Use and Function of a Leading Edge Flap on the Wings of Eagles

*† ‡ § In this paper we present video evidence of unsteady maneuvers in which leading edge feather deflections occur on the wings of an Eagle in free flight. High-speed video is used to analyze the use of these feathers in greater detail during landing sequences. The results suggest that the feathers are being used as a means to stabilize the wing during these unsteady maneuvers. A novel method of measuring wing profiles of a bird in free flight is outlined.