Discussions

I am hoping someone can point me in the right direction on this.

This is my fourth APM build and I have 3 quads that fly very well with APM2.6

This is my first tricopter with APM and I have a problem making me want pull hair out.

I am testing in STABILIZE mode before moving forward to any other mode.  The tricopter flies and responds well to commands.  However, it seems to require maximum (!) pitch back trim to keep it from wanting to go into forward flight.  I have re-leveled it very carefully but noted that in telemetry logs, I see that APM seems to be wanting to put the copter into a -10 (nose down) attitude instead of level.

I have tried the not so clean way of taking care of this -- level it with nose up 10 degrees instead of truly level, and this works great... but I am not satisfied with this and am afraid of later issues.

Possibly relevant information:

1) APM is mounted with arrow facing left of tricopter (270 YAW rotation), but it is configured for this and all flying controls are correct.

2) Motors on this copter have non-standard rotations as follows:

   motor 1) CCW

   motor 2) CW

   motor 4) (tail) CCW

Question:  on Motor Test in mission planner, what motor number do motor "A" "B" and "C" correspond to?  Mine seems to do the follow:  Test Motor A -- front right,  Test Motor B -- tail motor, Test Motor C -- yaw servo rotates to one side (??)  However, it still flies fine...   I tried searching, but can't find what motor numbers the motors letters should correctly correspond to.

Also, I understand that motors 1 and 2 spin directions are opposite what is recommended, but the build was initially running a KK board fine like this, and the way the hardware is set up makes it absurdly difficult to swap these around without dismantling the whole thing (wires are inside carbon tubes).  This is the only thing I could think is causing any sort of issue, but I am doubtful how it would cause the APM to want to pitch forward when leveled properly...

Any help appreciated.