A disputed change cannot be its own baseline

The FAA says it holds no analysis comparing the 2024 departure pattern with the route it replaced — yet that pattern is now the starting point every alternative is made to argue from.

By Malcolm Crawford

Discussion of aircraft noise in Sonoma County often begins from present conditions. The distribution of departures as it now stands is taken as the state of affairs, and the question at issue becomes how that distribution should be adjusted. An opinion column published in the Press Democrat on August 25 is a clear instance, and a useful one, because it sets out the reasoning explicitly rather than leaving it implied.

The column concludes that the noise should be dispersed across a wide landscape, and that the consideration of impacts should be dispersed too. That conclusion may or may not survive a comparative analysis of the affected communities. It cannot be established by treating the distribution introduced in 2024 as the neutral starting point.

Treating present conditions as the baseline decides the vocabulary

The RREHD ONE departure procedure — the satellite-guided route most departing airliners have followed since it took effect in January 2024 — produced the pattern now overhead. Take that pattern as the starting position, and every proposal becomes a departure from it. A reduction in west county departures becomes a transfer imposed on somebody else. A route introduced in 2024 acquires the standing of the settled arrangement, while the distribution that preceded it becomes a new proposal required to justify itself.

The conclusion is built into the frame. Once the present distribution is accepted as the baseline, the language of transfer and imposition follows automatically, and it applies to any argument conducted inside it. A remedy advocated by west county residents — returning departures to the corridor they used before 2024 — is reclassified as an imposition on others before it can be considered on its merits.

That reclassification does not depend on anything about west county. Any imposed burden becomes legitimate simply by being used as the baseline.

Two separate changes are being charged to one account

Restoring an earlier route would not restore earlier noise levels, because the airport now handles far more commercial traffic. FAA counts show that air carrier operations at Charles M. Schulz–Sonoma County Airport — each arrival or departure counted separately — have more than doubled over the past decade. The fact that flights pass over a particular community follows from routing. The fact that there are more of them follows from growth. Reverting to an earlier route would bring both changes to that corridor, but they would not have the same cause.

Describing the entire resulting burden as noise dumped by west county merges those causes. It makes residents contesting a route appear responsible for growth their request did not produce.

The starting point was never chosen

Both questions — where departures go, and how many there are — are real. Neither is answered by treating the present distribution as the baseline.

The FAA's response to the request is direct on the relevant comparison. It found no records of any FAA analysis comparing RREHD ONE with the previously published CHARLIE EIGHT departure procedure, because the agency did not create, maintain, or control such records.

The four-page environmental pre-screening form is consistent with that response. Submitted in March 2023 for the three new departure procedures, it provides fields at page 560 of the release for operations counts by aircraft type — helicopter, propeller, and jet — across daytime, evening, and night periods. Every one of the nine is entered as zero. Beneath them, against a field headed "Noise Sensitive Area(s)", the entry reads: None. The form contains no comparison of population exposure, ambient noise levels, existing community burden, or one corridor with another.

The released record therefore supplies no documented comparison showing that the present distribution was chosen over its predecessor on the basis of community impacts. What exists over west county today is the byproduct of a procedure geometry meeting a destination mix.

What is being used as the status quo is therefore not a settled allocation but an undocumented one. A distribution with no recorded comparison behind it has no special claim to be the point from which every alternative must argue. The question is not how far a proposal departs from 2024, but which distribution is justified, and on what grounds. No documented comparison of the alternatives has answered it. It remains open, and it is the question worth having.

Sources. IFP Environmental Pre-screening Filter, form KSTS_23323, submitted March 23, 2023, covering the CHRRO ONE, MMORK ONE, and RREHD ONE departure procedures: pages 558 to 561 of FAA FOIA release 2026-04927, the "Noise Sensitive Area(s)" entry at page 560. "Close to Home" column, Press Democrat, August 25, 2026. FAA airport operations counts for STS, 1990–2025, the full operations record.

Colophon: researched and drafted in collaboration with Claude (Anthropic).