't disconnect for out-of-trim conditions.

You are, of course, welcome to continue to solicit help here, but we recommend you contact us directly so we can assist you in collecting a flight data log which will contain the reason for the in-flight disconnect.

Thanks,
Steve

Dugaru
06-14-2018, 10:39 AM
So of course the autopilot now appears to be working perfectly (as it was for months previously).

If I just leave a microSD card in the slot, will it continue to log data (and overwrite old data) so that I can catch it in the act if it does it again?

Somewhat related question: is it possible for my setup to generate an audible warning when the autopilot disconnects? The flashing yellow AP can be easy to miss, since the G5 is not my primary attitude indicator display.

Thanks
DMG

Sounds good, I'll data log my next flight and contact you directly.

vic syracuse
06-14-2018, 10:55 AM
Why would the autotrim decide to be reversed when it has been working correctly for so long?

Vic

Dugaru
06-14-2018, 11:50 AM
Why would the autotrim decide to be reversed when it has been working correctly for so long?

Vic

Also my conclusion. I don't think there's anything wrong with the autotrim setup.

And per Garmin above, the autopilot doesn't give up and disconnect due to out-of-trim conditions in any event. But I can confirm that in both of my recent losses of the autopilot function, it first trimmed the ailerons all the way to the right.

Walt
06-14-2018, 12:06 PM
Why would the autotrim decide to be reversed when it has been working correctly for so long?

Vic

I'm pretty sure the original post said nothing of working correctly, and some of us may have "assumed" this was a new install problem.

That's why the internet is not so good for troubleshooting, you often get only some of the info.

Dugaru
06-17-2018, 08:35 PM
Autopilot continues to work correctly. I've confirm the trim is properly configured; I ran the gas out of the left wing for a long period and the autopilot dutifully trimmed into the "light" wing.