John R
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« Reply #30 on: December 02, 2008, 19:00:11 » |
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If only it were that easy. Elf'n safety probably means that the bay will need to be rebuilt to modern standards as it is "new". And I expect the signalling does not meet the requirements for passenger services.
As far as I understand the existing formation is still in place, although between Milton and Weston a footbridge (?) has blocked the second line, so would need to be replaced. Hence it's more costly and thus phase 1 ends north of Milton (and also avoids rebuilding the second platform there, which is currently in service at Lympstone Commando and has been for the last 30 years or more.)
I don't think the problem is platform space at Weston - more that in the peak, trains are timed so that as soon as one leaves the single track another occupies it. Thus there is no margin for any delays without knock on effects.
For example, in the current timetable, trains leave Weston at 0733 and 0750 towards Bristol, but inbetween a train is timetabled to leave Worle at 0741 and arrive at Weston at 0746. Some other services are timed to arrive at Weston at the same time as one is departing, such as the 0725 (Plymouth to London), which relies on a 0725 arrival from Severn Beach being on time. If the 0725 arrival is held because it is late then it certainly won't be able to make its 0733 departure return working, causing further delays.
So in the peak the service is on a knife edge, and the additional flexibility of dualling the junction and onward to Milton would give a useful margin, as well as presumably giving timetable planners a bit more leeway.
Sorry if this is all a bit detailed!
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ReWind
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« Reply #31 on: December 02, 2008, 21:27:26 » |
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If Worle Jnc to Milton was redoubled then that would provide relief for services waiting to enter the line to Weston but if the current single line was to be redoubled, I still couldn't see any room for extra capacity, more trains from BTM▸ to Weston as the line from Parson Street to Worle, currently 2 tracks is currently at or near capacity anyway.
If more trains were to run from BTM to Weston then they would cause problems and delays to the fast XC▸ services that use this stretch of line.
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Here, there and Everywhere!!
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Zoe
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« Reply #32 on: December 02, 2008, 21:37:17 » |
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If Worle Jnc to Milton was redoubled then that would provide relief for services waiting to enter the line to Weston but if the current single line was to be redoubled, I still couldn't see any room for extra capacity, more trains from BTM▸ to Weston as the line from Parson Street to Worle, currently 2 tracks is currently at or near capacity anyway.
The London to South West & South Wales Multi-Modal Study (SWARMMS) recommended the provision of passing loop facilities at a location between Worle and Nailsea. http://www.swarmms.org.uk/documents/PLANBris-Exev2.pdf
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John R
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« Reply #33 on: December 02, 2008, 22:49:47 » |
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If Worle Jnc to Milton was redoubled then that would provide relief for services waiting to enter the line to Weston but if the current single line was to be redoubled, I still couldn't see any room for extra capacity, more trains from BTM▸ to Weston as the line from Parson Street to Worle, currently 2 tracks is currently at or near capacity anyway.
The London to South West & South Wales Multi-Modal Study (SWARMMS) recommended the provision of passing loop facilities at a location between Worle and Nailsea. http://www.swarmms.org.uk/documents/PLANBris-Exev2.pdfI think the idea of dualling is to make the existing service more robust, not to add additional services. Passing loops do exist between Worle and Yatton, and were upgraded for passenger train use a couple of years ago. They are usually used sensibly in the event of late running services, though not always. And nearer Bristol, if an up fast service is breathing down the neck of a stopping service then the latter will be routed onto the relief lines after Parson St. The result is that (although it is due to stop at Parson St) the signalling almost brings it to a halt short of Parson St and slows it by around a minute before it even calls at the station. Only then, after the station call can it switch onto the relief line. Result, even further delay for (usually) the XC▸ service. A fast turn out before Parson St would remove this, but it all costs more money, years of planning, and will never be done.
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devon_metro
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« Reply #34 on: December 03, 2008, 16:13:11 » |
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If Worle Jnc to Milton was redoubled then that would provide relief for services waiting to enter the line to Weston but if the current single line was to be redoubled, I still couldn't see any room for extra capacity, more trains from BTM▸ to Weston as the line from Parson Street to Worle, currently 2 tracks is currently at or near capacity anyway.
The London to South West & South Wales Multi-Modal Study (SWARMMS) recommended the provision of passing loop facilities at a location between Worle and Nailsea. http://www.swarmms.org.uk/documents/PLANBris-Exev2.pdferrr whatever happen to Yatton loop :?
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bemmy
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« Reply #35 on: December 06, 2008, 08:44:43 » |
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And nearer Bristol, if an up fast service is breathing down the neck of a stopping service then the latter will be routed onto the relief lines after Parson St. The result is that (although it is due to stop at Parson St) the signalling almost brings it to a halt short of Parson St and slows it by around a minute before it even calls at the station. Only then, after the station call can it switch onto the relief line. Result, even further delay for (usually) the XC▸ service. A fast turn out before Parson St would remove this, but it all costs more money, years of planning, and will never be done.
It's a shame they couldn't have done this when the work was being done to re-open the Portbury freight line. But that would involve integration between work for freight and passenger purposes, which I believe is what they call "joined up thinking" and therefore practically illegal.
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bemmy
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« Reply #38 on: January 15, 2009, 16:49:43 » |
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Surely a Tory MP▸ complaining about the shortfall in railway provision is a bit like King Herod bemoaning the lack of firstborn children.
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Lee
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« Reply #39 on: January 15, 2009, 16:58:14 » |
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No worries, thanks for posting one that works.
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G.Uard
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« Reply #40 on: January 16, 2009, 09:17:37 » |
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Surely a Tory MP▸ complaining about the shortfall in railway provision is a bit like King Herod bemoaning the lack of firstborn children.
Love it! Completely off topic I know...but in Greece, when kids misbehave, parents often say that King Herod was the most misunderstood man in the Bible.
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inspector_blakey
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« Reply #41 on: January 16, 2009, 23:25:44 » |
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When is the average backwoods politico going to realise that it's not just a matter of popping down to 'Carriages R Us'? Or am I being naive in not recognising this as a clumsy and transparent attention grabber?
Absolutely right. Bleating about public transport and giving the railways a kicking does seem to be a speciality of witless local politicians and the equally witless local journos who'd rather sit on their backsides and pick their noses than go out and report on some actual news. Then again, we are talking about Weston in January. I suppose there can only be so much happening there
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devon_metro
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« Reply #42 on: January 17, 2009, 00:10:59 » |
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Do half hourly hsts ( in general) at peak time not provide enough capacity?
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simonw
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« Reply #43 on: January 17, 2009, 00:30:58 » |
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It depends on the number of passengers and carriages!
After all Reading has 8 HSTs▸ per hour to London, and about 4 local trains and they still packed.
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John R
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« Reply #44 on: January 17, 2009, 10:28:39 » |
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Do half hourly hsts ( in general) at peak time not provide enough capacity?
In the morning, yes. In the evening they are only hourly, and so there is a serious imbalance in the number of seats provided, resulting in considerable overcrowding.
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