The Noisy Dawn of the Jet Age Leo L. Beranek, Cambridge, Massachusetts Dr. Beranek received his Bach- A lifelong interest in music elor of Arts degree from Cornell led him to specialize on concert College in 1936 and his Doctor hall and opera house acoustics. of Science from Harvard Univer- Following trips to over 100 of sity in 1940. During World War II the world’s leading halls and he headed the Electro-Acoustic interviews of several hundred Laboratory at Harvard. He served conductors and music critics, he as Associate Professor of Com- wrote Concert Halls and Opera munications Engineering at MIT Houses: Music, Acoustics, and from 1947 to 1958. Architecture (Springer, 2004). He was co-founder of the fi rm, He has been consultant or cocon- Bolt Beranek and Newman of sultant on many concert halls, Cambridge, MA (started as a part- including the Tanglewood Music nership in 1948) and was its Shed in Western Massachusetts, President for 16 years, 1953 to the Meyerhoff Hall in Baltimore, 1969. During his time there, BBN the Aula Magna in Caracas, a con- became the largest acoustical cert hall, opera house and drama consulting fi rm in the world. One theater in the Tokyo Opera City of his efforts at BBN was putting together the group that invented complex and three other concert halls in Japan. the ARPANET which was the world’s fi rst packet-switched com- He has received numerous awards, including the President’s puter network and which operated under government fi nancing National Medal of Science, Gold Medals from the Acoustical So- from 1969 to 1989. BBN invented e-mail as we know it today. On ciety of America, the Audio Engineering Society and the American January 3, 1983, the ARPANET, having been split in two because Society of Mechanical Engineers, and the Silver Commemorative of its size, was joined by the TCP/IP protocol and became known Medal from the Society of French Language Acousticians. From as the Internet. 1989 to 1994, he served as President of the American Academy of The architectural acoustics part of BBN is now a separate compa- Arts and Sciences, and was honored in 2000 with their “Scholar- ny called Acentech, Inc., and the military acoustics and computer Patriot, Distinguished Service Award.” He is an Honorary Member activities are in a company called BBN Technologies. of the American Institute of Architects. The introduction of commercial jet aircraft operations in the in New York City. In attendance were Executive Director Austin United States was marked by controversy. This article reviews the Tobin, Matt Lukens, the Assistant Director of the Port Authority, politics and both objective and subjective noise measurements that and John Wiley, Director of Aviation, and one or two others in- ultimately permitted successful jet operations at U.S. airports. cluding a lawyer, and me. Tobin opened the discussion about as follows: “Pan American Airways has asked for permission to begin In the years between 1953 and 1958, one could travel by air jet aircraft operations from Idlewild airport in November 1958. coast-to-coast in a little more than eight hours on propeller-driven They will be fl ying a new jet passenger airplane, called the Boeing aircraft – all cross-country USA airline craft had four engines. 707. We must know how noisy it is. We already have a lawsuit in American Airlines used the Douglas Aircraft DC-7. United Airlines progress at our Newark airport brought on by residents who are fl ew both the DC-7 and the Boeing 377 Stratocruiser. Pan American complaining about the noise from today’s propeller airplanes. The boasted the DC-7C which fl ew overseas. TWA relied heavily on noise surrounding Idlewild must not be worse than that created the Lockheed Super G Constellation. Air travelers from the West by present large propeller-driven airplanes.” Coast to the East Coast often booked on the airline that scheduled Wiley carried on, “Several years ago, we told the airlines that a a few-minutes shorter trip. This period was followed, starting in jet plane must make no more noise than a large propeller airplane 1958, by the introduction of the Boeing 707, 4-jet-engine, aircraft on takeoffs and landings. Boeing claims that they have met this which made the trip from the West to East Coast in less than 6 requirement and their evidence is that the conventional sound level hours – today, a little over 5 hours. New York’s Idlewild Airport meter shows the same number of decibels of noise from the jet plane (JFK) was and is a must airport for all the major airline services. during fl yover as from a Super-Constellation propeller airplane. The question in the 1956-1958 period, was, “What conditions But we are worried, because we are getting reports that the 707 is will the Port of New York Authority place on jet aircraft wishing much noisier. In fact, we have already received threats that if the to use Idlewild?” noise around Idlewild increases, mothers with baby strollers will go on to the runways. We want you to set up a thorough program The Boeing 707 to investigate this problem so that we know what we’re up against Perhaps the largest contribution that Bolt Beranek and New- and what we should do about it.” man, Inc. made to the “welfare of mankind” was the company’s I accepted the project for BBN and said the fi rst thing that should assistance to the Port of New York Authority (PNYA), now the Port be done was for PNYA to arrange for Boeing to make fl yovers of the Authority of New York and New Jersey, in the late 1950s in regard airplane just as they planned to deliver it to Pan American and that to the fi rst fl ights of jet aircraft from New York International Airport we listen to the noise, with Tobin and Wiley present, and simultane- at Idlewild, now JFK, Airport. ously make measurements and recordings of the noise level. The fi rst PNYA/BBN meeting was held November 7, 1956, in The Boeing 707, while similar to the KC-135 military jet tanker, the offi ces of the PNYA, located at at 14th street and 8th Avenue was a completely different airplane. It originated from the Dash 80, a prototype designed and built entirely with Boeing funds with no interest or support from commercial or government customers. “The Noisy Dawn of the Jet Age” is taken from a chapter in an upcoming autobiography of Leo Beranek to be published by the MIT Press sometime It had no muffl ers. Our measuring equipment consisted of the lat- in 2007. Please visit http://mitpress.mit.edu for more information. est type of microphone and an excellent portable magnetic tape 94 SOUND AND VIBRATION/JANUARY 2007 www.SandV.com recorder. A few weeks after the New York meeting, Boeing fl ew the prototype 707 over us in Seattle at a height of 1000 ft, similar to the 120 height they would achieve on takeoff above the nearest houses at Idlewild. We were stunned – the noise was terrible, unbelievable. 115 Tobin, Wiley and I concurred that the noise level was completely unacceptable and they so reported to Boeing. The Boeing people Pa 110 2.5% m appeared devastated. How could the jet plane and the prop plane 10% measure the same on a sound level meter and yet one sounds so 105 25% much louder than the other? 50% The explanation for the difference in ‘noisiness’ created by the 100 75% two types of aircraft is that a propeller airplane has its loudest noise 90% in the low-frequency (low tones) range of 50 to 200 Hz, while that 95 Overall SPL, dB re 20 of the jet has its loudest noise in the high-frequency range of 500 97.5% to 2000 Hz. The human hearing mechanism is many times more 90 2.0 mi 3.0 mi sensitive to high frequency noise than to low frequency noise. The 2.5 mi 4.0 mi 5.0 mi 6.0 mi 7.0 mi 85 sound level meter ‘hears’ high and low frequencies equally. 10,000 20,000 30,000 40,000 After we arrived back in New York, I proposed a procedure. Distance from Start of Takeoff Roll, ft “BBN recently has employed one of the best experimental psy- Figure 1. New York Idlewild (JFK) airport typical outdoor sound pressure chologists in the country, Dr. Karl Kryter. We have one of the fi nest levels of DC-7 & 7B, DC-7C, 1049 & 1649 Super Constellation and DC-6B noise measuring crews with the latest equipment, headed by Mr. aircraft (7 kt headwind, 59° F). Each curve gives the percentage of propeller aircraft fl ights for which the peak overall sound pressure level equaled or Laymon Miller. If you authorize BBN to go ahead, the three of us exceeded the amount shown on the ordinate. The nearest residence was will be responsible for the whole project and we are prepared to in Howard Beach, 2.5 miles distant from the start of take-off roll. For the spend almost full time on it until completion.” 25% curve, the measured overall peak noise level at 2.5 miles from start of The overall proposed program was to determine the annoyance the take-off roll was 109 dB or more. Headwind & temperature corrections – for 0 kt headwind, add 2 dB; for 15 kt headwind, subtract 2 dB; for 100° that would be produced by jet aircraft in neighborhoods around F, add 3 dB.