Drafting (aerodynamics) - Vortex Surfing in Nature

Vortex Surfing in Nature

Cooperative fluid dynamics techniques like drafting are also found in nature. Flocks of geese and some other birds fly in a V formation because the wingtip vortices generated by the front bird will create up-wash circulations. The birds flying behind will receive lift force from these up-wash vortices. Thus other birds in the flock do not need to work as hard to achieve lift. Studies show that birds in a V formation place themselves roughly at the optimum distance predicted by simple aerodynamic theory. The theory behind this is the same as the one for the wings of an airplane in general. However it does not work quite the same way as drafting in racing. Birds fly in a flock for better lifting force whereas the race cars stay close for less total aerodynamic drag force.