October 5, 2001
The intent of this lecture is to address past, current and projected USA applications of very high speed jet engines for space access and hypersonic atmospheric cruise. The content of the lecture is intended to relate these topics to a non-technical audience, so some details have been purposely omitted. The topics addressed in this lecture include brief discussions about what the term "hypersonic" means, what vehicle staging is and why it is needed, and how these two items relate to Professor Sanger's quest that originated in the early 1930's. The lecture will discuss the types of air breathing jet engines used to achieve hypersonic flight and why they are preferred over rocket motors for sustained endo-atmospheric flight and affordable space access. Recent and current international hypersonic programs and current and projected programs within the United States will be discussed. The lecture concludes with a projection of what the near future may hold for the development and application of hypersonic air breathing engines within the United States to both atmospheric flight and affordable space access.
Dr. Paul J. Waltrup received his B.S. (1967) and M.S. (1968) degrees from the University of Maryland and his Ph.D. (1971) from the Virginia Polytechnic Institute and State University, all in Aerospace Engineering. He joined the Applied Physics Laboratory in 1971 as a Post-Doctoral Fellow and became a Senior Staff Engineer a year later, specializing in subsonic and supersonic ramjet propulsion. He recently stepped down as Supervisor of the Aeronautical Science and Technology Group to devote his time to technology and program development and to staff mentoring. A member of the APL Principal Professional Staff, he is currently the Group Senior Engineer/Scientist. Dr. Waltrup has published over 100 technical papers and received a number of awards and citations for his technical contributions to supersonic combustion and hypersonic vehicle system concept development over nearly three decades. Most recently he was awarded the Eugen Sanger Medal (2000) from the DGLR in Germany, and the Bonarjuk Medal (1999) from the Russian Academy of Science. He has taught undergraduate and graduate courses at the University of Virginia Polytechnic Institute, and is currently a member of the Visiting Committee of the Mechanical Engineering Department at The Johns Hopkins University. He is an Associate Fellow of the AIAA and Editor of the Proceedings of the International Symposium on Air Breathing Engines (ISABE).