I've recently tried to setup APM for my new flying wing and discovered that it is not safe to fly in other than Manual modes =( The reason is servo throws for most flying wings must be limited, but APM limits them only in Manual, in all other modes servos goes to endpoints.
After some googling I've found 2 bugs submitted to issue logger on google code of arduplane:
Elevon control throw for manual mode does not match control throw for other modes
|Issue 686:||Servo limits (maximum throw) is not working in stabilize, fbw and other modes.|
Another helpful user - Vladimir Popov commented:
Comment by Vladimir Popov yesterday
I just investigated firmware sourses... Stick deflections are added to servo output a bit tricky - automatic output signal is scaled down to leave place for manual signal. It seems Ok, but the algorithm is internally limited - manual signal must not exceed +-400 ms from trimmed value. I do not know why. So, don't move sticks too much...
I think you can ask developers about this limitation. Function stabilize() in Attitude.pde.
In RTL mode sticks are not mixed at all.
So what should we change in order to make it work? Thanks for the help!