Some airplanes require right thrust built in to compensate for torque. others do not. If you built as per plans it will be alright. Also down thrust is also sometimes needed. After experience, seasoned flyer's tweak their airplanes by adding right or down thrust simply by adding spacers behind the motor mount until the desiered result is achieved. A good way to tell if down thrust is needed, supposing that your balance is correct, and the angle of attack of the wing and horizontal stab is correct. If your plane flys level with down trim noticeable on the elevator. add down thrust and the elevator will be straight.Its kinda trial and error.The same is true for right thrust, if your plane is trimmed to the right to fly straight then a little right thrust might be needed. most traines are very stable so it would not be as noticeable as on a pattern plane. hope this helps.