Spring 2003 16.61AC3-4 Lateral modes Roll Damping-well damped As the plane rolls, the wing going down has an increased a (wind is effectively " coming up"more at the wing) Opposite effect for other wing There is a difference in the lift generated by both wings more on side going down The differential lift creates a moment that tends to restore the equ librium After a disturbance, the roll rate builds up exponentially until the restor ing moment balances the disturbing moment, and a steady roll is estab lished Disturbing rolling moment Restoring rolling moment D吓 Port Starboard Reduction in incidence Reduction in incidenceSpring 2003 16.61 AC 3–4 Lateral Modes Roll Damping - well damped. – As the plane rolls, the wing going down has an increased α (wind is effectively “coming up” more at the wing) – Opposite effect for other wing. – There is a difference in the lift generated by both wings → more on side going down – The differential lift creates a moment that tends to restore the equi￾librium – After a disturbance, the roll rate builds up exponentially until the restor￾ing moment balances the disturbing moment, and a steady roll is estab￾lished