Thats a pretty arbitrary distinction. Until we get area-specific explosions (ie, different explosions for powerplants cooking off, magazines exploding, fuel tanks rupuring etc) we're going to have to live with compromise.
T and V technology is largely interchangable by FS2, so why would their explosions be different colours? Where does the 'stuff' of the explosion come from anyway? Is it fuel, or armour, or cocaine, or what?