Am completing all of Arizona now.
So I'm over the same maps a few times, my observations on Air Drops.
A: Air Drop indicating on Metal Dector but NOT Found.
B: Not found Air Drops appear on map after reloading.
C: Air Drops are sometimes 'discovered' a few times.
Air Drops in different locations on the map.
F: |Ocassionally one has to physically drive on an Air Drop to find it.