Ace the Pilot Interview Mistakes
P.30/31
Dutch Roll Explanation:
It's a coupled lateral/directional oscillation that is dynamically stable but unsafe due to the oscillatory nature.
When yaw is instroduced, the strong "dihedral effect" will roll the aircraft due to the lift increase on the wing into the wind. The increased-induced drag on the rising wing will yaw the aircraft in the opposite direction, reversing the coupled oscillations.
Process:
1.Airplane yaws to the right
2.The left wing (sweptback) is more direct to the wind, so it lifts (rolling to the right).
3.But the drag on the rising left wing will cause the plane to yaw to the left, reversing the roll too, producing oscillatory instability.
Oxford Aviation Book 13.Principles of Flight.Chapter 10.35.