Save Our Skies East Bay

Voice for the East Bay to identify increased air traffic noise and implement solutions

FAQ

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  1. Why are so many people complaining about airplane noise?
  2. What is NextGen?
  3. Isn’t the extra noise due to the weather?
  4. How has NextGen changed where airplanes fly in the East Bay?
  5. Doesn’t NextGen save fuel?
  6. Doesn’t NextGen make planes more “on-time?”
  7. We live in a fairly urban area; shouldn’t we expect this noise as normal?
  8. What is “noise shifting?”
  9. What does “restore” the noise patterns mean?
  10. What does the FAA mean by “no significant (noise) impact?”
  11. What is a quieter, near idle descent?
  12. What is being done to address the airplane noise issues in the East Bay?
  13. What about a lawsuit?
  14. Why can’t all of the planes just fly over the Bay?
  15. What is the timeline to effect changes?
  16. How does the FAA measure and evaluate airplane noise flying overhead; and do their analyses accurately measure the experience of people below the flight paths?
  17. What is night time noise abatement, and why do I keep hearing really loud planes late at night?

  1. Why are so many people complaining about airplane noise?

Many communities in the East Bay have become painfully aware of an onslaught of air traffic over their homes, and they aren’t imagining it. The increased noise has nothing to do with weather, wind direction or increased holiday season air traffic. This is the new reality of the FAA’s Next Generation Air Transportation System (“NextGen”) that was introduced to the East Bay in 2015. Planes are now concentrated on a few “sky superhighways” in the Bay Area. Many communities, located miles from the airports, now experience planes flying lower, often less than 3,000 feet over homes, and more often, sometimes every 2 minutes.

The FAA calls these new sky superhighways, “tracks.” Prior to 2015, aircraft traffic in the East Bay was dispersed over wide flight areas, up to 6 miles wide, with much of that being over the Bay. NextGen concentrated all that traffic from both the Oakland and San Francisco Airports into a small number of narrow corridors mostly less that 2000 feet wide. The portion of airplane traffic that had flown over the Bay was shifted to now fly over residential areas. This meant that instead of sharing noise more equitably, a limited number of neighborhoods got slammed and now bear the brunt of all the noise.

A significant new NextGen approach procedure for planes arriving into Oakland Airport from the north has planes flying at lower altitudes while under power over the topographically highest part of the East Bay Hills. This procedure increased the roaring, thunderous, airplane noise to unprecedented levels over homes and neighborhoods that never experienced aircraft noise prior to this. Decibel ratings of well over 80dB have been recorded at homes. To make matters worse, the use of air brakes creates a loud, whining sounding like “bombs falling” and the low-frequency thunder rattles homes and  windows.
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  1. What is NextGen?

NextGen stands for “Next Generation Air Transportation System.” It’s an FAA program to shift the U.S. ground-based radar system with radio communication to guide and control air traffic to a satellite-based system – GPS. NextGen is being implemented in stages across the U.S. between 2012-2025 and is designed to “optimize air space.” In theory, it’s supposed to cut costs, save time, fuel and money, as well as curb traffic delays. The FAA claimed there would be “no significant noise impact” to those on the ground. Wherever NextGen has been implemented, the only noise outdoing the roar of airplanes is the dramatic increase in noise complaints from the hard hit communities who are now forced to live under the new, concentrated NextGen flight corridors.

It’s important to understand that it’s not NextGen as a whole that is the issue. NextGen goals are commendable, even according to many suffering under its thunderous noise impact. It’s the new, concentrated flight path locations, lower altitudes above homes, and flying procedures for planes arriving and departing our airports that are creating the negative noise impacts and complaints. These must be restored to echo the noise conditions communities grew and developed under. It’s also worthwhile noting these localized changes were not made to address safety issues.
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  1. Isn’t the extra noise due to the weather?

Unfortunately, no. If it was just the weather, we couldn’t mitigate that. Many have noted over the years that in certain windy conditions or stormy weather the planes get ‘louder.” In certain conditions called “reverse” or “southeast flow” wind conditions, planes need to land from the opposite direction than they do under normal, prevailing weather conditions. Physics is physics, and planes need to land “into the wind.” This means when reverse or southeast wind conditions exist, Bay Area air traffic lands and departs in the opposite direction of normal. This means, that traffic flying into SFO arrives over the East Bay Hills. SFO has a lot of traffic, so the East Bay Hills experience increased numbers of planes, flying low and loud during stormy weather.  This southeast or reverse flow direction of air traffic did not change with NextGen.

The Oakland Airport estimates that, on average, reverse flow conditions exist less than 10% of the time over the course of a year. The increased stormy weather during the 2016-2017 rainy season increased the number of days San Francisco Airport flights arrived over the East Bay Hills. After years of drought, it was a glaring change in air traffic. Interestingly, there can be reverse flow conditions at Oakland and not at San Francisco Airports and vice-versa, only adding to the complexity of Bay Area skies.
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  1. How has NextGen changed where airplanes fly in the East Bay?

This question is easiest to answer by looking at a graphic of how things changed:

(Montclair Flight Track Analyses, HMMH Inc., Technical Memorandum HMMH Project Number 302551.004, March 30, 2016)

This is a picture of how Oakland and San Francisco Airport flights were concentrated in the East Bay before and after the FAA’s NextGen program was implemented in 2015. It’s from a report the Oakland Airport commissioned to study the issue. The map on the left shows that planes were previously dispersed broadly (light yellow areas) over the East Bay. This dispersion more equitably spread airplane noise. The map on the right shows conditions after Nextgen was implemented and reveals how many areas had much of their overflying traffic eliminated (turned into a blue green color) and concentrated the traffic into tight corridors that slammed certain areas (the deep orange lines).

These maps clearly show how plane traffic was highly concentrated in limited areas and why some will say “huh? what noise?” and others hear an onslaught of planes. The deep orange color represents the highest aircraft concentration. It is easy to see how it affects very specific streets and neighborhoods that were not impacted like that prior to NextGen. The planes truly do fly in narrow corridors about 1500-2000 feet wide now as a result of NextGen. The resulting noise impact is not just your sensitive neighbor’s imagination.

This is not an issue of luddites against airplanes or airports. We all enjoy the freedom and goods that the airports provide, but the noisy downsides need to be shared more equitably and restored as much as possible to the pre NextGen patterns when complaints were minimal. Fixing the noise impact issues is not about being against NextGen or opposed to modernizing the way planes fly and in no way decreases safety or affects “on-time” performance – noise mitigation only addresses how the planes are “proceduralized” in the vicinity of an airport during landing and take-off.
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  1. Doesn’t NextGen save fuel?

While it’s true that a key goal of NextGen is to increase aircraft efficiency by reducing fuel consumption and exhaust emissions, the “success” of this goal is only achieved when one looks at an averaged national impact once planes are at altitude and headed towards their destination. Here are the ways NextGen can help save fuel:

  • NextGen uses a type of navigation called “Performance Based Navigation” or PBN for short. This basically uses GPS to get a plane where it needs to go. It allows planes to fly shorter, more direct flight paths than were possible with the longer, more zig-zag paths using ground based radar.
  • An Optimized Profile Descent (OPD) uses a computer to calculate an airplane’s descent into arrival using the most economical engine setting, at or near at idle. This minimizes and can even eliminate the need for a plane to “level-off” to slow itself down, which requires greater power (read more fuel!) and makes planes noisier. OPDs reduce fuel consumption, emissions and noise. They were touted as a huge advantage of NextGen.

This is all beneficial, and we support these aspects of NextGen. The big disconnect happens when planes are not in their high altitude flying patterns but are in the proceduralized arrivals and departures within about 30 miles of San Francisco and Oakland Airports. According to the FAA’s website, instead of saving fuel, there is an actual increase in fuel usage due to some poor procedures implemented under NextGen when planes are arriving and departing in the vicinity of airports. These same flying procedures also eliminate the ability of a plane to use quiet OPD descents too.

The advantages that NextGen could offer are thrown out the window when airplanes are required to fly the new NextGen Oakland Airport WNDSR arrival route down the East Bay Hills for planes arriving from the north. Along this WNDSR route, aircraft are required to fly under power for over 23 nautical miles at low altitudes. This is the noisiest, most polluting and fuel intensive way to get an airplane where it needs to go. In fact, the FAA estimates that the existing local NextGen procedures they implemented for the Bay Area will add up to an extra 10 Metric Tons of fuel used per year in their Environmental Assessment for the Northern California Metroplex (Section 5.7.3, Table 5.5). Helping solve the fuel issue is another aspect of NextGen that the Oakland Airport Noise Forum’s mitigation proposals sent to the FAA aim to do.
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  1. Doesn’t NextGen make planes more “on-time?”

NextGen can help improve communication, but when analyzing the numbers, it isn’t a player in keeping planes on-time. The top reasons for delays according to 2014 data from Aviation Week at MRO-Network.com are:

  • Extreme weather: 4.3% of delays
  • Airport Operations and Non-Extreme Weather: 23.5% of delays

    •       Even though airports have limited capacity and runways, they cannot control how many aircraft the airlines schedule, which can cause delays.

  • Air Carrier Delays Within the Airline’s Control: 30.2% of delays

    •       This includes delays due to aircraft maintenance, crew, cleaning, baggage loading and fueling.

    All of the above possibilities result in late arriving aircraft. A delay at one end triggers a ripple effect through the system, which results into the remaining 41.9% of the delays. NextGen can’t control these factors, therefore, it really has little effect on an airline’s on-time performance.
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    1. We live in a fairly urban area; shouldn’t we expect this noise as normal?

    Prior to NextGen, aircraft traffic was dispersed widely over the East Bay. As a result, noise was spread more equitably and complaints were few. Most of the East Bay experienced medium traffic levels, and we lived with it. Judging by the pre-NextGen low complaint numbers, these noise levels were “acceptable” in our area to most. NextGen eliminated this more equitable noise sharing and concentrated air traffic into tight corridors that slammed certain neighborhoods and devastated the relative “suburban” quiet these neighborhoods had enjoyed till then.

    We all enjoy the freedom and goods that the airports and airplanes provide, but the noisy downside must be shared more equitably and restored as much as possible to what it was like before NextGen.

    Fixing the noise impact issues is not about being against NextGen or opposed to modernizing the way planes fly and in no way decreases safety or affects “on-time” performance – it only addresses how the planes are proceduralized in the few miles before landing and during take-off. It’s all about restoring the noise burden conditions as much as possible to what they were before NextGen was implemented.
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    1. What is “noise shifting?”

    Noise shifting is taking noisy conditions and recreating those same noise levels someplace else. It takes a problem and gives it lock, stock and barrel to another community. It’s not the same as restoring aircraft traffic patterns. Restoring noise conditions as much as possible to the way they were prior to NextGen or finding better, quiet options is not “noise shifting.”
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    1. What does “restore” the noise patterns mean?

    The quality of life and development of neighborhoods are greatly influenced by the conditions and factors surrounding them. Noise is a big factor in many people’s decisions to live where they do. The FAA’s unilateral decision to end dispersion of airplane noise over the East Bay and concentrate Oakland and San Francisco Airport air traffic into narrow corridors over certain homes and neighborhoods had the significant impact of creating new sacrificial noise communities that did not exist before. “Restoring” means attempting to re-create the dispersed historical noise patterns that existed prior to NextGen as much as possible. It is all about righting a wrong, and is the equitable and just approach.
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    1. What does the FAA mean by “no significant (noise) impact?”

    Measuring noise is complicated. The FAA does not measure and monitor sound in most areas, but uses computer modeling based on what most experts outside the FAA judge as an inadequate cumulative and diluting method called a “Day-Night 24 Hour Average Sound Level” or DNL for short. The FAA also adopted an average of 65 decibels all day and all night (“DNL65”) as the noise threshold for when noise gets loud enough to require mitigation action. The World Health Organization disagrees and sets the threshold for noise toxicity at DNL55 decibels.

    The FAA does not consider the additional noise from concentrated aircraft patterns to become “a significant impact” or actionable until it surpasses DNL65 by at least 1.5 dB’s or if the increased noise resulted in an area having a new noise level of DNL65 that did not exist before. For all practical purposes, this threshold is impossible to reach outside of being adjacent to a runway. So, all affected communities under the new, highly concentrated flight corridors are simply told the dramatic noise increase is “not a significant impact” on their lives, property and quality of life.
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    1. What is a quieter, near idle descent?

    A quieter, near idle descent is called an “Optimized Profile Descent” or “OPD” in FAA speak. It’s a great navigation tool and procedure that is possible using GPS and the Performance Based Navigation methods that NextGen offers. An airplane utilizing an OPD uses a computer to calculate the plane’s ability to descend into an arrival pattern using the most economical power setting at or near at idle. This is the quietest way to fly an airplane. It is the preferred way to descend as it minimizes, or even eliminates, the need to “level-off” and fly level to slow the airplane down using noisy engine power. OPDs not only reduce noise, they also reduce fuel consumption, and emissions.
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    1. What is being done to address the airplane noise issues in the East Bay?

    At the request of the FAA, and in response to the dramatic increase in aircraft noise complaints from East Bay residents, the Oakland Airport-Community Noise Management Forum accepted the task of working with its members and community groups to provide the FAA with recommendations and proposals to adjust and revise NextGen routes and procedures in order to address noise concerns. The FAA has agreed to review such proposals and explore modifications to mitigate aircraft noise impacts that arose from NextGen in Alameda and Contra Costa Counties.

    A set of community-driven noise proposals was prepared by the Oakland Airport Noise Forum with input from multiple community advocacy groups, including Save Our Skies East Bay. The proposals were sent to the FAA at the end of March 2017 for consideration.
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    1. What about a lawsuit?

    The FAA has agreed to engage with the East Bay and consider noise mitigation proposals. As a result, a set of community-driven noise proposals was prepared by the Oakland Airport-Community Noise Forum with the input of multiple community advocacy groups, including Save Our Skies East Bay. It was sent to the FAA at the end of March 2017. A lawsuit at this time would be costly and counter-productive, as the proposals and mitigation would be sidelined. Hopefully, working cooperatively with the FAA and the Noise Forum will produce positive changes. If not, then there are other avenues can be explored.
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    1. Why can’t all of the planes just fly over the Bay?

    Planes are arriving and departing to and from all four directions from three very large international airports in the Bay Area – Oakland, San Jose and San Francisco Airports. There simply isn’t enough Bay to accommodate all of this traffic.

    Further complicating the already tight air space is the issue of weather. Many may notice that during stormy weather, planes don’t fly in the normal patterns. This is because planes must land and take-off “into” the wind. In stormy weather, the winds in the Bay Area can flow in a reverse direction than they normally do, forcing planes to land and take-off in the reverse way too. Wind patterns don’t seem to follow any rules, and there can be a reverse flow at one airport and not at another. Because of this, air traffic gets snarled and becomes very complicated, very quickly, which makes using the Bay for all traffic even more challenging.

    Noise relief from using the Bay is possible during night time hours when air traffic levels are much lower. In essence, the amount of room over the Bay can accommodate low traffic levels. Special late night noise abatement departure routes exist for Oakland and San Francisco Airports, and these do provide relief to East Bay residents.  Unfortunately, there still are very loud, low flying aircraft during night time hours, but these are arriving aircraft, which currently don’t have special night time routes. Night-time arrival routes will become a consideration if a more permanent solution for Oakland arriving flights cannot be accommodated.
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    1. What is the timeline to effect changes?


    On March 27, 2017, the Oakland Airport-Community Noise Management Forum sent a package of NextGen noise mitigation proposals titled Supplemental Proposals to Revising the Northern California Metroplex For Alameda County/Contra Costa County to the FAA for consideration. The proposals document specifically requests that the FAA provide a timeline for the process, however, we don’t know when the FAA will respond with their opinions and ideas regarding the proposals.
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    1. How does the FAA measure and evaluate airplane noise flying overhead; and do their analyses accurately measure the experience of people below the flight paths?

    Sound and measuring noise is complicated. The FAA does not measure and monitor sound in most areas, but uses computer modeling based on what most experts outside the FAA judge as an inadequate method called a “Day-Night 24 Hour Average Sound Level” or DNL for short. The FAA also adopted a threshold of noise being an average of 65 decibels all day and all night (“DNL65”) as being the litmus test for loud enough to have to do something about. The World Health Organization disagrees with the DNL65 and sets their recommended noise toxicity threshold at DNL55 decibels.

    Although DNL is a mathematical average, how sound is measured in decibels (dB’s) is not. The average suburban home has ambient noise levels of 40-50 dB. Based on many studies of how our ears “hear,” scientists have determined that for every increase of 10 dB’s, the loudness one experiences is doubled. For comparison on how loud 65dB is, a vacuum cleaner or standing 50 feet from a freeway is about 70 dB. Exceeding the DNL65 standard is practically impossible in a quiet, suburban area. It would take 100 planes flying overhead at 94.4 dB each to create a DNL65 (http://jdasolutions.aero/blog/nextgen-noise-study/). To get a sense of this, a train whistle clocks in at about 96 dB. If a train went through your living room blowing its whistle a little under 100 times a day, it would reach a DNL65. That’s really loud and not a reasonable metric to use as a threshold for “noisy.”

    From NextGen Noise: RNP’s Concentrated IMPACT May Justify Substantive Change In FAA Policies Under A Proper Study by Cynthia Schultz December 28, 2015, in JDA Journal, accessed April 2, 2017 http://jdasolutions.aero/blog/nextgen-noise-study/

    In addition, the FAA noise model does not take into account the adverse effects of intensely loud, single-event noises, even though this was mandated by the Congress and California law requires it. Thus, a single plane that registers at 80dB flying over a quiet neighborhood is not acknowledged as an adverse impact itself, but merely averaged and diluted into the noise over a 24-hour period. Fifteen years ago, California legally recognized the environmental significance of such single-event impacts as stated in Berkeley Keep Jets Over the Bay Committee v. Board of Port Commissioners, 91 Cal.App.4th 1344 (2001). The FAA can legally contradict the State, because NextGen is a Federal program and not required to abide by California environmental impact rules. It doesn’t make sense, but that’s the way the law works.

    The FAA does not consider the additional noise of concentrated aircraft noise to become “significant” or actionable until it surpasses a DNL65 by at least 1.5 dB’s or if the increased noise resulted in an area having a DNL65 that did not before. This threshold is, for all practical purposes, impossible to reach outside of being adjacent to a runway. So, all affected communities under the new, highly concentrated flight corridors are simply told the dramatic noise increase is “not a significant impact” on their lives, property and quality of life.
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    1. What is night time noise abatement, and why do I keep hearing really loud planes late at night?

    Night time noise abatement routes are designed to:
    • Move departing aircraft from Oakland and San Francisco Airports over the San Francisco Bay as soon as practicable
    • Keep the departing aircraft over the water during the lower and noisiest portion of the aircraft climb until they get to higher altitudes where they are less disturbing. They can then turn over land towards their destination.

    These routes provide a significant benefit during night-time hours when ambient noise levels are at their lowest, as a thundering airplane makes a bigger impact on sleeping communities than they do during daytime hours. Night hours are currently considered to be between 10pm-7am, Monday to Saturday. An extra hour is thrown in on Sunday, a “day of rest,” allowing us to sleep-in until 8am. Even though this route works at night, it isn’t feasible during the day for all air traffic. Unfortunately, there are so many planes during the daytime, there is simply not enough room over the Bay for planes to use these routes all of the time.

    Before the Air Traffic Controllers (ATC) enforced these night-time routes, communities experienced significant sleep disruptions because planes routinely turned over Oakland and Berkeley soon after departing instead of flying up the Bay as they are charted to do. These early turns resulted in aircraft flying at much lower (and louder!) altitudes over the East Bay. In February 2017, ATC became serious about enforcing Night Time Noise Abatement routes helping East Bay communities get their zzzz’s.

    So, why do you still hear loud planes late at night? The night-time noise abatement routes are only for departing Oakland and San Francisco traffic. Inexplicably, there are no quiet night-time routes designed for arriving airplanes. This means all the late-night FedEx, UPS and commercial aircraft arriving from northerly areas fly the same noisy WNDSR route that they fly during the daytime. WNDSR forces arriving planes to fly flat along the East Bay Hills under power at low altitudes instead of using the quieter, gliding arrival procedures touted by NextGen. Because of the way it was designed by the FAA, this route can never be quiet. Unfortunately, WNDSR forces planes to fly in the noisiest, most polluting, and least fuel efficient way day and night. Because it’s so quiet at night, the adverse noise effects are even more noticeable.

    The NextGen noise mitigation proposals (make this a link to our proposal page), submitted to the FAA in March 2017, include recommendations to mitigate the East Bay’s current late night noisy arrivals problems.
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