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UK- West Coast Main Line speedup failure

bikkuri bahn

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bikkuri bahn

An old (11 years ago) but very interesting article about the failure to raise speeds on the WCML, and how moving blocks on mainlines were still the stuff of fairytales then.  Perhaps some relevance to recent news about HS2 being threatened with cancellation.






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While true moving block is still not in use on mainlines, a similar system based on microblocks was invented and implemented in the 1930-ies and formed the base for etcs installation in hungary. The idea is that instead of large train sized blocks, you have small logical blocks. Each train can occupy a number of blocks under the train based on length and needs a number of free blocks before it based on speed and braking distance. Each microblock is nothing more than a track circuit with a settable frequency. This allows continous monitoring of all axles, rail continuity and in cab speed signalling. Lineside signals are only needed as a backup or fallback in case unequipped trains are using the line in normal block mode. This system can be controlled with conventional electromechanical systems like the integra domino, but that requires human operators to input train speed and route data by hand when setting up routes.

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So what i was saying is the technology was available, but nobody in the UK knew about it. Also if it could juggle steam trains and high speed multiple units for 80 years then it's safe to assume it will work. (the technology was updated in 1930-ies, 60-ies, 70-ies and after 2000, nowdays all train positions, speed and route info can be monitored even on the net) So the technology is there and it's up to the politicians to make a high speed line out of it

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bikkuri bahn

JR East's ATACS does use true moving blocks, and is in use on the Senseki Line.  It also controls level crossings.  Whether that line can be considered a "main line" is debatable, but the question will be moot when ATACS is introduced on the Saikyo Line in autumn 2017.



However, ATACS, like ETCS level 3, can't monitor train integrity.  Not a problem with fixed consists found on most lines, but problematic on lines with freight trains.

Edited by bikkuri bahn
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However, ATACS, like ETCS level 3, can't monitor train integrity. Not a problem with fixed consists found on most lines, but problematic on lines with freight trains.

That can be fixed with an ATACS/ETCS compatible End Of Train device hanged on the coupler of the last freight car. It can monitor position, speed, brake pressure and report them to the control center and optionally to the locomotive. This way it's very easy to detect a problem, both on board and centrally. Actually imho this dual head ETCS system was actually factory installed on Railjets...


ps: 20 years ago, the best option for a high speed west coast mainline would have been the microblock system either in analog or digital bus based form. The latter is used in Japan as the basis for many CTC systems. Today they could go with one of the more modern, fully communication based systems. The final problem however was line capacity, namely that the lines didn't have the required throughput (number of tracks and sidings) to provide even a rolling block for truely high speed trains sandwitched between slower ones. This was a capacity assessment failiure, which made the project impossible regardless of technology and this is why JR companies don't allow even high speed standard gauge freight onto the shinkansen tracks. This will change however with the new Seikan tunnel freight operation and might result in more light and high speed freight appearing on other shinkansen routes. (i'm thinking about a similar technology as the super rail cargo, only with shinkansen tracks and speeds)

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