Sharon Odetunde
Head of Partnerships, RSSB
Improving safety and resilience is a universal goal for rail in 2026. One risk area that's overdue for development is overspeeding. But in such a varied industry as rail—where every company uses different technology and strategies to tackle the problem—how can we meet a collective goal without requiring sector–wide change and significant expense?
Sharon, thank you for joining us. Overspeeding is still not well understood within the industry. Tell us about it.
On the network, trains have to adhere to set speeds just like you do on the road. Each section of track has a permissible speed, any time somebody exceeds it, risk is introduced. Overspeeding can lead to serious consequences, such as damage to infrastructure, a signal passed at danger, or a buffer stop collision, to mention a few.
Currently there is no comprehensive way of knowing where and when overspeed events occur. European Train Control System will provide a way to monitor and control speed, but there is still a long way to go for this to be rolled out nationwide.
There are systems in place, like Train Protection and Warning System, but these have their limitations.
Knowing when and where these incidents occur is important for the safety and efficiency of our network.
What are the specific 'blind spots' in our current knowledge?
The challenge is the limitations of the systems that we do have, both in terms of coverage and quality of information. It would be very expensive to implement a measurement system that covered the whole network and included trains of different ages and specifications.
This project is looking at making use of existing signalling data feeds to identify overspeed events. Through our well–established partnership with the University of Huddersfield we have started developing systems to address this challenge.
Can you share any early findings from this research?
The research to date has proved that it is possible to use existing signalling data to get a good understanding of the locations where overspeed occurs, and the severity of the event. The tool being developed uses train describer data to estimate train movements through berths and compares their average speed to speed limits. This works very well on parts on the network with consistent speed. On more complex parts of the network where line speed varies, berth travel times can be used to identify outliers.
Results have been compared to real world data, and the findings are being used to build an online tool.
While the new tool is in its pilot phase, what immediate, practical mitigations should rail operators prioritise to manage known high–risk overspeeding locations?
We've been working with operators to do deep dives on selected high–risk locations.
The team are currently working with Govia Thameslink Railway to identify overspeed occurrences for trains operated by Southern between London, Three Bridges, and Brighton. These insights will enable targeted interventions on areas of the line that see higher risk.
A very noteworthy feature of this work is around evaluating the effectiveness of operational speed restrictions.
That's really interesting. Can you tell me more?
The analysis makes it possible to identify instances where speed restrictions are not adhered to properly. Highlighting these areas can lead to much-needed investigations, ensuring that steps are taken to make restrictions more effective.
For example, the research for one of the cases looked at how well speed restrictions are adhered to. From the data it is possible to see where certain trains move through a speed restriction too quickly or where they accelerate towards the end of the effective length. The instances highlight areas where improvements can be made by doing things like relocating speed boards or updating driver briefings.
Beyond the pilot study, how do you envision the overspeeding tool evolving as part of the wider strategic collaboration with the industry?
The study has led to the development of a demonstrator tool, that will pave the way for an overspeed analysis functionality to be integrated in the Train Movement Insights platform. This work is supported by the cross-industry Overspeed Group (OSG), who are developing an industry–wide strategy to improve the management of train overspeeding. This research is an important part of that work and OSG members, who include end users from Network Rail and several train operators, are helping to ensure strategic alignment.