How to have multiple trains share a platform

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From Version 1.9, the Advanced mode for stop creation allows trains to share platforms. In this mode, the player specifies the exact stopping point for trains, and provided that two trains will not overlap while stopped in the station, NIMBY will allow them to share the platform.

Platform sharing for trains arriving and departing in different directions[edit]

In the example below, the line A-B (red) runs from Ayton to Beesville, and the line B-C (green) runs from Beesville to Ceeside:

PlatformSharingABCLayout.png

At Beesville, both trains use Platform 1 simultaneously:

PlatformSharingBeesvilleTrains.png

The platform at Beesville is 250m long. Both trains are 80m long, and so there is plenty of space for both to use the platform.

On Line A-B, the stop at Beesville was created using Advanced mode. A stopping position 5m from the near end of the platform was selected, choosing the west-facing arrow marked as "245m":

PlatformSharingBeesville LineABConfig.png

Line B-C is set up in the same way, choosing a stopping position facing east at its end of the platform:

PlatformSharingBeesville LineBCConfig.png

Trains too long[edit]

If the trains will not fit in the platform simultaneously, the signalling system will not permit them to enter.

In the example below, both trains are 140m long, and they are too long for the 250m platform at Beesville. Train A-B arrived first and entered the platform, but train B-C is being held at a red signal because there is not enough room for it to fully enter the platform:

PlatformSharingBeesville TooLong.png

Complex platform sharing[edit]

The method above works for trains departing in different directions. For the Ayton-Beesville-Ceeside layout, the possibilities it can handle are:

  • Train 1 arrives from the Ayton, reverses at Beesville, and departs back towards Ayton. Train 2 arrives from Ceeside, reverses at Beesville, and departs back towards Ceeside. In short, there is an A-B-A train and a C-B-C train.
  • Train 1 arrives first from Ayton, stops at the far end of Beesville, and departs towards Ceeside. Train 2 follows Train 1 from Ayton, reverses at Beesville, and departs back towards Ayton. In short, there is an A-B-C train and an A-B-A train behind it.

The method above will not work for:

  • Train 1 arrives first from Ayton, stops at the far end of Beesville, and departs towards Ceeside. Train 2 follows Train 1 from Ayton, stops at the near end of Beesville behind Train 1, and departs later towards Ceeside. In short, two A-B-C trains which have overlapping stops at B.
  • Train 1 arrives first from Ayton, and stops at the far end of Beesville. Train 2 follows Train 1 from Ayton, stops at the near end of Beesville behind Train 1, and departs back towards Ayton. Later, Train 1 also reverses and departs back towards Ayton. In Short, two A-B-A trains which have overlapping stops at B.

These situations do not work because NIMBY trains always reserve the track to the next signal in their direction of departure after a stop. This is a safety measure to prevent trains becoming trapped by a following train, or colliding on single track lines.

In the case of two A-B-C trains, the Train 2 attempts to reserve the track through to the signal at the end of the platform, but cannot due to Train 1 already occupying that end of the platform. In the case of two A-B-A trains, Train 1 reserves the platform back towards A, preventing Train 2 from entering the platform.

It is possible to enable platform sharing in these cases by placing a balise at the entrance to the platform, overriding the platform reservation behaviour - any train will always be able to enter the platform. In the example below, a balise has been placed at the entrance to Platform 1:

PlatformSharing BaliseAtBeesville.png

For the example of two trains with A-B-C schedules, this allows Train 2 to enter the platform behind Train 1:

PlatformSharing ABCFollowing.png

This solution could theoretically be extended to any number of trains - three, four, or more trains could be timetabled into the platform, with careful selection of stopping points.

With this solution, the player must ensure precise timetabling. NIMBY will have no ability to prevent trains getting into ridiculous situations. In particular:

  • Train 2 will still attempt to enter the platform, even if it is not long enough for both Train 1 and Train 2
  • If Train 2 arrives first, Train 1 will attempt to drive through it to reach the far end of the platform
  • If another unrelated train scheduled to use the platform arrives, it will attempt to enter the platform
  • If another unrelated train is already in the platform, Train 1 and 2 will still attempt to enter the platform
  • If another train on the same line as Train 1 or Train 2 arrives (due to delays or poor scheduling), it will attempt to enter the platform

Any of these circumstances will likely result in trains colliding and the player needing to intervene.