I was based at DaNang AFB in 68-69-70. During that time it was the busiest airport in the world. Two runways, each two miles long, with an average of one take-off or landing every 30 seconds, 24 hours per day. Trying to work in a civilian timetable would just not cut it if a military airfield needed to go to a war footing.
And we may one day have "problems" with a certain country located not too far from S.D. ....