ABSTRACT
Wingbeat frequency ranges from a few beats per second in large butterflies to more than 1000 Hz in tiny Diptera. In addition to dragonflies, butterflies are also good gliders, especially Iphicides podalirus which glide for as long as 30 sec without a single wingbeat. The flight motor is located in the thorax which contains, besides other things, at least two and sometimes four functional types of flight muscles: the driving muscles which keep the wings beating and steering muscles which control the relatively fine steering movements of the oscillating wing system. The wing path is drawn out relative to a fixed external point because of geometrically adding the flight velocity. The analytical procedure just described for “stationary” flight is valid if it is possible to measure lift and thrust of all wing strips defined at consecutive time values during the total stroke cycle of an animal flying steadily and horizontally.
