The challenge

Greater Anglia has recently introduced new rolling stock to its routes. From May ‘21, the new timetable assumes faster sectional running times for the new stock.

Greater Anglia were concerned that this may result in poorer performance overall compared with the December ‘19 timetable.

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What we did

Working with Greater Anglia’s performance team, we created a bespoke full (all operator) May ‘21 timetable. We used the December ‘19 timetable as the baseline, as this had a number of trains cancelled, and removed an equivalent number of services from the May ’21 timetable to ensure comparability.

What we found

The modelling showed that the May ‘21 timetable is as resilient as the December ‘19 timetable.

The May ‘21 timetable should deliver the benefit of faster journey times between London and Norwich, with fewer departure delays due to removing slam door stock and with minimal additional risk of lateness.

The modelling suggests that the May ‘21 timetable might cause longer reactionary delays between some specific locations because services are closer together and more likely to conflict. As some services are still assumed in the new timetable to be running to old stock timings such delays may be recoverable in practice

How Greater Anglia used this information

The modelling enabled Greater Anglia to plan targeted monitoring and mitigation in the locations where there might be risk of lateness.

Using SaviRPM

• We set up SaviRPM for the Greater Anglia operating area, almost 500 modelled TIPLOCs (including 178 stations) and over 3000 timetabled services (around 1,600 Greater Anglia).
• We calibrated the model against real world data, in an iterative process with the performance team. We achieved modelled delays of 66.4% on time station stops for Greater Anglia services running under the December ‘19 timetable compared to 67.1% real world on-time – creating a robust baseline for our explorations.
• We used interactive visualisations to identify areas of poor model performance until we could reproduce real world results within one or two percentage points.
• We then implemented the May ‘21 timetable in the model and compared the results with the December ‘19 baseline.

Greater Anglia valued the ability to examine results by service group and explore why some service groups were performing worse than others.

The modelled results

• The May ‘21 timetable is as resilient as the December ‘19 timetable; resulting in an equivalent number of on time station stops
• …therefore, the May 21 timetable should deliver the benefit of faster journey times but with minimal additional risk of lateness.