Fact Check:  "It has been projected the number of low altitude aircraft flights will increase to approximately 50 cargo aircraft overflights a day..."
Asserted by many sources; this specific quote is from Resolution No. 2007-28 of the El Dorado Hills Community Services District.

Update:  Extreme claims of future freighter traffic

A public comment at the August, 2009 meeting of the El Dorado/Folsom Joint Powers Authority said that under current planning there would be 600 freighter overflights per night over El Dorado Hills and Folsom.  There is no analytical or documentary basis for claims of freighter traffic at this level.  Consider these comparisons, where Fed Ex is the main cargo carrier at Memphis, the world's busiest airport for cargo, and San Francisco International has a similar volume for all flights, passenger plus freight.:

overflight projections

* CEQA (the California Environmental Quality Act) requires environmental impact reports to assess the maximum theoretically possible level of impacts. For Mather the maximum air traffic flow for cargo is limited mainly by ramp space and ground facilities. The extreme claim of 600 arrivals per night would correspond to about 120 operations per hour, one takeoff or landing every 30 seconds throughout the night. This also is impossible, especially for approaches, because of air traffic control regulations for separation between aircraft.

The claim of 50 overflights per day is incorrect.
The actual forecast produces a range of 9 to 13 overflights per day.
Minimum altitude is typically about 2,800 feet above ground level over the highest point on EDH's west ridge, higher at all other locations in El Dorado Hills.

Overflight count  The base range forecast (considered most likely) results in an average of 9 daily overflights.
  The high range forecast results in an average of 13 daily overflights.
  No forecast results in 50 daily overflights.

Demand to use Mather for air carrier cargo operations depends on the region's economy. For air carrier cargo operations the Mather Airport Master Plan projects a base range rate of 10,600 operations per year in 2021 and a high range forecast of 15,300 operations per year.

Half of the operations are takeoffs, half are landings. Normally no departures overfly El Dorado Hills or Folsom. Flight track records for 2008 show that only 64% of approachesoverfly EDH and Folsom.

Operations are are takeoffs and landings. No air carrier cargo departures overfly El Dorado Hills: Only arrivals may produce overflights, the number of arrivals is half of the number of operatioins. Of all arrivals, current flight track records show that 64% overfly El Dorado Hills. Therefore, the number of overflights of EDH are forecast to be:

Operations per yearTotal approaches per year:
Half of operations per year		Overflights per year
over EDH and Folsom
64% of total approaches		Average overflights per day
over EDH and Folsom
Overflights per year divided by 365
Base Range:10,6005,3003,3929.3
High Range:15,3007,6504,89613.4




References 
Return to   Mather 2008 Update     SierraFoot home page