But to correct the left drift (if it is actually drifting left and not rotating left!), use the roll (left/right cyclic) trim to compensate - just a couple of clicks to the right should be plenty. If it is rotating to the left (yaw) then adjust the rudder (yaw) trim to the right a couple of clicks. Once you get better you can adjust the trim on the 3n1 to get it very centered, however, it is very sensitive - couple of degrees rotation on the adjustment is all that is needed ususally. (BTW, since it IS so sensitive, and I can't think of anyone that would need to move it very far, why doesn't helimax put a pot with more resistance in the 3n1 so the adjustment isn't so sensitive!!!!)