Fig. 13. Non-dimensional angular velocity of pitching rotation and azimuthal rotation (A), lift coefficient C_L (B) and drag coefficient C_D (C) versus time during one cycle for three different values of the non-dimensional duration of wing rotation _r. Symmetrical rotation; mean lift coefficient (midstroke angle of attack _m was adjusted to make the mean lift equal to insect weight). _c, non-dimensional period of one flapping cycle; , non-dimensional time.