In the late 80s when I assume 140mph running was first mooted on the ECML was in cab signalling even dreamt of? Surely if the capable rolling stock was built, then was this high speed running more than a pipe dream and was in fact a serious ambition, with the boffins at BR believing the fifth aspect would have been sufficient to provide the necessary sighting.
I suppose I'm just wondering how serious an ambition it was and if they believed it could happen with conventional signalling. Seems crazy to build 140 mph stock without sorting the infrastructure first. A failing of BR I suppose.
To achieve 140mph (240km/h) running there is a lot to do:
- upgrade signalling to ETCS
- upgrade track quality and structures (underbridges etc) for higher speed and track forces, and remove level crossings
- upgrade OHLE (heavier cross-section, constant height)
- update the rule book (safety standards are much higher than they were 25 years ago)
All that assumes that the trains themselves (class 80x and possibly 390s) are fully compliant.
The ECML has ETCS planned south of Doncaster, but is otherwise a 125mph route bar the test section.
The GWML has the track/OHLE in hand, and ETCS will follow.
The WCML is supposedly already fit for 140mph in places (eg TV4) and has TASS rather than ETCS, but NR has never confirmed the capability.
HS2 means they won't be encouraged to implement 140mph south of Crewe, and maybe not even south of York on the ECML.
Unless everything runs at 140mph you will reduce capacity.
It's worth remembering that the APT ran at these speeds over the WCML in the early 1980s.
But within 10 years the route had degraded to the point where even 125mph was not possible without almost complete renewal and upgrade, plus the requirement for in-cab signalling.
