Replay from 2015:NextGen Noise: RNP’s concentrated IMPACT may justify substantive change in FAA policies under a proper study

Share this article: FacebooktwitterlinkedinFacebooktwitterlinkedin

ARTICLE: Tired Of Noisy Days And Nights, South Shore Residents Challenge FAA

ARTICLE: FAA’s NextGen Noise Problem is Stirring Up Lots of Activism in the NYC Area

NextGen implementation is generating complaints

Does the precision of RNP change the Noise Perception



Aviation Noise is being heard and objected to in higher volumes than in the past. It is hard to quantify the level of negative reactions in the metrics of engineering measurement, but the qualitative response is hard to ignore.

noise dfw atl


⇒ Where are the complaints being registered?  As evidenced by the below two articles and numerous other reports, citizens in


  • Boston,
  • Charlotte,
  • Chicago,
  • New York,
  • Phoenix,
  • San Diego,
  • San Francisco,
  • Seattle
  • Washington, DC and
  • Other places


are vociferously making their objections known


⇒ What do these cities have in common? As shown by the FAA website on NextGen, all of these airports have implemented NextGen procedures.


⇒ What can be gleaned from looking at these noise patterns? There is both good news and bad news.


  • The environment on a macro basis is better off; because the generalized area of impact is significantly decreased.


  • There is also BAD NEWS on a micro basis; in that the precision of the RNP technology and implementation CONCENTRATES THE NOISE IN A SMALLER AREA. The residents in these areas may be experiencing doubling of their historic noise levels ( +10 points on the scale equals a doubling of the actual energy). Further the RNP addition to the noise may not reach the FAA’s long standing threshold of 65 dBA; so the NEPA review may find that this change does not preclude the implementation.


So the people living under these new HIGH TEC, GREENER flight patterns are told at the end of the FAA study that there will be “no significant impact”, a term of NEPA art, which certainly infuriate the effected citizens.


⇒What has Congress conjured up to address this situation? The elected representatives have proposed reopening the ATC review process; see FAA Community Accountability Act of 2015” (FCAA). First, it should be noted that Congress recently reduced the review requirement for the FAA in implementing NextGen flight patterns (H.R.658 — 112th Congress (2011-2012), the FAA Modernization and Reform Act of 2012 (FMRA)). There is little likelihood that there will be a different outcome under an enacted FCAA by


  • ordering the FAA to REconsider its previous determination
  • under the original NEPA standard,
  • adding an ombudsman,
  • placing the airport explicitly in the process and
  • little else.


What the Congress has failed to realize is that the average citizen noise group needs significant resources to do anything other than say NO to the FAA RNP proposal. They need more than a new process; they need technical expertise to offer acceptable options.


⇒What is the FAA doing? In a March 27,2015 letter from Administrator Huerta to a coalition of aviation associations, he announced an “ambitious project to update the scientific evidence of the relationship between aircraft noise exposure and its impact on communities around airports in today’s context of quieter aircraft, but with more aircraft operations than in the 1980s and1990s and heightened environment awareness.”  The letter noted that the study was specifically in response to implementation of PBN tracks. The precise nature of the FAA studied was outlined in the Administrator’s letter:

The data from such a loosely defined and gathered  study does not appear to determine the precise impacts of the RNP concentrated procedures and hardly seems to be compelling enough to justify any changes in the FAA’s historic standards. {Rather tellingly, the letter invites replies NOT to the FAA technical environmental staff, but its Congressional relations office.}


⇒What needs to be done? A detailed, thorough and comprehensive study of points within these noise-concentrated corridors should be commissioned and at a minimum, hard numbers (not just subjective consumer perceptions) should be studied, like:


  • the precise location of the residence (to measure distance from the flight track before and after RNP),
  • the average level of noise experienced in that location BEFORE RNP,
  • the date on which the respondent occupied the residence,
  • whether  there are other noise sources proximate to their residence and what are they
  • how the number assigned by the respondent in the survey compares to other noise sources, such as
    • motorcycles
    • crowd noise at athletic events—at peak, when music is playing, normal cheering
    • ambulances
    • concerts
  • the change between pre and post RNP normalized noise levels, as measured by the appropriate calibrated instruments, at all of the test points
  • the change between pre and post RNP perceived noise levels at all of the test sites.

While this noise assessment may take longer that the FAA’s phone survey of citizen perceptions, the results of a technical review are FAR MORE LIKELY TO JUSTIFY A SIGNIFICANT CHANGE IN POLICY.


Share this article: FacebooktwitterlinkedinFacebooktwitterlinkedin

2 Comments on "Replay from 2015:NextGen Noise: RNP’s concentrated IMPACT may justify substantive change in FAA policies under a proper study"

  1. Thank you, Author. It’s corrected! 3

  2. The purveyors of FAA wisdom always omit some simple facts: the refined flight tracks don’t tell the story of how often the flight route usage has increased. They also never take into account other parameters such as spacing (wake RECAT), altitude, thrust. It’s obvious to most that where the planes are flown is only part of the overall picture. How often the planes are flown, and how, needs to be considered.

    Only a 55 DNL contour constructed in the period before NextGen compared to 55 DNL contour after NextGen will tell the complete, cumulative, overall noise story.

    There is a way to settle it once and for all: input the raw ANOMS data from the 1998 LaGuardia noise contours back into the INM and construct contours out to 55 DNL for 1998. Do the same for 2003 and 2008, the next set of contours. Then compare to the current part 150 study which goes out to 55 DNL. The difference will be apparent. These old studies from 1998, 2003, and 2008 only went out to 65 DNL. Re-do the studies out to 55 DNL, then compare to the modern, post-NextGen part 150 study.

Leave a comment

Your email address will not be published.