A Guide to U.S. Aircraft Regulatory Policy
Sanford Fidell, Vincent Mestre
Springer, (2020), 144 pp., hardbound, 109
USD, ISBN 9783030399078
This volume provides a concise chronological discussion of the history of US Aircraft noise regulations, up to and including the 1996 Revocation of the FAA Charter to promote civil aviation and the eventual FAA Act of 2018 and its potential influence on future aircraft noise regulations.
The book also provides a handy review of several closely related topics of interest. These include a review of the effects on individuals and communities of aircraft and airport noise (a topic for which Dr. Fidell is especially well known, and easily the most detailed chapter of the book). Other less rigorous chapters include aircraft noise measurement and modeling, airport land use planning and other airport noise mitigation strategies, and potential future changes to airport noise policy.
I did find the discussion of related topics to be useful and easy to follow for someone who is not a dedicated aviation noise specialist. However, I think that one additional topic that might have been useful to include would be a comparative analysis between US aviation policy and aviation noise policy around the world. For example, the European Union is known to be much more progressive in terms of noise control requirements for everything from consumer products to public projects. It would have been interesting to better understand how their aviation noise policies differ from those in the US.
Paul Burge, INCE Bd. Cert.
Why You Hear What You Hear: An Experiential Approach to Sound, Music and Psychoacoustics Eric J. Heller
Princeton University Press, Princeton,
NJ, USA (2013), 590 pp., Hardbound,
120 USD, ISBN 978-0-691-14859-5
There are numerous proofs of the Pythagorean theorem. Euclid provides one of the more interesting in his Elements where he uses only the geometry axioms he originally proposed. No algebra or trigonometry is needed, and the proof is remarkable because he gets there with a limited set of tools.
I appreciate Eric Heller’s Why You Hear What You Hear: An Experiential Approach to Sound, Music, and Psychoacoustics in much the same way. Heller goes about introducing the science of acoustics with a substantial handicap. Namely, calculus and differential equations are not welcome. Yet, Heller’s accomplishment is more impressive because he teaches with a set of limited mathematical tools. Heller compensates by using intuition and pulling in a similar phenomenon from fields outside acoustics where appropriate.
For instance, he explains impedance by aligning coins on a table. He gives the reader a conceptual understanding of autocorrelation by looking at temperature variations in Fairbanks. He describes vibrational modes using beads on a string. Along the way, Heller adds color to the discussions by mixing in historical anecdotes and quotes from well-known personages like Aristotle and Galileo. Even Napoleon plays a role in the history of acoustics. He recounts how the sound of bells was apparently heard by a ship 100 miles away at sea. That would seem to be impossible, but he goes on to show how it just might be plausible. In an amusing aside, he recounts how Sabine’s frequency in getting haircuts affected the reverberation time in his room and that one of his students surmised that hair might be a very good sound absorber.
I found the book as entertaining as it is informative. It is lucidly written, and the explanations and rudimentary mathematics can be understood by first-year undergraduates. The text is inviting because the volume is nicely illustrated and attractively laid out. Where illustrations are not enough, Heller relies on Paul Falstad’s physics applets that are freely available online. I was not aware of these applets prior to reading the book.
The book proceeds in a logical fashion by first discussing sound and wave propagation. It goes on to discuss some signal processing basics such as the Fourier transform and autocorrelation. Heller then describes sources of sound, vibrational modes, damping, and impulse response. Musical acoustics is next with chapters on wind instruments, the voice, violin, and piano. The book then moves on to discussing psychoacoustics where concepts like loudness, pitch perception, and timbre are explained. The book concludes with discussions on architectural acoustics and outdoor sound propagation.
The text can be used for a myriad of introductory level undergraduate courses in acoustics. However, I suspect that more experienced acousticians and noise control engineers will derive greater pleasure from it. There are surprises in every chapter. This is a book that makes acoustics interesting. Simply put, this is a fantastic book and is highly recommended.
David Herrin, Ph.D.
Professor, Mechanical Engineering,
The University of Kentucky