You\'ll never get a plane that always flies level without SAS - as fuel drains the centre of mass will also change and throw off your balance. Use SAS for normal flight, to lock your plane into its heading. When you want to turn, turn SAS off, roll SLIGHTLY in the direction you want to turn, then pull up a little. Don\'t touch the rudder, as a rule. Planes are usually more balanced and well-behaved if you have a very large overall wing area, since wings help redirect your movement as well as generate lift.