https://www.metabunk.org/debunked-only-four-airliner-flights-day-over-mt-shasta-ca.t622/So, just a (feeble) attempt at getting to topic? Shasta is still a "thing"??? Seems.....it was a "Town-Hall" type of meeting....about a year ago?
I see Mick's post just up-thread (apologies as I get "up-to-speed").
Perhaps once again, a description of just how many Upper-level Jet Routes exist in that vicinity? To explain the preponderance of (sometimes) persistent contrails, when upper-level conditions are conducive for their formation?