Aerodynamics and Control Aspects of Formation Flight for Induced Drag Savings

Reduction of the carbon emissions due to commercial aviation, and fuel efficiency in general, is a key challenge the aerospace community is attempting to tackle. Formation flight is one of the potential solutions, which involves considerable fuel reductions due to induced drag savings. The present paper presents a) an extensive survey of current literature on aerodynamic analysis of formation flight, both theoretical (analytical and numerical) and experimental (wind tunnel and flight tests); b) a brief discussion of the proposed automated control systems in previous studies; and c) a study of six symmetric formation configuration using the single horseshoe vortex wing model to determine the optimum formation geometry. The detailed review, not previously reported in literature, shows that formation flight is a relatively extensively researched topic, with promising theoretical and experimental results. Simulations of the symmetric geometries give some insight into induced velocities on any given aircraft within a formation with respect to changes in lateral and longitudinal spacings, but application of systematic optimisation techniques is recommended for conclusive results.