The only thing that I never did was fly it with one engine, I should have tried with just the front engine, I believe I did get the CofG as close as possible but the issues with multiple thrust lines which are exagerated by the front canards being able to be anywhere from 10 degress negative to 10 degrees positive with no indication in the instructions as to there angle relative to the main wing is I believe problematic. I was fortunate and had 4 or 5 flights which all nearly ended in disaster, one word of advice, if it starts to porpoise and pitch up and down close the throttles, mine actually flew (glided) well - this suggested that the issues were related to when the motors were working and this is why I am suggesting the thrust lines are the issue. Good luck with your machine, it looks very nice in the air and is a croud pleaser but holy cow - a handful is an understatement