Fig. 3. Aerodynamic forces and torques during free hovering flight. (A–C) Translational forces over the course of the stroke cycle (abscissa). Red and blue traces show the forces generated by the right and left wing, respectively. The total force generated by the wings is shown in black, together with the S.D. (gray shaded area). The mean force over the duration of a stroke cycle is shown as a red dot on the ordinate. (A) Vertical force component, (B) forward thrust, (C) sideways thrust. (D–F) Torques. The same notation is used as in A–C. (D) Yaw torque, (E) roll torque, (F) pitch torque.