Posts Tagged ‘aviation noise’

A “perfect storm” – Recent actions by all three branches of the federal government address more types of aircraft noise, and acknowledge that adverse effects extend beyond traditional noise contours.

Thursday, July 18th, 2013

by Ted Baldwin

Serious federal attention to aircraft noise began around 1960, largely in response to community concerns (okay, complaints) related to the introduction of early air carrier jets (“airliners”), in particular the Boeing 707 and Douglas DC-8.

For the past half century, the federal government has largely focused its attention on aircraft noise associated with succeeding generations of airline jets at commercial service airports.  General aviation (g.a.) airports, g.a. jets, propeller aircraft, and helicopters have been a secondary focus of attention to all branches of the federal government, as illustrated by the following examples:

  • Legislative branch:  Congress has focused on laws phasing out older noisier aircraft over 75,000 pounds, which largely represent air carrier jets.
  • Executive branch:  The FAA’s development of the Integrated Noise Model (INM) has largely focused on modeling air carrier jets, as exemplified by the database’s most extensive coverage for that category of aircraft, with increasing dependence on substitute modeling surrogates as aircraft weight decreases.
  • Judicial branch:  Legal decisions have largely accepted arguments that significant noise exposure and associated liability extend only to the 65 decibel (dB) Day-Night Average Sound Level (DNL) contour, on which g.a. aircraft and helicopters have relatively little effect;  typically the 65 DNL contour from these aircraft alone encompass little – if any – off-airport land.

To build on the “ocean” metaphor in the title of this posting, the airline jet noise “tide” is ebbing, largely as the result of federal legislation and FAA regulations that force the retirement of 14 C.F. R. Part 36 Stage 1 and 2 jets over 75,000 pounds, and require applications for new “type certification” to meet Stage 4 requirements.  Local noise abatement and land use compatibility programs have complemented these federal actions (and frequently benefited from federal funding and implementation support).

One potential federal response might be to declare “mission accomplished” on the noise front, and turn the focus to areas where the tide is rising – both literally and figuratively; e.g., emissions-related contributions to climate change, which appear to be associated with storms that threaten coastal airports and result in operational delays at airports at all elevations.

However, recent actions show that the federal government is taking a different approach, and turning its focus to previously neglected – or at least lower-profile – noise issues associated with g.a. airports, g.a., jets, and even helicopters.  Again, this “changing tide” is reflected across the board at the federal level:

  • Legislative branch:  In the “FAA Modernization and Reform Act of 2012,” Congress prohibited, after December 31, 2015, regular operation in the contiguous 48 states of civil aircraft weighing 75,000 pounds or less that do not meet Stage 3 noise levels.  See
  • Executive branch:  As summarized in its “Aviation Noise Impacts Research Roadmap,” the FAA is supporting a number of initiatives recognizing a broader range of noise issues, such as the accuracy of the INM for modeling g.a. aircraft and enhanced modeling of taxiway noise.
  • Executive Branch:  In a more applied case, the FAA adopted a final rule on July 6, 2012 that requires helicopter pilots to use the North Shore Helicopter Route when operating along the north shore of Long Island, New York.  The purpose of the rule is to “protect and enhance public welfare by maximizing utilization of the existing route flown by helicopter traffic one mile off the north shore of Long Island and thereby reducing helicopter overflights and attendant noise disturbance over nearby communities.”  (see
  • Judicial branch:  In a recent opinion that denied a petition by the Helicopter Association International (HAI) for judicial review of the preceding mandatory helicopter route, the U.S. Court of Appeals for the District of Columbia Circuit supported the other executive branches in their focus on lower levels of noise exposure related to operations by non-airline aircraft.  (see$file/12-1335-1446255.pdf)

It should be noted that the Long Island helicopter route rule addressed in the preceding two bullets was initiated by two federal legislators representing Long Island residents – Senator Charles Schumer and Representative Tim Bishop – who conducted a meeting in October 2007 with the FAA, local helicopter operators, and airport proprietors to specifically address noise complaints stemming from helicopter operations along the north shore of Long Island.  While only the executive and judicial branches took formal action, the process involved significant input by these legislators as well.

The mandatory helicopter route is particularly significant because it represents divergence from several prior federal positions related to the longstanding “line in the sand” that the federal government has drawn at the 65 decibel (dB) Day-Night Average Sound Level (DNL) contour: 

  • First, it reflects major divergence from the prior federal position that reduction of sensitive land uses exposed to noise above 65 dB DNL was a de facto prerequisite for approval and support of noise abatement or compatible land use actions.  In its brief responding to the HAI petition, the FAA acknowledged that the route would not produce any benefit at or above this level of exposure, and noted that it “has authority to act without first demonstrating that a specific noise level has been exceeded.”  Furthermore, the FAA brief cited the “Long Island North Shore Helicopter Route Environmental Study,” which it had tasked the John A. Volpe National Transportation Systems Center to conduct.  That study concluded that prior to the adoption of the mandatory route, no residential population along the route was exposed to noise above 45 dB DNL, even on busy holiday weekends (e.g., around Memorial Day and July 4th, 2011).
  • Second, it reflected the first time – of which this author is aware – that the FAA relied on complaints as a fully sufficient basis for adoption of a formal noise abatement procedure.  In perhaps its most blunt statement regarding complaints, the FAA brief responding to the HAI petition stated “[w]hen people take the time to complain about helicopter noise to the FAA and their elected officials, there is a noise problem.”

The FAA’s justification for and defense of adopting a mandatory noise abatement rule based on noise complaints and with open acknowledgement that the benefit outside the 65 dB DNL contour by a 20dB margin is an extraordinary divergence from decades of FAA policy and decisions regarding noise compatibility actions.  As just one example, readers may recall that in its determination that the Naples (FL) Airport Authority (NAA) adoption of a ban on Stage 2 operations “was unreasonable and unjustly discriminatory” and therefore in violation of federal law, in part because the “NAA’s use of complaints … does not support a finding that the Stage 2 ban is reasonable.”  (”Director’s Determination,” FAA Docket No. 16-01-15, March 10, 2003.)

These recent actions by all three branches of the federal government clearly acknowledge that aircraft noise impacts worthy of addressing in the most formal manner need not be justified by federal land use compatibility guidelines, are not limited to particularly noisy aircraft, and do not even require quantification in decibel-based terms.

While the applicability of these actions as precedents in addressing other noise concerns across the U.S. will undoubtedly be the topic of vigorous debate for some time, airport noise stakeholders – including aircraft operators, pilots, airport proprietors, state and local government land use jurisdictions, airport neighbors, and others – should follow the federal lead in taking a fresh look at creative bases for demonstrating benefits and considering – or reconsidering – the full spectrum of noise abatement and compatible land use measures that might be applied to aircraft noise sources of local concern. 

A Better Way to Compare Aircraft Noise and Emissions?

Wednesday, April 6th, 2011

by Nick Miller

The World Health Organization (WHO) has recently published “Burden of disease from environmental noise, Quantification of healthy life years lost in Europe.” The title sparked my interest because there is an on-going effort in the U.S. to quantify and compare the relative adverse effects on society caused by aviation noise and aviation produced air pollutants. For the primary air pollutants, current U.S. work translates benefits of reductions to such things as reductions in premature mortality and in chronic bronchitis, to which dollar benefits are assigned. For noise, the Noise Depreciation Index (NDI) reveals how many dollars in housing prices are gained by reducing noise. 

I’ve always been troubled by this comparison of dollars of house price saved versus dollars of lives saved –not because I doubt either the calculations or assigning dollars to a life, which is standard in many cost benefit analyses. But my opinion, shared I think by many who deal with community reactions to aircraft noise, is that house prices really don’t reflect the adverse noise effects of living near a busy airport. For one thing, realtors and sellers go out of their way to down-play the aircraft noise issue.

Well, whether or not we want to pursue that debate, here come the Europeans and WHO, with “disability-adjusted life-years” (DALYs) as a method for quantifying any environmental health effect, and a report specifically addressing noise. Though my hopes for enlightenment about aircraft noise were immediately dashed when I learned that this report deals almost exclusively with the effects of road traffic noise, the DALY method may eventually have some use for comparison of aviation noise and emissions effects.

So how do we compute DALYs? Basically it’s the sum of years of life lost (e.g., premature mortality) and years lived with disability, or years of healthy life lost (e.g., suffering chronic bronchitis). The noise produced disabilities the WHO report examines are cardiovascular disease, cognitive impairment in children, sleep disturbance, tinnitus and annoyance. These are all adverse health effects consistent with the WHO definition of health as being “a state of complete physical, mental and social well-being.”

Computation of DALYs requires knowledge of the number of people exposed to each level of noise, a dose-response relationship that gives percent of people affected at each level, the “disability weight,” DW, assigned to the effect (DW equals zero means no health effect, DW equals one, you die), and the number of years of living with the disability or years of life lost. Obviously, many assumptions are required, but I like the way the large number of assembled subject area experts synthesized their knowledge and the research literature results to quantify each variable and calculate the DALYs for each health effect. 

What most struck me, was the number of experts (41 are listed) who participated in developing the report. In contrast, current U.S. efforts have required that many people come up to speed on the effects of aircraft noise on people, working with an additional very few who had actually worked in the field of aircraft noise effects. (Three cheers to the FAA for bringing in experts from outside the U.S. to assist with development of the Aviation Noise Impacts Roadmap.) To be clear, those who had to learn, were already experts, many in acoustics, just not in aviation noise and its effects.

In some ways, how sad. In the 1970’s the U.S. lead the world in developing the knowledge needed to formulate a national policy on noise and noise control. But those efforts all stopped short in the early 1980’s. Hence, most of those with expertise have retired and no new blood added for these three decades.

Now that we are concerned about how we can expand the U.S. air transport system, change airspace use, add runways, and increase the use of under-utilized airports, recognition has come that we better understand what the noise and air quality effects will be on society. Let’s hope that we can develop enough understanding to provide the aviation decision-makers with the information they need for science based noise and emissions policy. Perhaps a bit more of looking to research results gathered outside the U.S. would benefit our efforts.