What is the primary effect of adverse yaw during a turn?

The primary effect of adverse yaw during a turn is increased drag. Adverse yaw occurs when the aircraft is in a coordinated turn, and it typically results from the differential lift created by the wings. When the pilot initiates a turn, the aileron on the wing being lowered (the wing that is rising in the turn) creates more lift, while the aileron on the rising wing creates more drag due to its downward movement through the air.

This additional drag on the wing that is rising causes the aircraft to yaw in the opposite direction of the intended turn, which can be particularly noticeable during turns. Although the aircraft is attempting to turn left, for example, it may initially yaw to the right due to the increased drag on the left wing. This yaw effect needs to be countered with coordinated rudder input to maintain a smooth turn, which is critical for both efficiency and safety during flight. Understanding the dynamics of adverse yaw is essential for pilots to execute turns effectively and maintain control of the aircraft.