There’s also a long-range missile launcher to take out trains without a fight. You have to purchase and store missiles in cargo wagons and manually enter the launch coordinates, then hope for the best. It’s extremely hard to hit something imo. A better use of missiles is to combine them with scout cars to make a bomb car. They will stop any train they hit for a while. Regular scout cars are great to see if the tracks ahead are safe.
You can also use spies to blow up the train tracks. It will take a while for the Viking Union to repair so you can get away. Spies are free but you do need a special wagon.
And you can buy an observation wagon, the big one in Peking I think. Improves your vision range, more or less a must have. Otherwise you won’t see approaching trains in time.