Need help with left yaw issue - no response to input - clockwise forward movement/drift

Hi All,

I need help figuring out a yaw issue.

I just test flew a new build for the first time:

Orange Cube w/ ADS-B carrier board
U5 v2.0 T-Motors
16.5 T-Motor props
Here3 GPS
Air A40 ESC T-Motor
frame is custom (3D printed)

First flight was a simple takeoff, short hover, and return, all looked good.

The second flight was a 3 waypoint program with the 4th waypoint being RTL. The quad hit all waypoints at the designated altitude and landed fine, though it did so while yawing slowly in a right rotation.

The third flight was a takeoff to 10m then put into Autotune. Instead of the standard twitch dance of Autotune, the drone did a slowly expanding spiral in a clockwise rotation.

I kicked it into position hold and tested each input:

  • Ascend and descend are perfect
  • Right yaw seems fine, but full left yaw produces almost no response.
  • Forward input causes the drone to move forward while curling to the right.
  • I can’t accurately describe what back stick does as by this time I was frustrated and just landed.

I downloaded the data flash logs and they can be found HERE

Any help will be very appreciated! Thanks for reading this and stay healthy out there!



Link to the .bin flight log. Tlog’s are of limited value. But a quick look at the extracted parameters shows you haven’t done the Initial Tuning which should be done before Auto Tune anyway. Or the maiden flight for that matter.
Connect to Mission Planner and hit Alt>A for the tuning plug-in, enter the prompted values and make the changes. Then read the Wiki about the process for configuring the Dynamic Notch filter.

Then think about running Auto Tune.

Thanks for the reply Dave, I’ll do it and circle back here with today’s test flight results.