Your last strikes are probably coming in right about now. With any luck this airport is a smoking ruin and will take several days of concerted effort to repair.
If you weren't quick enough at closing the base, some of the resident aircraft may have taken off, well, you have guns for that. If you were quick, you may have kept all aircraft on the ground, you can see them in the parking areas but not the ones in the hanger. Make sure you kill that just in case. You can always re-task assets to focus on these guys once you find them. An airbase with no aircraft is not much good to anyone, and the best enemy aircraft is a smoking pile of twisted metal, no matter how it arrives at that state!