You will require a way to track your ground targets (tanks), as well as your ammo/ordnance (bombs) that you drop onto it.
I am not familiar with the tank demo you're referring to, but it seems this is using statically placed 3D models?
If that's the case, it seems simple: you could just look up their gps coordinates and write them down, so that you know where the 3D models are placed.
Once you've got that, next thing is to actually track your ordnance.
So, what plane are you referring to?
Assuming that it is using
submodels, it should be possible to determine the point of impact (terrain contact), i.e. getting gps coordinates for each collision.
These can then be written to and processed by the property tree, using for example a
Nasal script.
Next thing to do would be to define the effect for your ordnance: assuming you want each impact to "destroy" everything within a radius of say 3000 ft, you now need to check if your statically placed 3D models (the tanks) are located within any of these circular sectors (i.e. determine if a gps datum lies within an area of another gps datum with a fixed radius).
If a 3D model actually does lie in any of the "destruction sectors", you'll want to trigger a destruction animation for it (e.g. by just using the wildfire animation) in order to illustrate successful hits.
Similarly, you'll want to proceed for gunshots: determine their points of impact and track these using a script.