Three trucks, probably an International in front

It's a late 50's or early 60's International Harvester. The Navy has a history of air fields in inland areas for use by Navy pilots who were training for coastal combat and bombing (Navy planes are/were used in the Middle East wars). Klamath airport was once labeled Naval Air Station Klamath Falls but that designation ended in the 40's. There is, though, continued association of the airport with Oregon Air National Guard and thus equipment that was associated with the airport might be labeled as Navy. I looked to see if the truck might have come from northern California, but that doesn't seem to be the case.
en.wikipedia.org/wiki/Klamath_Falls_Airport