Yaw-induced roll is a type of aerodynamic coupling. When an airplane is yawed in flight, a rolling moment is induced in the **same direction**, left or right. Rotation about an airplane's vertical axis causes one wing to move forward or "advance", and the other wing to move rearward or "retreat". This creates a speed differential between the wings; the advancing wing experiences an increased local airspeed, while the retreating wing experiences a decreased local airspeed. This speed differential produces a lift differential, and a rolling moment in the same direction that yaw was experienced. ![[A4NA yaw induced roll modified.png]] If the airplane remains in a sideslip condition, lateral stability design features (ie dihedral, sweepback, etc) and three-dimensional flow effects (spanwise flow, [[Airflow Blanketing#Fuselage-Wing Blanketing During Sideslip]]) will continue to produce a rolling moment in the **same direction** the airplane was yawed. For more information, see *Lateral Stability and Control* (pg. 294 to 300) and *Roll Coupling* (pg. 315 to 319) in *Aerodynamics for Naval Aviators*. # References - [[00-80T-80.pdf](https://www.faa.gov/sites/faa.gov/files/regulations_policies/handbooks_manuals/aviation/00-80T-80.pdf)]() ### By Kevin Sakson