Fig. 12. Polar diagrams for real hawkmoth wings in steady translating flow and `pooled' model hawkmoth wings in revolution under `early' (upper grey line) and `steady' (lower grey line) conditions. Data for hawkmoth in translational flow are taken from Willmott and Ellington (1997c) for a Reynolds number of 5560, and ranges from -50 to 70° in 10° increments. C_h, horizontal force coefficient; C_v, vertical force coefficient; , geometric angle of attack.