Possible answer to Planefag ask / Notible on #8312 by >>6500087 (previous bread) with responses from >>6500537 >>6500563 >>6500578

That pattern is around the perimeter of Moffett Federal Field, Mountain View, CA

Besides NASA Ames Research Center, the birds you are looking at are from the California Air National Guard (CANG) 129th Rescue Squadron. They have some high end HC-130J airframes that do more than just aerial refueling

https://www.129rqw.ang.af.mil/

Additionally, there are some Soopy EW ‘sniffer’ turboprops (??? US entity ownership??) that hang out that are not associated with the 129th. Those are made to 'look/appear' like US Army transportation command…..??? but that activity does not exist at that airfield.

Of note: the western end of that pattern is directly over Google’s HQ and campus in Mountain View. North of the 101