Aviation units are typically part of a Regiment that is organic to a Division. So when the Division plans an engagement or battle, they have their own aviation units that they can assign whatever OpOrder they deem necessary. This is, of course, a generalization. There are aviation units outside of the aviation regiment but still in the Division. Most of your Air Ambulance units fall into this category. My first Army Reserve aviation unit was in the standard aviation regiment T.O. for an Army Reserve Division. We were a "lift" Company and flew UH-1H's (slicks) doing ass & trash type stuff. My last AR unit was an Air Ambulance unit and we belonged to a Medical Brigade. Still in the same Division as the rest of the aviation units, but since they have a completely different role, they let the docs decide what to do and where to go.
Where I am going with all this is that yes, there are lots of support roles for Army Aviation units (the lift companies and Air Ambulance), but a -58 and a -64 flying together looking for bad guys is NOT a support.