Leading-Edge Vortex Lifts Swifts

  title={Leading-Edge Vortex Lifts Swifts},
  author={John J. Videler and Eize J. Stamhuis and G. David E. Povel},
  pages={1960 - 1962}
The current understanding of how birds fly must be revised, because birds use their hand-wings in an unconventional way to generate lift and drag. Physical models of a common swift wing in gliding posture with a 60° sweep of the sharp hand-wing leading edge were tested in a water tunnel. Interactions with the flow were measured quantitatively with digital particle image velocimetry at Reynolds numbers realistic for the gliding flight of a swift between 3750 and 37,500. The results show that… Expand
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