Only military flights in Hilo the last few days?

[Midnight Rambler]

As rainyjim said the Air National Guard often does trainings with cargo planes - they touch down, take off again, then circle around Hilo Bay and do it again. Sometimes for a couple of hours at a time. It can be kind of annoying but if there's ever a disaster where they need to fly supplies in, you'll probably be glad they're familiar with it.