4 Pm (Cookies and Coffee from 3:45 Pm)

Seminar Ray W. Herrick Labs., Hudelson Conference Room. (Building name on campus map: HERL. Main entrance on east side of building across the parking lot behind the round barn on Russell Street, on the south side of State Street.)

Thursday, 22nd February, 2007. 4 pm (Cookies and Coffee from 3:45 pm) From Sonic Booms to Sonic Puffs

Dr. Ken Plotkin, Chief Scientist, Wyle Laboratories, Arlington, VA

Abstract: Since the 1970s, commercial supersonic flight has been banned overland because of the negative impact that sonic booms from conventional supersonic aircraft have on structures and people. There is an understanding of the kind of sonic booms that could be acceptable, but technology that would achieve a "sonic puff" from a full scale supersonic airliner is far in the future. Recent advances in supersonic aircraft design have, however, shown that technology to build an acceptable smaller supersonic aircraft - a business jet - is within grasp. This seminar will include a brief history of sonic booms and an overview of the main elements of source and propagation models necessary to predict sonic boom signatures. The process of shaping a puff rather than a boom will be presented. There will be a discussion of the hurdles that are faced, particularly how it was proved that such aircraft are possible and how it can be shown that such booms would really be acceptable.

Biography: Dr. Kenneth J. Plotkin, Chief Scientist at Wyle Laboratories, is a recognized expert on sonic boom. He received his BS in Aerospace Engineering from the Polytechnic Institute of Brooklyn in 1965, and his PhD from Cornell University in 1971. His first involvement with sonic boom was as a graduate student at Cornell, where his thesis work was on the propagation of booms through turbulence. During his career at Wyle Laboratories, he extended his expertise to most aspects of sonic booms, including effects on people and structures. He has developed a number of aircraft and transportation noise models, including all of the sonic boom models used by the US DoD. He has served his time in the desert listening to and measuring booms. He was a key player in the recent DARPA/NASA Shaped Sonic Boom Demonstrator project that proved that sonic booms from aircraft can be reduced by proper shaping. In counterpoint, he was also part of the USAF "Have BEAR" project that taught fighter pilots how to generate focused superbooms. Dr. Plotkin has prepared the noise and sonic boom analysis sections of numerous Environmental Impact Statements. He is a Senior Member of the American Institute of Aeronautics and Astronautics, a Member of the Society of Automotive Engineers, and a Fellow of the Acoustical Society of America.