Wind effects on bounding flight

The effects of the wind on the energy expenditure of bounding flight and on the travelling speed are dealt with. For this purpose, a mathematical model of bounding flight in moving air is developed. Introducing an appropriate non-dimensionalization, results and findings of generally valid nature are derived. It is shown that bounding flight yields a flight mechanical advantage in headwinds when compared with continuous flapping flight. This is because the minimum energy expenditure is lower and the associated travelling speed is higher. The body lift in the bound phase has an advantageous influence. The effects of tailwinds yield less differences between bounding flight and continuous flapping flight.

► A mathematical model of bounding flight in moving air is developed.
► With non-dimensionalization and scaling, generally valid results are derived.
► Bounding flight is shown to be superior to continuous flapping flight in headwinds.
► The minimum energy expenditure is lower and the associated speed higher.