When i try to take off, i put max. RPS and accelerating, after a few secs my plane turns to right (it always turns to north).
1. Autopilot(AP) is off
2. Trims are centered
3. Wind is zero
4. Your flying the aircraft, no aircraft will fly straight without pilot in put for more than a few seconds.
5. Fuel is even between L and R tanks(If you have control)
6. If your flying with the keyboard, stop, get a joy stick.
If aircraft always turns north with the AP on, then you need to set the AP to do what you want it to.