A very interesting read...
Following his "missing" in 2007, I spent many hours with my Maps of the Sierra Nevada mountains, and my FS2004 Simulator, "Flying " around the area trying to replicate any problems he may have had on his journey from Nevada in the direction of the California Central Valley.
The Sierra Nevada Mountain Range is notoriously dangerous for Pilots of Light Aircraft.
In FS 2004, my small Piston Prop Aircraft fitted with Carburettors, regularly suffer from "Icing", including the Pitot Tube, when traversing the 10,000+ feet Snowy peaks!
There is nowhere to land safely when trouble strikes!
Paul...G-BPLF...FS 2004... 8-)...!
...Maps out...going to have another peek at Highway 395 again...

...!