Last Tuesday at Basingstoke Makerspace many of the members and some visitors sat down to an interesting talk by Kevin Roche about railway signalling in the UK and its use on the new Crossrail aka ‘The Elizabeth Line’.
Crossrail will run from Reading and Heathrow through new tunnels under London to Shenfield and Abbey Wood.
Kevin explained how railway signalling had developed in the UK following a terrible rail crash at Harrow and Wealdstone in 1952 where 112 people were killed and 340 injured.
Following that crash and others several different solutions were developed to avoid similar crashes in the future. The aim being stop trains passing red signals or exceeding the recommended speed limits.
As a result, the new Crossrail service being built is required to work on railway lines equipped with several different signalling systems known as AWS, GW-ATP, TPWS, ETCS Level 2 and Trainguard MT.
After a detailed review of each system, Kevin explained that trains on Crossrail will switch automatically between three of the signalling systems as they travel along the new route. In the eastern sections they change over while in Stratford station, but in the western section they have to change over while moving.
There has been trouble, however with interfacing the older systems designed in the 1950’s with the latest technology that allows the new trains to run as many as 30 trains per hour. In the tunnels at Heathrow Interference between the new ETCS Level2 and the older GW-ATP system is being blamed.
It is thought that the line will not open now until 2020.