Flight Performance of a Dragonfly

Abstract

The dragonfly, Anaxparthenope Julius (Brauer) was observed in free flight, and a theoretical analysis of flight performance at various speeds was carried out. The variation with time of forces and moments acting on wings and body in steady trimmed flight was calculated by the local circulation method. Measures of flight performance, such as top speed, cruising speed and maximum endurance speed, were estimated from a necessary power curve required in steady flight and from the estimated available power. The results show that without using any novel unsteady aerodynamic force generated by a separated flow over the wings, the dragonfly can make steady trimmed flight at various flight speeds, from hovering to top speed.