Sonoma County Airport Referral Area
Although Sonoma County Airport is situated in predominantly agricultural countryside northwest of Santa Rosa, the nature of the airport’s activity is such that its area of influence extends many miles from the airport property. The instrument landing approach to Runway 32 results in an approach zone which extends nearly 10 miles southeast of the runway. Additionally, the high volume of airport operations compared to the other five airports, plus the substantial number of business jet and large, piston-engine aircraft operations, results in a 55 CNEL contour extending 1.0 to 2.0 miles beyond the runway ends.
The primary referral area is shown in Exhibit 8D. Its greatest extension is to the southeast where it reaches Guerneville Road and then cuts back north to Piner Road in the southwest. On the southwest and west it follows a series of parcel lines. On the north, the line follows parcel lines, airport safety zone boundaries and the Town of Windsor’s sphere of influence boundary. To the northeast and east, U.S. Highway 101, Fulton Road, and a series of parcel lines averaging 2,500 feet west of Fulton Road define the boundaries.
The outer boundary of the referral area and AIA area includes the conical surface under FAR Part 77 and areas within the 55 CNEL noise contour. It also takes in areas to the northwest and southeast commonly overflown by low-flying aircraft (1,000 feet or less) using the instrument approach to Runway 32 or following the ‘non-precision instrument approach path for Runaway 14.