I am kind of new to the r/c heli hobby (about a month) but I have worked in the aviation maintenance industry for several years and have a fairly good understanding of flight. But what has been frustrating is my r/c heli has a very steady left drift or right that I can not overcome with trim settings. It also has a prety steady left or right rudder drift that, when trimmed either left or right, does not correct the issue. It has been about as impossible as anything I have ever done to get this thing off of the ground. At one point, I gave it substantial throttle and got it up about 15 feet in the air and it was all over the place (and quite uncontrollable I might add). I had to kill the throttle and crash land in the neighbor's bushes (it was that or else it was going through the second story bedroom window).

Simply put, I need some pointers on what to do. I have made adjustments to the trims with no avail as well as giving stick control when attempting take-off. It goes from one extreme to the other. Any advice from the more experienced crowd?