I'm assembling my first quad.  It isn't stable when we try to fly it and I've been trying to figure out why.   Today I stumbled upon what probably is the answer.When the quad is started up, the artificial horizon is steady.   It will sit there for…

We just built a quad here at the QC Co-Lab, but we can't figure out why it won't stabilize.  The left/right axis is stable but the front back axis either seems unresponsive or actually backwards (When you tip it forward the back engine sometimes…