Posts Tagged ‘aviation noise’

Stage 5 Aircraft Noise Standards Approved in US – What does it mean for airports?

Wednesday, October 25th, 2017

By Jessica L. Cohen

On October 4, 2017, the Federal Register published a new noise standard for newly certified large airplanes.[1]  The noise standard, Stage 5, applies to large jets with a Maximum Takeoff Weight (MTOW) greater than or equal to 55,000 kg manufactured after December 31, 2017. Jets with a MTOW of less than 55,000 kg will need to adopt this standard by December 31, 2020. This is in correlation with the ICAO Chapter 14 noise standard, adopted July 14, 2014, for the purpose of ensuring efficiency for aircraft manufacturers in certifying their aircraft. In short, Chapter 14 and Stage 5 include the same requirements in their standard to reduce any extraneous cost or effort by requiring aircraft manufacturers to comply with two separate standards.[2]


Figure 1: EASA Certified Aircraft Noise Levels vs Chapter 3 Limit Source: HMMH modified EASA jet aeroplanes noise database (Issue 24 of 10/12/2015), January 22, 2016; updated March 2017


The new Stage 5 standard requires a cumulative reduction of 7 EPNdB (Effective Perceived Noise Level, in decibels) from Stage 4 standards, which correlate to ICAO’s Chapter 4 standards. Chapter 4 or Stage 4 standards, adopted in 2006, required a cumulative reduction of 10 EPNdB from the Chapter 3 limit. Therefore, Stage 5 compliant aircraft require a cumulative reduction of 17 EPNdB from the Chapter 3 limit. Figure 1 shows the different aircraft Stages versus the Chapter 3 (Stage 3) limit as well as some of the different aircraft types that fall into each Stage’s noise standard currently. Table 1 (below)  provides contextual information regarding the labels shown in Figure 1 (above).


Table 1: Aircraft categories as defined by ICAO/CAEP independent experts (IE)


For Stage 4 and Stage 5 requirements, the calculation of noise margins involves utilizing microphone locations at three places, which correspond to Chapter 3 noise limits. The cumulative result of subtracting the measured noise levels at three microphone locations from the limits determines whether an aircraft meets Stage 5 requirements.


Table 2: Analysis of Number of Jet Aircraft with a MTOW greater than 55,000 kg, Manufacturers, and Stage 5 Compliance Source: EASA, June 2017,


As Figure 1 shows, many aircraft currently in operation already meet Stage 5 requirements. Table 2 shows aircraft with a MTOW of greater than or equal to 55,000 kg, where future iterations of the aircraft types produced by these manufacturers will need to meet the Stage 5 noise standard beginning on December 31, 2017. Currently, approximately one third of these aircraft meet the Stage 5 noise standard and their manufacturers are Airbus and Boeing.


Figure 2: Summary of Stage 5 Noise Standard Compliance by Manufacturer and Number of Aircraft Types Source: EASA, June 2017,


Figure 2 (above) shows the number of aircraft types by each manufacturer that meet the Stage 5 noise standard currently, displaying whether all, the majority, a partial amount, a minimal amount, or none of that registered aircraft of meet the standard. Figure 3 below breaks this information down by aircraft type.


Figure 3: Stage 5 Noise Standard Compliance by Aircraft Type and Manufacture for Jet Aircraft with a MTOW of greater than or equal to 55,000 kg Source: EASA, June 2017,

[1] The Stage 5 Noise Standard was originally proposed by the FAA on January 14, 2016.


BTS Releases National Transportation Noise Map

Thursday, March 23rd, 2017

by Mary Ellen Eagan


The U.S. Department of Transportation’s Bureau of Transportation Statistics’ (BTS) initial National Transportation Noise Map was released earlier this week.  It shows that more than 97 percent of the U.S. population has the potential to be exposed to noise from aviation and Interstate highways at levels above below 50 decibels (roughly comparable to the noise level of a humming refrigerator).  A much smaller segment of the U.S. resident population has the potential to be exposed to higher levels of aviation and Interstate highway noise. Less than one-tenth of a percent of the population could potentially experience noise levels of 80 decibels or more, equivalent to the noise level of a garbage disposal.

The purpose of the noise map is to facilitate the tracking of trends in transportation-related noise, by mode, and collectively for multiple transportation modes. The data allow viewing the national picture of potential exposure to aviation and highway noise. The data also allow viewing of the potential exposure at the state or county level.

The National Transportation Noise Map will be an addition to the National Transportation Atlas Database (NTAD), a set of nationwide geographic databases of transportation facilities, networks, and associated infrastructure available from the BTS Geospatial Data Catalog. The layers will be updated on an annual basis, and future versions of the National Transportation Noise Map are envisioned to include additional transportation noise sources, such as rail and maritime.

The BTS map contains aircraft and road noise inventory data provided as web map services (WMS) for use with Geographic Information Systems (GIS), computer programs that can store, analyze, and present spatial or geographic data.

The mapping was developed by the DOT’s Volpe Center, using data sources from the Federal Aviation Administration (FAA) and Federal Highway Administration (FHWA) to create a comprehensive map of noise levels. The FAA’s Aviation Environmental Design Tool was used to model the average number of daily flight operations from airports across the country, excluding airports with exclusively military operations. To determine daily road noise data, algorithms from the FHWA’s Traffic Noise Model were used in conjunction with data from the Highway Performance Monitoring System to obtain the average daily noise levels for automobiles, medium trucks, and heavy trucks. The acoustics modeling used in developing these noise layers uses conservative, simplified methods, and only considers transportation noise (no other ambient noise sources). Documentation on the modeling assumptions is available at The noise data in the layers should be used for the purpose of tracking trends, not for assessing impacts. This data release represents the first year of data that can be used to analyze future trends.

So why are you complaining?

Wednesday, June 15th, 2016

by Nick Miller

S'Martin- S'Mararten

Maybe one person’s noise is another person’s music. Train horns in the distance can have a kind of nostalgic sound, but people who live near a grade crossing may not think so. (Try a room on the back side of the Hampton Inn San Diego – Downtown. You might take your earplugs.) Find any newspaper article on the Internet about aircraft noise complaints, check the comments and you’ll find things like “These folks should have known they are buying near an airport,” or considerably snarkier. Which might be a reasonable remark except even knowing doesn’t translate to a real awareness of what living with loud aircraft overflights day-after-day is really like. Of course, what realtor or home owner is going to try to alert the prospective buyer to the reality of life near an airport?

Quite a few airports require that home buyers receive some sort of disclosure statement, but all the ones I know about are presented at the closing. A little late, don’t you think? The only possibly effective method I know of is attempted by DFW airport. They try to get realtors to send in home buyers, and DFW shows them large displays of where aircraft fly. Much better, I think, than telling the buyer their house is in a noise zone or is within some decibel value of a noise contour. Who’s going to understand that?

I feel quite certain that most people who buy a home in the near vicinity of a commercial air carrier airport (say within 1 to 5 miles, depending on specific location and the level of operations at the airport) are unaware of what it can be like to live there day-after-day, night-after-night. I find it quite interesting, however, that there is a predominant meme that posits house prices reflect the acceptability of aircraft noise (hedonic pricing method). In other words, people pay less for such homes because they discount the price since they will have to live with the noise. Using hedonic pricing assumes that the buyer decides what to pay because he knows what he’s buying. That’s fine for buying a 60-inch flat screen TV to replace a 20-inch flat screen. But I think it’s an inaccurate means of assigning a cost to noise, or “monetizing” aircraft noise so that it can be compared with other costs (e.g. air quality health effects) or benefits (e.g. accessibility to transportation) of living near an airport. Studies seem generally to show a reduction in house price of 10% to 12% per 10 dB increase in aircraft noise, beginning at some identified lower level where there is an assumed no effect of aircraft noise.

But does this method really reflect the “cost” of noise? Some argue that noise is a quality of life issue upon which no price can be placed – a problem common to many amenities, such as low crime rates, clean streets or green spaces. Another way of thinking about the cost of noise, if we must, is how community dislike of noise affects decision-making about airports. Think about the many years (decades even) that it takes to propose, approve, design and build a new runway or a runway lengthening. What are the costs of the many studies reported as drafts, revisions, and revisions of revisions and associated public meetings, to say nothing of the costs of delayed construction and travel delays due to insufficient air travel capacity?

Finally, here’s an incident I recall reading about, but can’t verify for certain. Someone living in Northeast Harbor, ME, didn’t like the sound he could hear of the local sewage treatment plant. He asked the town if they could quiet it, getting the reply that they didn’t have the money to modernize it. So he donated, I believe, $60,000 to help the town pay for the quieting. Whether accurately remembered or not, I believe the substance is correct, and this story suggests to me a possible short-coming of asking people how much they would be willing to pay for less noise. The answer probably depends on what resources they have available.

HMMH Fall Tour 2015: On the Road Again

Friday, November 13th, 2015

by Mary Ellen Eagan

I’ve been on the road this fall at conferences – a whole lot of air miles, too many hotels, chicken lunches, and name tags (someday these will be designed for wearing on something other than a suit jacket lapel), but lots of great discussions, more than a few cocktails with good friends, and many laughs along the way. Some common themes emerged; here’s a recap of my highlights/takeaways:


Air Transport Action Group (ATAG) Global Sustainability Aviation Summit (Geneva)

At ATAG, ACI and Canso jointly released a document entitled Managing the Impacts of Aviation Noise, which provides a concise summary of airport noise issues, strategies for mitigation, and an extensive series of case studies. On community engagement, the report recommends following guidance issued in Eurocontrol’s Collaborative Environmental Management (CEM). One key difference between the European approach and ours is that the airport is at the center of the discussion. I am pleased to have contributed to the document.



ACI World Environment Standing Committee (Geneva)

Australia has seen good success in improving relations by having a very engaged and completely independent Aircraft Noise Ombudsman, who serves as a neutral party facilitating discussion of noise abatement alternatives, and educating the public using language that is not jargon. The Australians also provide guidance to airports (and others) on how to properly address complaints. And Canada recently released an Airspace Change Communications and Consultation Protocol for engaging communities and other stakeholders in discussion of proposed airspace changes. It, too, puts airports at the center of the discussion.



ACI-NA Annual Conference and Environmental Affairs Seminar (Long Beach)

My presentation at ACI focused on the concept of social license to operate (SLO), which originated in the mining industry. The premise of SLO is straightforward: owners of businesses and other enterprises that generate negative externalities must secure permission from stakeholders in order to grow – sometimes even to operate. And that permission is earned (not simply granted), by engaging stakeholders in a relationship that evolves from acceptance to trust. As shown in the illustration below from Social License institute, deteriorating levels of trust can lead to active political engagement and protest, as we’ve recently seen with the No Fly movement.


EFCG CEO Conference (New York)

This annual gathering of almost 300 CEO’s of firms in the A&E industry provides great perspective on the state of the industry, trends in financial results and other industry benchmarks, and an opportunity for firm leaders to share experiences on all kinds of issues facing our industry, including talent shortages, ownership transition models, and implications of new business models, technologies, and regulations. My favorite moment of the conference was my realization – during a fancy dinner at the Harvard Club – that the nine other CEO’s I was dining with were more interested in talking about their pets than their businesses. CEOs are people, too.



AAAE Basics of Airport Law Conference (Washington)

John Putnam (KKR) and I provided a session on emerging noise issues. Much of that discussion focused on PBN issues, the challenges posed by NEPA requirements in evaluating PBN procedures (not only at individual airports, but on a metroplex scale), and implications of FAA Reauthorization on airport noise issues.



ACC Annual Conference (Newport Beach)

There was much discussion at the Annual Meeting on the need to engage politically in conversations about airport development. ACC President TJ Schultz’s knowledge and insight into FAA funding and other political realities provides ACC member firms (especially small ones like HMMH) with context for making strategic decisions. I am honored to have been elected incoming Secretary/Treasurer for 2016, and look forward to serving on the ACC Executive Board with Don Bergin and Roddy Boggus.



ACI-NA Marketing and Communications Conference (Nashville)

ACI-NA’s Marketing and Communications conference held a session on airport noise. This is very exciting to me because the longer I’m in this business, the more I’m convinced that a good deal of airport noise issues can be addressed by better communication. I’ve come to this for several reasons: (1) first, we know that only about 30% of people’s annoyance to aircraft noise can be attributed to the noise level – that leaves a lot of opportunity for using “non-acoustic” measures to address noise issues; (2) after 30+ years in this industry, I am positive that people don’t suddenly start complaining about aircraft noise unless there has been some change in their environment or their life: a new runway, a new procedure, a new home, a new job (and increasingly, retirement). Working with stakeholders to understand the reasons for those changes often goes a long way toward resolving annoyance – sometimes it can be addressed, but even when it can’t, folks generally are satisfied that they have been listened to and validated.

Bottom line: sometimes the best consulting one can offer is to listen.


Looking forward to a brief respite (though I’m presenting remotely to the Aircraft Noise Non-Acoustic Group (ANNA) in The UK on Thanksgiving – hopefully not messing up the turkey too badly in the process). Then back on the road again in December to wrap up the year at ACC/BAG Global Business Summit (London) and ACI/ACC Planning and NEPA Workshop (Washington).



New NBAA Noise Abatement Procedures Released

Monday, June 29th, 2015

by Robert C. Mentzer

On June 25th 2015, the National Business Aviation Association (NBAA) released an update to its recommended Noise Abatement Program (NAP).  Details of their announcement can be found here.  This was a complete repackaging of their program and related materials many of which have been in place for decades.  HMMH worked with NBAA to evaluate the noise footprints generated by the prior and updated procedures with several in-use business jet types.  HMMH also assisted NBAA with the development of language to describe and identify how these changes may affect airports.

NBAA’s updated Noise Abatement Program was developed with modern aircraft performance and air traffic control (ATC) requirements in mind. With this revision, NBAA continues to provide operators with guidance to reduce noise impacts that is suited to the current operating environment, as well as new tools for aircraft operators and airports to address the noise concerns of adjacent communities.

The updated program includes:

  • Noise abatement best practices for flight crews
  • Updates to NBAA’s “close-in” noise abatement departure procedure and approach and landing procedures
  • Noise abatement guidance for other aviation stakeholders, including airports and air traffic control facilities

The revised NAP retains the recommendations for the existing standard departure procedure, but includes a new option for high-density airports. The high-traffic option – which allows for a shorter thrust cutback area – may allow the procedure to be used at busy airports where it was not feasible before.  The new guidelines do not include the former “close-in” departure procedure, which was found to have no significant impact on noise reduction for today’s Stage 3 and 4 aircraft, which climb so fast that they reduce power while over airport property, reducing the benefit to communities outside the airport boundary.

Since the former “close-in” departure procedure has been eliminated and several airports recommend NBAA procedures, NBAA included the following page on their site to assist Airport operators understand the changes to the NAP: