Passing loops
Several trains on one line, and double track.
A passing loop lets two trains share a single line: they meet at the loop and pass.
- Build the main line between your two stations.
- Partway along, lay a second track that leaves the main line and joins it again.
- Make the loop at least as long as your trains: a locomotive is a little over half a tile and each wagon half a tile.
That is all: a loop needs no signals.
How trains pass
A train drives onto a junction only when the junction is clear, and so is the track it leaves it by, up to the next junction or signal. A train that finds the single line ahead taken waits on its side of the loop, and the train coming the other way takes the side that is free.
One-way signals still work on a loop: they keep the trains going each way to their own side. See Signals.
Double track
For a busy line, lay two tracks side by side and make every signal one-way, pointing the way trains run. A signal every few tiles lets trains follow each other closely.
Deadlocks
A train that has waited about a month at a signal or a junction gives up: it turns round and heads for another of its stops, if the track behind it leads to one. If not, it goes on anyway, and crashes if the train it waited for is still in the way. Take a long wait as a sign that the line needs another loop, or a longer one.