Signals 101

To successfully compete in the dog-eat-dog world of Transport Tycoon, your rail system needs to be tuned to perfection. An efficient and well-planned signalling system is a must. Transport Tycoon Deluxe provides an extensive amount of control over the behavior of your trains, although an exhaustive search through the game manual would never reveal this fact. Here in the pages of the Transport Tycoon Deluxe Strategy Guide, the lost art of signal system engineering is brought to the light of day.

I discovered early on that trains act differently when faced with one-way signals than they do with two way signals. Upon first observation, the effects can sometimes be baffling; it is only after close study that the pattern begins to emerge. To summarize:

• Anytime you want to give a train the choice of using any two or more lines which lead to the same destination, use TWO-way signals at the head of each line.
• Anytime you DON'T want trains to take another line if the one they WANT is red, use ONE-way signals. The train will wait for its desired line instead of using the wrong line.

At first the behavior seemed like a bug, but if you think about it, this gives you an enormous amount of control over how your trains act. For instance, in this screenshot, if some trains need to ALWAYS go from station A to B and some need to go from A to C, using one-way signals (D) at the intersection will prevent trains which are heading to B from going to C instead, and vice-versa.

Putting it all together:

Using this knowledge, we can design stations which handle trains with efficiency and speed. While designing a high-traffic station, there are three things which should be incorporated to ensure a smooth operation:

1. Overflow Track: If a train trying to enter a station meets with red signals at all four entrances, the fifth signal should be at the entrance of a track which loops back around and allows the train to take another run at the station. I call this an overflow track or a return loop, and it should be long enough to hold two or more trains, depending on the traffic you expect to service.
2. Mandatory Servicing: All trains entering the station should be mandated to enter a depot before getting in line to enter the station. This will prevent most breakdowns in the super-critical entrance to the station. This depot should be place in such a way that trains which have used the Overflow track will be routed back around where they will be serviced again.
3. Independent Exit Tracks: At the exit from a busy station, make sure you have EACH track of the station go through a signal, then 5 squares (or long enough to hold your longest train), then ANOTHER signal before they merge together into one track. This will eliminate delays caused when trains cannot leave the station because other trains are also leaving the station.

Remember to never use one-way signals at the entrance to a multi-track station if you want your trains to take any available track. With one-way signals at the entrance, every train will try to enter the first track of the station, and will wait for it when it is occupied, ignoring the other tracks which are available.

There are other examples of how to make effective use of signals, but they all depend upon the two axioms listed above. Virtually any signalling system you may need to build should be feasible once you understand these concepts.