Post by mrfs42 on Dec 20, 2011 8:19:50 GMT
Quite simply untrue - it has improved of late in the light of experience, but AFAIAA there is still the need for a technician to travel with a unit at least once a week. This is an improvement on whenever a train is in service.
Movement authorities are delayed - there is a incident under investigation by the RAIB about Llanbadarn crossing, I've experienced several times grinding to a halt at what would be the 'advanced starter' - ie quite a way into the section after a crossing because the interrogation of the eurobaliises hasn't registered at the shoebox in Machynlleth. Eurobalises can only be interrogated on the move: did you realise that Pwllheli and Aberystwyth are the first terminii in the world to be signalled under this scheme?
The specifications for ERTMS have been rewritten so the source document is vastly different from that as originally envisaged: reversible road working, leading vehicle not ETRMS fitted, degraded mode working derogations... The list goes on. Have you seen ERTMS resignalling? I really don't want to name drop, but written by a good acquaintance of mine - is the impression that 'the testing was going really rather well' perhaps some hyper-positive spin put out to counteract the unusual occasion of a manager being very frank and honest?
ERTMS could be a true low-cost signalling system, if it works; I'm sure that it could by now be regarded as intrinsically safe, but only by dint of the fact that it brings everything to a stand when communication is lost. I do not expect it to offer full bidirectional capability for Crossrail (heading back towards the subject) without yet another visit to the specifications.
I'm not a huge fan of recommending other fora, but I would suggest that you look at Cambrian ERTMS; there's 17 pages of discussion there - read that and I hope you still have a positive impression of ERTMS.