RSSB2750 - Review of the Uff-Cullen Recommendations related to train protection systems (T1169)

Following two signal passed at danger (SPAD)-related accidents at Southall (1997) and Ladbroke Grove (1999), a joint report into train protection systems was published by Professor John Uff and the Right Honourable Lord Cullen in 2001 . The Uff-Cullen report recommended the roll out of automatic train protection, in which a system intervenes if the driver of a train is going too fast or will exceed the end of a movement authority. The train protection system envisaged to meet this recommendation was the European Train Control Systems (ETCS). It was recognised, however, that the roll out of this system was complex and expensive in comparison to the Train Protection and Warning System (TPWS) that was already available and proving to be effective. The RSSB 'AWS and TPWS Handbook' provides the following summary on TPWS: 'The purpose of TPWS is to stop the train by automatically initiating a brake demand, where TPWS track equipment is fitted, if the train has: • passed a signal at danger without authority • approached a signal at danger too fast • approached a reduction in permissible speed too fast • approached buffer stops too fast.

TPWS is not designed to prevent SPADs but to mitigate against the consequences of a SPAD, by preventing a train that has had a SPAD from reaching a conflict point ahead of the signal. TPWS does not relieve the driver of responsibility for observing signals and speed restrictions.' The Uff-Cullen report supported the accelerated rollout of TPWS as an interim measure and envisaged that TPWS would be followed by the deployment of a higher level of protection due to the limited functionality and lack of a fail-safe. This would be delivered by the roll out of automatic train protection using ETCS. It was proposed this would start with higher speed, higher traffic lines, which would be complete by 2020 . To date TPWS has been very effective in helping to manage and reduce the residual risk from SPADs. From March 2003 to March 2008 the national level of underlying SPAD risk fell by around 80%. This reduction can be attributed to three major initiatives: 1. Industry-wide focus on the risk from SPADs 2. Installation of TPWS at all main aspect signals protecting junctions 3. Removal of Mark 1 rolling stock

More recently however, the residual risk from SPADs has plateaued. SPADs still remain a concern for the industry and there is currently a SPAD Risk Reduction Strategy being embedded as well as many ongoing initiatives to help reduce this risk further. In terms of progress in fitting automatic train protection, the industry set up a national ERTMS (European Rail Traffic Management System) Programme to roll out ETCS starting with high speed lines in Control Period (CP) 4.