Meeting Abstract

S1-4.1  Jan. 5  Under Vogel's wing, my work takes off: Bugs, birds, books and Boeing ALEXANDER, D.E.; University of Kansas dalexander@ku.edu

One of my first courses as a graduate student at Duke University was Steven Vogelís biological fluid mechanics course, and about then he became my advisor. My background in oceanography, and enjoyment of building gadgets, made Vogelís lab very inviting. My first research project was on sand dollars, which taught me that marine field projects take much longer than terrestrial ones. My second project, on tunicate pumping, ended when a nearly identical study was published in the middle of my first field season. Sage advice from Steve turned me toward animal flight mechanics, which remains my major research interest. Several years ago, Steve suggested I consider writing for a general audience. This eventually led to me write a book, which I found very rewarding. I have continued writing, and am currently working on a comparison of the mechanics of airplane flight versus the mechanics of airplane flight. Although the physics of flying animals and flying machines are essentially the same, the mechanical and functional differences are numerous and obvious. The key difference that underlies most of the other differences is that of power sources: animals use muscles whereas airplanes use engines based on rotating machinery. Muscles dictate flapping for power, which in turn constrains animal wing structure. In contrast, engines for power simplify wing structure. Engines also follow completely different scaling relationships than muscles. Muscle specific power scales negatively with body mass and thus constrains size, but engine specific power is nearly independent of size and is not a significant constraint on increasing aircraft size. My appreciation of the fundamental nature of this power difference was partly inspired by Steveís discussions of the lack of wheels in biology and influenced by his description of humansí historical reliance on muscle power.