Rail Engineer has devoted many column inches to ETCS but mostly about its cost and deployment issues. ETCS is much more than a signalling system as it requires information about train formation, loads, and other characteristics. Inevitably, for a new system, some of these requirements might conflict with current national practice. It has been suggested that national practice should be changed in order to deliver the benefits of the inter-operable system. However, this is easier said than done, and resolving these issues takes time and money which is one reason why the first installations might cost more than the production run.
Some of those issues discussed here, if not addressed, could hamper operation of some types of train and could lead to some classes of locomotive being prohibited altogether. Partly this is as a result of Great Britain’s flexibility in what vehicles it allows to run where and partly because important aspects of GB practice were not incorporated into the standards/specifications. The risk is that lowest common denominator default values could be used, leading to a significant reduction in network capacity compared with the current lineside signalled railway with its rules and signage.
Rail Engineer understands that a paper outlining the issues was presented to the Office of Rail and Road (ORR) in early 2019. These are system issues that need to be captured in ETCS but cannot be resolved by signalling engineers alone. Network Rail and the ORR were asked for comment. Network Rail gave some useful feedback which is reproduced in full.
The issues are:
- Braking values for various train formations.
- Axle load categorisation for bridge loading.
- Implementation of differential speed limits.
- Cant deficiency rounding.
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