Which control surface is used in combination with ailerons for turns while flying?

The rudder is the control surface used in combination with ailerons for making turns while flying. When an aircraft turns, the ailerons create differential lift by raising one wing while lowering the other. This action causes the aircraft to roll in the direction of the turn. However, using only ailerons can lead to adverse yaw, where the aircraft tends to yaw (or turn) opposite to the direction of the roll due to the increased drag on the wing that is generating more lift.

To counteract this adverse yaw and maintain coordinated flight, the rudder is used to steer the nose of the aircraft in the direction of the turn. By applying rudder input in conjunction with aileron input, pilots achieve a smooth and coordinated turn, minimizing the risk of skidding or slipping through the turn. This coordination is essential for maintaining control and ensuring that the aircraft remains level during the maneuver.

Using the elevator, trim tab, or flaps would not achieve this coordination in turns. The elevator primarily controls pitch, while the trim tab is used for fine adjustments to reduce pilot workload, and flaps are used to increase lift and drag during takeoff and landing, rather than for turning.