San Marcos, CA Noise Ordinances: Aircraft Noise (2026)

04 governs noise at the City's airports. 370 is the baseline rule: every person operating aircraft from a City airport must comply with all noise abatement procedures, traffic patterns, and policies the City establishes, provided those measures are acceptable to the FAA. 380 adds a numeric ceiling specifically for training flights: only aircraft whose takeoff or landing noise does not exceed an effective perceived noise level of 90 decibels, measured or estimated at a sideline location 450 meters, or 1,500 feet, from the extended centerline of the runway, may conduct training flights at City airports.

The section defines "training flight" broadly to include any instrument or approach to the airport flown for student instruction, pilot proficiency training, or pilot evaluation check rides, whether or not the aircraft actually touches down. The noise measurement method is not left to City discretion: it must follow FAA Advisory Circulars 36-1B (December 5, 1977) and 36-2A (February 6, 1978), including any later revisions, which the ordinance incorporates by reference. 390 applies the identical 90-decibel, 1,500-foot standard to any aircraft seeking to establish a permanent base of operations at a City airport, and defines a "permanent base of operations" as existing whenever an airport serves as an aircraft's base for flight operations, maintenance, or storage for more than 21 days in a calendar year.

Together, the two sections mean a loud aircraft can still land at a San Marcos airport occasionally, but it cannot be based there long-term or used repeatedly for training touch-and-goes unless it clears the 90-decibel sideline threshold. 460.