What causes adverse yaw during a turn entry?

Adverse yaw is a phenomenon that occurs during a turn, and it is primarily influenced by the difference in drag between the wings. When the aircraft begins to turn, the aileron on the wing that is being lowered (the wing that is turning into the turn) deflects downward, which increases lift on that wing. However, this also leads to an increase in induced drag because induced drag is directly related to lift. Conversely, the aileron on the opposite wing (the wing that is raised) is deflected upward, which decreases lift and, consequently, decreases induced drag.

The net effect of these changes is that the wing with the increased lift (and increased induced drag) causes the aircraft to yaw towards the opposite direction of the turn. This yawing motion can make the aircraft feel like it is skidding or slipping in the turn, which is a characteristic of adverse yaw. Therefore, the key to understanding adverse yaw lies in recognizing how the differential drag created by the aileron positions during a turn entry affects the aircraft’s yaw behavior.

In this context, other options, while relevant to aspects of flight control and lift, do not correctly explain the underlying mechanics of why adverse yaw specifically occurs during a turn entry.