Computer says skip stations to speed up railways

COMMUTER TRAINS that skip stations could be one way of improving the rail network, say researchers.

The aim would be to break “feedback loops” in the system that have been identified as one of the main causes of delays and cancellations.

Britain’s rail network transports more than 1.7bn passengers each year, including 1.1bn commuting in or around London.

Last year, only 86.9 per cent of passenger services arrived on time in the London area and 4.8 per cent of journeys were cancelled or significantly late, according to the Office of Rail and Road.

The computer simulation study involved reconstructing the networks of five British rail companies using real-world data.

It showed that network structure and scheduling had a much bigger impact on delays than events such as blocked tracks or signal failures.

In particular, “loops” in the system led to problems.

The study’s author, Dr Alessio Pagani, from the Alan Turing Institute in London, explained the loop idea with a triangle representing passenger flow on a train network.

At each corner of the triangle, people either worked, or lived, or were passing through. Flows around the triangle interacted, and with every “train” stopping at every “station” in the loop, there was a risk of delays cascading and building up.

The solution could be to break the loop by providing some fast services that miss one or more stations, the study suggested. Dr Pagani said: “Some train companies are better than others. What we want to show is that when train operators perform badly it may not be their fault. The problem is that there are these loops in the system that cause delays.”