Spring RTS Engine

As the title says; as gunships have the obvious advantage of being airbourne, it would be nice if there was a widget that would make attacking gunships automatically fly around the back of a unit to gain flanking bonus from their attack. Doable?

Sounds like it could work with 1 target and a whole lot of motion control, but it also sounds like a major pain in the ass math wise, at least to make it look decent.