If you spend much time around old-time pilots, you’ll eventually get around to one of them going off on a rant about how the kids today don’t know what the rudder pedals are for. From their perspective, they’re right. A lot of the airplanes the old-timers grew up with had squirrelly aerodynamics, exemplified by the characteristic known today—probably then, too—as adverse yaw. The FAA defines adverse yaw as a “condition of flight in which the nose of an airplane tends to yaw toward the outside of the turn. This is caused by the higher induced drag on the outside wing, which is also producing more lift. Induced drag is a by-product of the lift associated with the outside wing.” The graphic below explores the behavior exhibited in a right bank.
If we’re doing it right, we use inside rudder to counter the yawing tendency by keeping the ball centered, minimizing any unpleasant sensations and ensuring the airplane is pointed in the direction we want, not what the physics laws force upon us. In part, it is the younger pilots’ failure to understand adverse yaw when banking and proactively address it with appropriate, coordinated rudder input that has the old-timers shaking their heads. They’re not wrong, although newer airplanes are engineered to minimize adverse yaw, so it’s not as noticeable or objectionable. But there’s more.
