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?

don't take this the wrong way but I think you're probably just giving too much input on the sticks. the heli will want to drift left on take off. you need to get up to about 6 feet in height to stop these problems.

the main thing is that you need to input constant small commands, trying to hover the heli is like trying to keep a ball bearing in the middle of a glass plate, if it starts to roll one way you don't do and extreme tilt to get it back to the middle, you do a very small movement.

go through radd's school of rotory flight and get a sim to practice on (they may be expensive but you'll spend the same amount on broken parts).

If you have computer radio or if you get one. You can set some EXPO to remove some of that sensitivity unitl you get better.