Copter Yaw During RTL Decent

Why would the ATT.DesYaw change during an RTL decent (verified in the log file). The octocopter will yaw 20 to 120 degrees during decent. In an attempt to midigate this issue we have put ‘Condition Yaw, set to 180’ command in just before the RTL in a mission. We have two of these aricraft and only one exhibits this behavior. It is nice to have two aircraft to compare (param files have been compared too).

I am using Copter version stable-4.0.7 with Mission Planner 1.3.74

Where is the aircraft getting heading info from during a decent?

Thanks all.

From the RC receiver. If there is noise in the yaw channel it may cause this. I had in it the past and fixed it by increasing the YAW cannel deadband parameter.

Thank you for the response. I’ll take a look at the Futaba 14G controller further. We did verify all gimbals on the controller we centered. Also, we used the same controller on both aircraft and only see the yaw’ing on one of the aircraft.

Thanks again!

The deadband is an ardupilot parameter, it might be different between the two systems.

I did not know that - thanks! We did compare both param files, but will certainly look at the deadband parameter.

Both param files (comparing two multirotor aircraft, one having the YAW issue) shows RC4_DZ = 20

The YAW seemed to occur with wind gusts - during the decent the copter is blown around and desired yaw (DesYaw) is changing, where is it getting heading information to maintain a constant heading?