Deb wrote:
From here Thunderhawk (no.2) can then fly off performing a ground attack against a target, possibly the enemy I just finished defeating, hitting them with BM and possibly destroying through BM and killing units off from failed saves, or a new target that I fly over.
It sounds like the others have mostly sorted your question out but I think you're misunderstanding this bit. If Thunderhawk 2 deploys by planetfall then it can activate later that turn, but only as an immobile ground unit, so it could with sustained fire say. It can't do a ground attack the same turn it planetfalls. In the end phase it can either remain as a ground unit on into next turn or fly off and disengage.