Aerodynamic Capabilities of Flies, as Revealed by a New Technique

SUMMARY Forces and torques exerted by fixed flying Calliphora erythrocephala were monitored with strain gauges. Calliphora was shown to have independent control of all possible parameters of motion (lift, thrust, side-slip, roll, yaw, pitch). During voluntary manoeuvres, the fly modulated several or all of these parameters simultaneously. Modulations of certain parameters were strongly correlated. Possible applications of the strain gauge apparatus and limitations in the use of open-loop experiments for the study of flight behaviour are discussed.