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AERODYNAMICISTS and biologists have long recognized the benefit of formation flight. Wieselsberger [1] was the first to attempt to quantify the aerodynamic advantages of formation flying. Using newly developed ideas from Prandtl’s lifting-line theory, he represented three birds in a diagonal formation using horseshoe vortices and showed a corresponding reduction in induced drag due to the influence of the bound and trailing vortices. Conceptually, formation flight can be understood by looking at the counter-rotating vortices generated by a finite wing. A second bird, properly positioned outboard of one of these vortices, benefits from the rising air of the upstream vortex and experiences a reduction in the power required to fly. Lissaman and Shollenberger [2] published theoretical results that predicted a flock of 25 birds has a 71% greater range than a single bird. For the last few decades, Hummel [3, 4] has …