ORIGINAL: cshahrdar

hello,
thank you so much.

i believe the wing may not have been the problem at all.





that means that the fin leading edge is heading towards left side of airplane, and when thrust, which is aimed to right by 3 degrees, this air pressure (thrust/wind from motor) is greater on right side of fin instead of equally distributed on both right and left side. this turbulent air flow on the fin, which has a higher pressure on right side of "twisted" fin, and causes the plane to roll to left.

at least, this is my theory.

i carefully cut the coverite on the right and left side of fin base, and using a flexible thin saw blade, i detached the leading aspect of fin from fuselage all the way to rear except for the trailing 1 inch of it.

i then used a laser light, and attached to a flat ply wood, placed it on side of fin so that laser light was in front of fin, then slowly moved fin to the right until light was in center of fuselage and in line with propeller blade, which i placed upright and i also used the level which hung from prop hub.