Members of the Congressional Quiet Skies Caucus, composed of Congresspersons throughout the United States whose constituents are significantly impacted by aircraft noise, have expressed deep concern, in a letter of September 23, 2020, to the Federal Aviation Administration (“FAA”) about the inadequacy of the FAA’s statutorily mandated evaluation of “alternative metrics to the current average day-night level [“DNL”] standard, such as the use of actual noise sampling and other methods, to address community airplane noise concerns.” See FAA Reauthorization Act of 2018, P.L. 115-254, §§ 173, 188 (“Report”). Caucus members catalogue a variety of insufficiencies.

First, Caucus Members found that the Report fails to evaluate well-respected and widely used alternatives including the metric used in California, Community Noise Equivalent Level (“CNEL”); ISO 1996-1:2016, an internationally utilized standard; and the Day-Evening-Night Level (“DENL”) metric also used in Europe.

In addition, Congress Members fault the Report on the ground that it fails to analyze complaint data; lacks scientific analysis, such as that developed in an FAA funded 2019, Massachusetts Institute of Technology Research Project; or any guidance on when supplemental metrics might be used in flight procedure design decisions.

In short, Caucus Members conclude that “the congressional intent underpinning Sections 188 and 173 was to address the inadequacy of the DNL metric and nudge the FAA towards a more comprehensive measure,” although “[t]he report fails to understand that intent.” On that basis, Caucus Members “insist that the FAA return to the drawing board.” As set forth in more detail in the June 10, 2020 article in the Aviation and Airport Development Law Blog, referenced in footnote 1 to the letter from the Quiet Skies Caucus, it is probably unrealistic to anticipate that FAA will go back to the drawing board, as the conclusions reached in its Report are those favored by FAA’s Chief constituencies, airlines and airports, that benefit from the understatement of noise impacts resulting from the use of the DNL metric. Whether Congressional influence in the area will grow stronger, or wane, with the upcoming election, is yet to be seen. Stay tuned for Congress’ further reaction after November 3.