I'm thinking California East of the Sierras. Mono County, Inyo County, San Bernardino County, slivers of Riverside County, and Imperial County.
If you're in Amargosa, Shoshone, Tecopa, Wonder Valley, Lanfair Valley, Kelso, Amboy, Cadiz, Fenner, etc., it's a long way off from anything.
Pop open Gooogle maps and try to find the nearest dispatch location for an ambulance to Fenner, and then put that into perspective with the amount of traffic on the I-40 corridor. CHP can call an airship, but I've seen burn patients sit dying for an hour while waiting for a helicopter to become available for dispatch.