Or the railway from Ballybrophy to Killonan for the uninitiated.
This little used railway line (2 trains a day each way and only 1 on Sunday) runs from Ballybrophy (on the Dublin to Cork line) to Killonan – a junction just over 4 miles east of Limerick Station.
Strangely enough for such a line, it has 4 block posts on it, counting the terminal points (Ballybrophy, Roscrea, Birdhill and Killonan). Great you might think, if either of the two trains a day gets out of path, there is the ability to change crossing points.
Except that the two services a day are provided by the one unit and don’t cross anywhere on the line. In addition, whilst Roscrea and Birdhill have two platforms, the Up platform in each case is inaccessible due to no footbridge connection. This latter has become something of an IR standard at “crossing” points, rendering such locations effectively useless for crossing service trains.
In addition, in terms of crossing point location, if you were to design a railway in terms of ideal crossing points, it is unlikely you would do it in this manner. The rough mileages of the crossing points are:
Ballybrophy 0
Roscrea 10
Birdhill 42
Killonan 52
Spot the 32 mile single line section in the middle, giving Boyle to Sligo at only 28 miles a run for its money.
Given that there is full CTC at Ballybrophy and Killonan, the more sensible approach would be to install axle counters (now that track circuits are verboten) at each end of the line and operate it as one 52 mile branch. This would allow the property development company with the inconvenience of a public transport network attached to dispense with the costs of manning 2 signal cabins and associated ETS equipment.