Central California Ozone Study (CCOS) - Desert Research Institute

CCOS Field Operations Plan Version 2: 5/31/00
Figure 2.6-4 gives a schematic presentation of the form of the flight pattern without
geographic reference. The northern-most way point is at Sonoma while the southern-most is the
Angiola tower. The top portion is flown in a clockwise direction while the bottom portion is
flown in a counterclockwise direction.
Gird cells 50x50 nautical miles
Grid cells are 50x50 nautical miles
1st circuit
2nd circuit
Figure 2.6-4. Fresno area flight patterns for morning flights with low-level passes or spirals at key way points
(left) and afternoon flights with circuits above and within mixed layer (right).
Western In-Flow Boundary
Morning flights depart from FAT between 6 and 7 a.m. PDT. Way points for these
flights are listed in Table 2.7-13 and are shown schematicaly in Figure 2.6-5. From FAT to the
coast, the flights are at the recommended minimum altitude for clearing the terrain along the
Pacheco Pass route toward Monterey Bay. Once over the coast, the flight descends to minimum
allowable and safe altitude, which could be restricted to 2000 MSL because of the coastal marine
and wildlife sanctuaries, but which, if permissions are granted, could be as low as 300 ft MSL.
Minimum altitude could be further restricted by offshore fog and stratus cloud decks.
Turn point #3 begins the first of three long transects that are roughly parallel to and 10-20
nm, 40-50 nm, and 90-100 nm from the coast. The 1 st transect intersects Class B airspace west
of San Francisco and ATC may request routing around or below the controlled airspace. The 2 nd
and 3 rd transects require entrance into several military warning areas. A continuing series of
Chapter 2: FIELD MEASUREMENTS 2-66