"What version of the Ardupilot code are you using? I haven't looked at the newer ones (still running with an old one since it works for what I do), it might be that patch doesn't work anymore. Does it compile cleanly without the patch?"

"It was so long ago I fiddled with the code that I am not entirely sure of what I was actually flew with (I set it up and left it alone and just flew it).
I did get rid of the forward-pitch tendency by just trimming it, I remember lowering the back a…"

"I had an ESC glitch mid-flight (bad connection somewhere), had nothing to do with the APM. Lost power to the front-right motor, made a roll and inverted dive into terrain."

"I flew it earlier this summer, but crashed it and broke the frame and have not had time to rebuild it. Haven't looked at the newer source code (like 3.1), but the patch is pretty simple and should be easy enough to rewrite for it."

"I hacked together a quick patch (against the current master branch), it is just a Y6 frame with two motors removed. It at least compiles, but I have no idea if it flies... I don't know if it requires some compensation for the fact that there are two…"