Analysis of FAA Proposal of May 19, 2016

The FAA delivered three PDF documents about changes to the Metroplex. You can download them here:

  1. FAA NorCal Metroplex Executive Summary Feasibility Study

  2. FAA NorCal Metroplex Initiative Phase One Report

  3. FAA NorCal Metroplex Initiative Phase One Appendices


On Friday afternoon, Quiet Skies Mid-Peninsula sent a summary analysis to its mailing lists. Read the letter here. It makes many of the same points that we make in our longer analysis, below. It also announces a public meeting to be held at the Los Altos Hills Council Chambers on Saturday, June 4, between 10am and 12:30pm.


Instead of taking a thoughtful look at the noise complaints of thousands of Bay Area residents and attempting to devise solutions, the FAA asked non-experts to make recommendations for technical procedure changes. Then, the FAA rejected a number of those recommendations out of hand because they were “not feasible” under existing FAA technical criteria. This was an entirely predictable (though disappointing) outcome: the FAA should not be asking lay people (who are not aviation experts) to recommend technical changes which must meet the FAA's own technical requirements (e.g. "overall fly-ability").

Before getting too excited about the FAA's response and the Quiet Skies NorCal ("NorCal") claims that the FAA's response is good for Los Altos and Los Altos Hills, consider the following:

    • The FAA has not stated a noise reduction target for any of these changes.

    • They are not measuring the aircraft noise on the ground in our community.

    • They have made no commitment to reduce that noise on an ongoing basis.

    • They have not offered any long-term solutions to the Bay Area's airplane noise problems (despite committing to this in July 2015).

    • And they have not acknowledged the health and learning impacts associated with the airplane noise over our homes and schools.

What is their target for noise reduction? Who will hold them accountable if we do not get sufficient noise reduction? Who will ensure that any noise reduction is achieved and maintained over time?

Unfortunately: *not* the Select Committee appointed by Reps. Eshoo, Farr, and Speier. Santa Clara County Supervisor Joe Simitian (chairman of the Select Committee) said on Saturday, May 14, in a Los Altos Community Forum that the FAA, the Congressional Reps, and the Select Committee are not intending to stay involved with this problem for more than a few months.

We need our elected officials to insist that the FAA stay engaged, commit to continuous improvement of noise, and measure (with appropriate metrics) the actual noise on the ground before and after any changes. We also need our elected officials to hold the FAA accountable for results. The combination of politicians who want to move on to other issues, and a very narrow 'menu' of options to be entertained by the FAA should have you all very worried.

Addressing Los Altos and Los Altos Hills specifically, our assessment is, unfortunately, different from the Quiet Skies NorCal group's position. The leadership of that "NorCal" group lives in the Santa Cruz Mountains (Los Gatos, Saratoga, Soquel) which probably will see the maximum benefit of what the FAA has deemed feasible. We believe they dramatically overstate the benefits for Los Altos and Los Altos Hills.

The primary benefit to LA/LAH described in the FAA response is the possibility of allowing more planes to make an "engine idle descent" on the SERFR path (gliding more quietly along the route, instead of alternately applying thrust and brakes). Ironically, the original intention of SERFR was to permit "engine idle descent", but this goal was not achieved when NextGen was delivered in 2015 because the "Class B airspace" was not correctly configured. The revisions now proposed by the FAA are a nice demonstration of why "continuous improvement" is the only winning strategy.


Consider the following shortcomings in the FAA document:

    1. The FAA says our airspace is already too crowded to keep all planes on "idle engine descent": >50% of flights that start off on SERFR are currently "vectored" (verbally redirected) by air traffic controllers and thus unable to have an "engine idle descent". Once vectored, the planes have to apply thrust and speed brakes to comply with ATC instructions—this is very noisy.

    2. Don Gardner's analysis of the concentration of aircraft flying the old BIG SUR flight path (pre-NextGen) and the current SERFR flight path shows that there are now 45% more planes over Los Altos than before NextGen, they're spread over a much more narrow ground track, and they're lower in altitude. The FAA's proposed tweaks to SERFR don't address any of that, so don't count on getting back to a pre-NextGen noise level. That's not going to happen.

    3. The loud "Airbus whine" from A320-family planes is not reduced: that noise is the result of air rushing over fuel vents--a design flaw which can be corrected with the installation of simple parts at a cost of $3k per plane. Newly-built A320s are built with these parts installed, but the existing domestic fleet of aircraft has to be retrofitted (something airlines have committed to do in Europe).

    4. SERFR (from the South) isn't the only source of noisy airplane traffic over LA/LAH. More planes enter the Mid-Pen airspace as vectored traffic from OCEANIC arrivals from the West and BDEGA arrivals from the North. There's nothing in the FAA's response which will reduce noise from these other arrival routes.

    5. LA/LAH also receive some SFO and OAK departure traffic. Though some tweaks to departures are identified by the FAA as ‘feasible’, those commitments focus on the first leg of departures (over San Mateo County) and overflights of the Santa Cruz Mountains—not the flights over LA/LAH. In fact, the FAA says “departures to the south have historically been vectored as soon as possible. It is unlikely any procedural adjustment would significantly change the way southern departures are actually flown”.

    6. The FAA has made no commitment to reduce or eliminate residential overflights from nighttime arrivals (those planes waking you up at 2am).

There may be some initial benefit from some superficial tweaks to SERFR but, because of the above-stated reasons, we believe any noise reduction will be relatively modest and will be short-lived.

Furthermore, without any commitment by the FAA to distribute the planes more fairly, LA/LAH (and the Mid-Peninsula region more generally, including East Palo Alto, Woodside, Portola Valley, and Palo Alto) will continue to bear an unfair share of noisy airplane traffic—and the brunt of future increases in numbers of flights to SFO.


We at QSLAH have consciously not joined the rush to propose specific solutions. We believe that potential the remedies that will make up effective solutions are well understood. These include:

    1. Moving more arrivals over water. Potential examples abound. One is to move more Northern arrivals from the peninsula (West Leg) to the San Francisco Bay (East Leg). Another is to move more SFO southern arrivals east, over the Bay.

    2. Dispersing flights. Turn back the FAA's decision to concentrate flights over narrow "sacrificial noise corridors" and disperse them so that a single line of unlucky neighborhoods does not bear the brunt of SFO arrivals.

    3. Adopting "idle engine" arrivals. The focus should be not simply on Southern arrivals (e.g. SERFR). These "idle engine" arrivals should be the norm for flights from all azimuths.

    4. Limiting night arrivals, especially of noisy 4-engine cargo aircraft. These flights may comprise a relatively small number of flights, but they account for a large fraction of aircraft noise disruption.

    5. Minimizing vectoring. Vectoring is a special problem over the mid-peninsula. Vectoring generates a large fraction of the noise we hear because it both requires engine thrust (noise) and increases the time that aircraft are over our heads. Vectoring is not a kind of dispersion.

    6. Retrofitting Airbus aircraft. Install the "vortex generators" over the fuel vents on the wings of all Airbus models that were not fitted with these devices when the aircraft were originally manufactured.

    7. Restricting aircraft numbers. Noise pollution is not free. Airlines cannot use the Mid-Peninsula as a no-limits dumping ground for noise. Raise the costs of landing slots to push airlines to use fewer, larger aircraft. We don't need a flight from SoCal every 20 minutes. Every 30 minutes is enough.

We believe that it is the responsibility of the FAA to assemble these possible remedies into viable solutions for every metroplex. If you're unhappy about the noise being dumped by the airlines with support from the FAA, contact your elected representatives and join our efforts.