Any good scientist knows insects should not be able to fly--their bodies are too fat for their tiny wings to lift. But an expert on aerodynamics and insect flight reported in Nature that he has solved the mystery and has come up with data that will fascinate aircraft designers.
Charles Ellington of the University of Leeds in Britain said insects create a complex pattern of vortices when they flutter their wings. Studying the hawk moth, Ellington mapped out this pattern for the first time. Each vortex acted to raise the insect up into the air, creating the extra lift necessary to overcome the insect's weight. Researchers tethered the moth with thread inside a small wind tunnel and blew smoke into it. They photographed the patterns made by the smoke as it passed over the wings of the frantically flapping moth.