Which of the following contributes to an increase in directional stability? Solution Correct option: C) Larger Vertical Stabilizer Directional stability is about normal axis and is maintained by the keel surface and the fin, yaw dampers (yawing) and controlled by the rudder. The vertical stabiliser gives the aircraft directional stability due to pendulum effect. Hope this helped you! Thank You So Much! Please Rate this answer as you wish.(\"Thumbs Up\") .