AI transport helos

[Imp]

Long time since I did it but certainly attack helicopters follow waypoints at least to a degree. You can place multiple waypoints to slow them down & make them stop behind a ridgeline or some such.
The AI is then normally quite good at attacking from that point.
As Airborne Rifles mentioned I would expect transports if slow moving to unload once they are within the general area of several victory hexes. Probably around 12 -15 hexes out based on land transport vehicles.
So hopefully out of range of any defending infantry.