Fig. 10. Mean force vector (F_N) and resultant directional forces and moments. (A) Schematic illustrating the type of force vector modulation occurring during the downstroke. As downstroke deviation changes, there is a correlated modulation of force magnitude while force inclination remains relatively constant. Correlation between downstroke deviation and downstroke (B) mean force magnitude (R²=0.43), (C) mean force inclination (R²=0.02), (D) mean lift (blue; R²=0.54) and mean thrust (green; R²=0.13), and (E) mean roll (blue; R²=0.44) and mean yaw (green; R²=0.05). (F) Schematic illustrating primary type of variation in mean force vector during the upstroke. As downstroke deviation changes, force magnitude is relatively constant, but there is unexplained variation in force inclination. Correlation between downstroke deviation and upstroke (G) mean force magnitude (R²=0.16), (H) mean force inclination (R²=0.004), (I) mean thrust (green; R²=0.22) and mean lift (blue; R²=0.0001), and (J) mean yaw (green; R²=0.17) and mean roll (blue; R²=0.001). The direction of the roll and yaw moments in E and J differ depending on whether they are generated by the left or right wing. For the left wing, positive roll is a right side down roll, and positive yaw is a yaw to the right. For the right wing, positive roll is a left side down roll, and positive yaw is a yaw to the left.