Autopilot Nav mode

[lalnaes]

I have a system with two 10 inch SkyView screens and SV32 servos. I also have a Garmin aera 500 connected to the system which I use as my primary GPS source for flight planning and tracking. When I track a course to a waypoint and have the autopilot set in Nav mode, it will work fine for about 10 to 15 minutes and then switch to Track mode. I haven't tested this with 3.2, but I did have the same problem with both 3.0 and 3.1. Any suggestions?

 

[beno]

I have same problem with version 3.1.1 and Garmin 695.

When checking serial data output on setup screen I found out, that there are approx 1 or 2s random interval with signal loss from GPS. It happened sometimes after 10 or 20 minutes, sometimes after 1 minute or even shorter.

Didn't try yet with 3.2. In the Dynon change log I've read, that there is some serial communication improvement in 3.2. I hope that will help.

 

[n223rv]

I had the same problem with a 496 and my Tru Trak autopilot on my RV-4. I believe it is an issue with momentary losses of communication. I have not noticed it on my RV-10 with the Skyview and 696, but I typically fly it using the skyview GPS
-Mike Kraus

 

[gcanyon]

I also have had this issue ongoing. I am using a Garmin 696 and sometimes it will hold connection and then sometimes not .

Does 3.2 help??

 

[lalnaes]

I checked the Garmin aera user manual and it appears that the interface can be set to normal or fast. In the latter setting, fewer sentence types (less GPS-data) is being transmitted. I'll test it tomorrow to see if the fast setting has the minimum data needed to follow a track towards a series of waypoints in a flight plan.

 

[beno]

I did try many interface setup combinations (slow, fast..) with same results. Until this thread I have been thinking, that my problems are related to the wiring in my airplane. Now I see, that I am not the only one with this problem, so there could me a more sophisticated problem source.

It looks like, that serial communication between GPS and Skyview is not 100% reliable. If that can't be solved in HW possibly Dynon can change Skyview to ignore 1 or 2s signal loss from GPS.

 

[dynonsupport]

We already have a timeout that allows quite a bit of loss from the Garmin before we give up, so it's a balance between waiting a long time and switching when the signal is actually gone.

We're working on making this better in future software, but there were no changes in 3.2 for this. As you can see, other companies have struggled with this too as it's hard to deal with the Garmins just going out to Lunch sometimes.

It's not us. It's the Garmin actually stopping transmitting at times for a few seconds.

 

[beno]

Thanks Dynon for that helpful info.

When there is a GPS signal timeout, Skyview switches from NAV to TRACK mode (probably from safety reasons). That means sometimes completely different course.

It would be more practical to keep last GPS course, like automaticaly sinhronizing track bug to last known GPS course. Then, when signal comes back automaticaly switching back to NAV (and giving some message in status area).

Currently, I have to watch constantly at AP status and switch it back on when signal returns.

I think, we are not able to convince Garmin to change their firmware. Dynon is much more responsive here, so Dynon will find some workaround.