Warning: Don't stall while in AUTOTUNE or CRUISE mode!

I forgot I was in AUTOTUNE mode and wanted to test my plane’s stall behavior. I ended up in a clockwise death spiral and lost 1,200ft (365m) before finally getting out of it by switching to manual. (I also tried CRUISE during that time but that was the same result.) After analyzing the logs, and the google earth mkz file, the cause was that the RC out values during the spiral were stuck at full left aileron (good), full up elevator (not good), and half left rudder. My elevator has a huge amount of travel so the plane was never going straight (down) enough I guess to get the right airflow over the wings during the spiral. As soon as I switched to MANUAL, the elevator straightened out, airflow returned to normal, and I got roll control back.

yes, this is not just a problem with autotune or cruise, it is any stabilized mode. ArduPilot is good at lowering the chance of a stall, but bad at getting out of a stall for many aircraft types. We have discussed various ways to fix this, but for now MANUAL is the right answer.

Hence the term ’ 3 mistakes high’ ! lol Good job captain! Bet your adrenaline was going there for a minute! Did you eventually succeed at using autotune mode? I am building a new model [ Sig Seniorita …LOTS OF WORK ] not sure I want to risk it.

Here is the video of the event

Wow, that was a fully developed spin… that was a little hard to watch. Very nice recovery though! Well done.