To and from RIV

Can anyone tell me about flights to and from RIV? A number of airlines serve this airport, the flight show on Flightaware, but you can’t go online to purchase a ticket. I am guessing that the air force base fills the planes and has an internal way to book tickets.

You are able to observe the main geo and tech data from one of the U.S. agency’s source.
You did not underline, whether you were in need to buy a trip for the charter jet or a passenger ticket for the scheduled air carrier.
The chances to land is upon the level of an emergency on-board situation for non mil jet at this air field only.

Those are government contract flights (charter flights).

Government civilian employees can request to use one of those flights, but they are low priority, behind military. You can wait for a week or more to get a seat.
Biggest provider now days is Atlas Air.