Quieting the Boom: The Shaped Sonic Boom Demonstrator and the Quest for Quiet Supersonic Flight. By Lawrence Benson. Washington, D.C.: National Air and Space Administration, 2013. Photographs. Illustrations. Bibliography. Index. Pp. 388. $24.00 (Printed version) ISBN: 978-1-626-83-004-2
This book is part of NASA's Aeronautics Book Series and covers development and flight testing of its Shaped Sonic Boom Demonstrator (SSBD).
Benson begins by explaining the science behind the cause of the sonic phenomenon known as a sonic boom. He discusses early research, beginning with Austrian physicist-philosopher Ernst Mach, who explained the concept of sonic booms. Mach determined that the speed of sound was affected by the medium through which an object passes. In the case of flight, sound waves travel faster in warmer temperatures. In recognition of his work, the Mach number (the ratio between the speed of an object and the speed of sound) is named in his honor.
After briefly outlining the events surrounding Yeager's breaking the sound barrier in October 1947, Benson explains how sonic booms are created. He uses multiple diagrams to show both the sonic boom signature and shock cone. Having provided the reader with a basic understanding of sonic booms, Benson discusses in detail subsequent research into the phenomenon as well as the rise in sonic boom complaints submitted to the Air Force, more than 38,000 from 1956 to 1968.
Benson tackles the efforts of the newly formed NASA and its work with the supersonic transport (SST) concept. Coupled with NASA and USAF sonic-boom research of the late fifties and sixties, the FAA entered the sonic-boom-research arena by participating in tests to understand the effects of sonic booms on people, structures, and animals. As a result of concerns over the noise from SSTs, the FAA banned "commercial or civil aircraft from supersonic flight over the landmass or territorial waters of the United States if measurable overpressure would reach the surface" in 1973. With...