What is a key effect of adverse yaw during a turn?

Adverse yaw is a phenomenon that occurs during a turn where the aircraft yaws in the opposite direction of the intended turn. This effect arises due to the differential lift and drag generated by the ailerons when one wing is raised, typically causing that wing to produce more lift but also more drag.

When the pilot initiates a turn by deflecting the ailerons, the aileron on the wing that is intended to rise (the "up" aileron) generates increased lift, but at the same time, it also increases drag. Conversely, the aileron on the opposite wing (the "down" aileron) generates less lift and less drag. As a result, the increased drag on the wing with the up aileron causes the aircraft to yaw toward the opposite direction of the turn. This uncommanded yaw must be countered by the pilot using rudder input to maintain a coordinated turn.

Understanding adverse yaw is essential for pilots because it emphasizes the importance of using both ailerons and rudder to achieve smooth and coordinated turns, which affects overall aircraft handling and performance during flight.