Any requirement to switch elevon mixing to elevon output?


New to the APM, but have read the documentations extensively. Had good experience with the previous firmware 3.0.5, but when I upgraded my APM 2.5.x to 3.1.0, which was installed in a flying wing setup with TX elevon mixing, it seemed the ground checks worked ok with a cursory glance: FBWA, and elevons moved as desired while changing pitch and roll. Unfortunately, in the air, every time I switched from manual mode to either FBWA or AUTOTUNE mode, it would immediately roll right and I would need to switch to manual to recover. On landing, and a closer examination, it seemed like one of the elevon control surfaces moved with a little more authority than the other. Thinking it was the Roll P value, I lowered it, but that only slowed the roll.

I then set the APM to default values, re-flashed the firmware, and noticed that Mission Planner wasn’t allowing me to set elevon mixing anymore, as it complained about this not being supported in Arduplane. I went into advanced configuration, and noticed the elevon output option, which I hadn’t noticed before. After changing the TX configuration to remove the elevon mixing, and configuring the elevon output correctly, it appears the control surfaces now behave as they I expected prior to my first firmware update.

My question: is elevon mixing now deprecated / removed? It doesn’t appear to be mentioned in the release notes for 3.1.0 – but I haven’t looked at the Mission Planner updates either – both updated around the same time.

I haven’t relaunched / tried AUTOTUNE yet, but will update this once I have this week.


the old elevon mixing code is still supported, but not recommended.