A Study on Optimal Pattern and Leader Shift of Formation Flight

Abstract

The aerodynamics of formation flight are studied by modeling wings using a horseshoe vortex. During flight in formation, wings receive upwash created by other wings, and the required power consequently decreases. The leading wing in a V formation receives less benefit, while in a U formation, the power reduction rate remains identical over all wings. In long-distance flights, the U formation is optimal. However, when the process of shifting the leader position in a V formation is considered, as is often observed in actual bird flocks in long-distance flights, the power reduction rates of all wings converge into the same value after several shifts. This value is identical to that of the U formation.