Flight lines discrepancy

I have done a flight mission (mission planner)
Distance between flight line area 90 meters.
But, when flight is done I have 2 different distances. Flight line distance 80 meters and another 100 meters.
I have not idea how to correct it


Let me guess, this is a Skywalker?

Not quite sure what you mean. Are you saying some flights are 80m apart and others are 100m? Is it particular to a certain direction the plane flies? Is it every other flight line? Do you have a log of the flight - preferably a dataflash log?
Thanks, Grant.

His plane is flying in a slip due to torque/P-factor/Spiraling Slipstream. For some reason no one has been able to explain to me, the autopilot can’t cope with this and it tracks right of course on all flight lines. This results in uneven sidelap on a low mower pattern.
This is a well documented problem and there are many posts on the topic here and on DIYDrones. It is most common on the widebody Skywalkers.
The only fix I found was to feed a tremendous amount of left rudder trim. So much rudder trim, that it’s difficult to fly in Manual. I actually had to program the Taranis to remove the rudder trim if the mode switch is in Manual.
I tried to tune the yaw controller which helps a bit, but not enough.

This is an on going issue for years that never really got resolved.

  1. Why can’t the autopilot maintain centerline if it’s not in coordinated flight?
  2. Why can’t the yaw controller force the plane to stay in coordinated flight?

As it is, the plane flys with one wing down about 5-7 degrees and tracks with an offset to the right of course.

More here:
Plane tracks wp line with 10 deg left bank angle

And here…
Flight path offset

And here…
Plane always flies to right of waypoints

And here…
diydrones.com/forum/topics/plane … e=activity

I am so sorry. I habe seen now messages about post.
Forum did not send any information to me that were messages.
I have not bib log now, I will upload next monday.