[Pursuivant]

Current Train AI has it ignoring any object placed on a railroad track and passing right through obstacles which should derail or destroy it.

Obviously, this isn't an issue for a well-designed mission, since who's going to put obstacles on a railroad? But, it could be an issue if an aircraft lands on a railroad track or if the mission builder deliberately places an object on the tracks to make a train destroy itself.

There could be very simple AI that makes trains slow and stop if there is any object on the rails ahead of them out to some distance (perhaps 2 km during the day under clear conditions, less for rain/snow and/or night).

Trains and ground vehicles also ignore bomb craters from bombs which hit roads or railroads. Realistically, a big enough crater should stop or derail a train, or make a vehicle crash if it can't avoid it. The simplest solution to deal with this problem would be to make bombs spawn bomb crater objects when they explode on a railroad track or road section. Bombs that land elsewhere would still spawn the current bomb crater texture.

Currently, the bomb crater object makes ground vehicles do the "bump, back up and turn" collision avoidance routine. Adding simple AI for trains, as described above, would make the bomb crater object into an effective roadblock for railroads as well.

or if bomb behavior was altered so that bombs on roads and railroads spawn bomb crater objects.