Guest Commentary: Now is your time to comment as FAA evaluates jet noise standards and mitigation
In 2017, the Federal Aviation Administration began to implement the NextGen Southern California Metroplex project, which modified commercial flight patterns to and from San Diego International Airport to optimize the efficiency of airspace use.
This led to a further concentration of flights, or “highways in the sky,” above several San Diego communities. Recent scientific research and objective data indicate that concentrated exposure to repetitive jet noise may cause serious medical harm, including cardiovascular events such as stroke and heart disease, along with cognitive processing problems such as decreased school performance for children, sleep disturbances and increased stress.
Similarly, small-particle jet emissions are linked to serious human diseases like respiratory ailments.
Dispersing jet noise and particle emissions is an acknowledged antidote to concentration and is defined as “the process of introducing track variability by changing aircraft lateral position enough to spread out repetitive and intrusive noise events experienced by people living under highly concentrated flight paths” (UC Davis Aviation Noise and Emissions Symposium, February 2021).
This is an update on recent developments regarding the efforts to reduce commercial jet noise over impacted San Diego communities.
Don Scata, the FAA’s director of noise research and policy, gave the keynote address at the recent Air Noise and Emissions Symposium in April. He acknowledged that the FAA received many more noise complaints after it rolled out the NextGen concentrated flight paths nationwide. He noted the significant noise impact on “flight corridor communities” and that the FAA’s recent Neighborhood Environmental Survey reported a significant increase in reported annoyance complaints.
Scata announced that the FAA is open to considering additional metrics to measure noise levels and reassess thresholds, including modifying the level at which the FAA considers noise to be “normally compatible” or of “insignificant impact.”
A key question is how to measure the impact of aircraft noise on residents and communities. The FAA has traditionally used a decibel threshold, but recent research suggests that measuring the frequency of noise events is a more accurate metric of human annoyance, stress and resulting health consequences. While one overflight at 65 decibels may not bother you, 10 overflights in 30 minutes is another story.
Noise experts recommend that a standard that measures noise repetition and frequency, or the “N above” standard, be used, i.e., assessing the number of noise “doses” above a threshold after which noise becomes a significant stressor.
To that end, the FAA recently opened a public comment period on its national Noise Policy Review. The NPR will evaluate:
• Whether the current use of the “day-night average sound level” (DNL) should be the primary noise metric for assessing cumulative aircraft noise exposure
• Whether and how alternative noise metrics may be used in place of or in addition to DNL
• The community’s understanding of noise impacts and how to better respond to aviation noise concerns
• The findings of ongoing noise research and more
The FAA is holding webinars this month via Zoom, and the public comment period closes July 31.
The remaining webinars are from 3 to 5 p.m. PT Thursday, May 18; 6-8 p.m. Tuesday, May 23; and 1-3 p.m. Thursday, May 25. For more information, visit faa.gov/noisepolicyreview.
Quiet Skies La Jolla will be providing comments on the Noise Policy Review. For updates, visit quietskieslajolla.org.
We urge all affected areas of San Diego to submit comments by the July 31 deadline and that the San Diego County Regional Airport Authority sponsor and facilitate round-table meetings to encourage a unified voice from San Diego. We can achieve better results working together as a community.
Bird Rock way point
The Airport Noise Advisory Committee submitted a formal recommendation to the FAA to mitigate nighttime aircraft noise by implementing a “Bird Rock way point” that would take departing planes farther offshore during the hours of 10 to 11:30 p.m.
In April, the airport reported that the FAA declined to advance that proposal due to “operational and safety concerns.” As the FAA is the sole arbitrator of such changes, the proposal will not move forward.
Aviation Impacted Communities Alliance
After the FAA rolled out its NextGen navigation program in 2016-17, communities across the country united under the Quiet Skies organization and a congressional caucus, advocating for the FAA to roll back NextGen and/or mitigate the human health harms.
San Diego, Los Angeles, Palo Alto, Baltimore, Philadelphia, Lake Tahoe, Boston and many others have joined the 67 members of the Aviation Impacted Communities Alliance to pool resources, coordinate efforts and work at the national level for change.
In the past, community groups have acted individually to get noise issues addressed in FAA reauthorization bills. But now a large coalition of community groups is speaking to Congress with one voice.
AICA is lobbying on Capitol Hill for solutions to address noise in communities more than a mile from airports (that are not within the 65-decibel day-night average sound level contours), require the FAA to take advice from the National Academies of Science on human health impacts from commercial jet noise, and require the FAA to devise action plans to alleviate noise and address community concerns, among others.
No single solution will work for all airports because geography, traffic constraints and external factors will require local answers. Flight dispersion and making use of the Pacific Ocean, however, are winning concepts for the entire greater San Diego community and should be implemented at the San Diego airport.
How to fix what’s broken
The NextGen project concentrated departures and landings over tight corridors, resulting in repetitive noise exposures to previously quiet communities. Communities affected by the concentrated departure paths include Ocean Beach, Point Loma, Pacific Beach, Mission Beach and La Jolla, all of which are central to San Diego’s tourism interests.
These communities participated in a series of meetings and workshops with the goal of recommending noise abatement procedures to the FAA. Proposals were made to disperse noise across three departure tracks so that no single community or group of residents will bear a disproportionate burden of living under or adjacent to a flight path.
The communities failed to come to an agreement about where to locate the three recommended dispersed flight tracks. Although the dispersion proposal would have reduced noise for thousands of residents (mostly in Ocean Beach, Point Loma and Mission Beach), a slight shift in noise would have affected a dozen or so homes in Ocean Beach.
The airport declined to move forward without unanimity. However, the airport committed to reevaluate the dispersion proposal in 2026, and it is important that all San Diego communities collaborate and reach a consensus on a solution that provides a win for the entire region.
Dr. Matthew Price, Chris McCann and Anthony Stiegler are co-founders of Quiet Skies La Jolla.