FRIEDRICH PFEIFFER, Dr.-Ing., is Professor of Mechanics at Technische UniversitAt MA1/4nchen. Prior to joining the university in 1982, he spent 16 years as an engineer in the Space and Guided-Missile Division of Messerschmitt-BA3lkow-Blohm GmbH. He received his doctorate in aeronautics in 1965 from Technische Hochschule Darmstadt. CHRISTOPH GLOCKER, Dr.-Ing., received his degree from Technische UniversitAt MA1/4nchen in 1995. He is currently involved in postdoctoral studies.