SWARTZ, S.M.*; STOCKWELL, E.F.: Wing architecture and maneuverability in bats: a 3-D kinematic approach

Both the flight capabilities and the wing structure of extant bats are diverse, and many studies have sought the morphological basis for bat flight performance, including maneuverability. Most analyses of the relationship between wing structure and flight maneuverability have selected descriptors of wing morphology based on the aerodynamics of fixed-wing aircraft. In particular, single values for wing area, wing loading, and aspect ratio, defined at an estimated mid-downstroke posture, have been employed as descriptors. Here, we suggest that flapping flight, particularly the ability to perform three-dimensionally complex maneuvers, can be better related to wing design by morphological and kinematic descriptors that account for the intrinsically dynamic and three-dimensional nature of flight. We employ three-dimensional kinematics of wild-caught bats in wind-tunnel and obstacle array flights to demonstrate the considerable variation in wing conformation that may be associated with given values of static mid-downstroke wing area, loading, and aspect ratio. We propose some descriptors of wing form based on three-dimensional kinematics, and suggest directions for future work.