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Post by MoreToJack on Jun 16, 2019 15:32:22 GMT
I don’t think that Metropolitan line trains would exceed their current top line speeds given that SelTrac S40 itself is limited to 108kmh / 67mph. The Dubai metro uses a similar variant of S40 to what is being installed on the SSR and it tops out at 62mph even though the rolling stock is capable of much more. spsmiler , I hope the run from Kings X to Farringdon isn’t lifted any further given that it would mean a sharp brake for the curves over the Widened Lines East and likewise past the disused MET platforms East. Even at 40mph which is the current speed, you will rarely get a train maxing out during the peak periods, a 50mph+ would surely start to eat away at capacity. A linespeed increase in this area is indeed planned, and test trains have operated under Seltrac at 50mph. Whether it uses it in practice, of course, is another thing entirely - the congestion through the City would suggest not (and is what makes me very dubious of any frequency increases on the top side of the Circle; signal spacing isn't the only constraint to that congestion).
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Post by 35b on Jun 16, 2019 15:54:42 GMT
S stock are limited to 62mph although I wonder if that could be increased? I’m not sure that I would want to travel at 70mph on those little wheels! These trains are really meant for short distance urban journeys where acceleration is of greater importance than top speed. Especially the Metropolitan Main Line fast services would benefit more from trains designed for higher top speeds, as greater acceleration is of lesser importance on journeys where the inter-station journey times can be 5 minutes and even more. The Chiltern diesels can do at least 90 mph, possibly even 100 mph - this being the upper speed in the route to Birmingham which was recently revamped and brought closer to present-day speed expectations for main lines that are not High Speed lines. You only have to look at the situation on the roads (numbers of people caught 'speeding') to know that people do value faster travel and its only those who take decisions (or ride pedal bikes) who favour slowness. The railways of course are the safest way to obtain the desired higher speeds. To make the topic of travelling speed directly relevant to SSR resignalling, I recall a mention a while ago about how automation will see a significant rise in the the speed limit between Farringdon and Kings Cross to 52 mph, reducing the journey time quite noticeably. I thought the class 165/0 units were limited to 75. Even if not, my experience on a recent trip was that the top speed was not the primary issue for speed.
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Post by superteacher on Jun 16, 2019 18:22:58 GMT
I don’t think that Metropolitan line trains would exceed their current top line speeds given that SelTrac S40 itself is limited to 108kmh / 67mph. The Dubai metro uses a similar variant of S40 to what is being installed on the SSR and it tops out at 62mph even though the rolling stock is capable of much more. spsmiler , I hope the run from Kings X to Farringdon isn’t lifted any further given that it would mean a sharp brake for the curves over the Widened Lines East and likewise past the disused MET platforms East. Even at 40mph which is the current speed, you will rarely get a train maxing out during the peak periods, a 50mph+ would surely start to eat away at capacity. A linespeed increase in this area is indeed planned, and test trains have operated under Seltrac at 50mph. Whether it uses it in practice, of course, is another thing entirely - the congestion through the City would suggest not (and is what makes me very dubious of any frequency increases on the top side of the Circle; signal spacing isn't the only constraint to that congestion). I suppose it’s handy in order to recover a bit of late running. But as you allude to, the opportunity to use it in practice with a minimum 24 tph service for most of the day will be limited.
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metman
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Post by metman on Jun 16, 2019 21:34:00 GMT
These trains are really meant for short distance urban journeys where acceleration is of greater importance than top speed. Especially the Metropolitan Main Line fast services would benefit more from trains designed for higher top speeds, as greater acceleration is of lesser importance on journeys where the inter-station journey times can be 5 minutes and even more. The Chiltern diesels can do at least 90 mph, possibly even 100 mph - this being the upper speed in the route to Birmingham which was recently revamped and brought closer to present-day speed expectations for main lines that are not High Speed lines. You only have to look at the situation on the roads (numbers of people caught 'speeding') to know that people do value faster travel and its only those who take decisions (or ride pedal bikes) who favour slowness. The railways of course are the safest way to obtain the desired higher speeds. To make the topic of travelling speed directly relevant to SSR resignalling, I recall a mention a while ago about how automation will see a significant rise in the the speed limit between Farringdon and Kings Cross to 52 mph, reducing the journey time quite noticeably. I thought the class 165/0 units were limited to 75. Even if not, my experience on a recent trip was that the top speed was not the primary issue for speed. The 165/0 are limited to 75mph but could be modified to run at 90mph like there cousins and class 166 on the GWR. I certainly feel that acceleration is more important than top speed on the Circle. As said it’s the flat junctions that limit matters. Even with computers there is only a certain amount of frequency possible.
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North End
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Post by North End on Jun 16, 2019 23:08:09 GMT
A linespeed increase in this area is indeed planned, and test trains have operated under Seltrac at 50mph. Whether it uses it in practice, of course, is another thing entirely - the congestion through the City would suggest not (and is what makes me very dubious of any frequency increases on the top side of the Circle; signal spacing isn't the only constraint to that congestion). I suppose it’s handy in order to recover a bit of late running. But as you allude to, the opportunity to use it in practice with a minimum 24 tph service for most of the day will be limited. Modern trains can get up to speed pretty quickly - even the Northern manages to get up to 45 mph in the very short Warren Street to Goodge Street section (shame about all those bits elsewhere where speed is now slower than before the upgrade!). So it’s quite possible 50 mph or even a bit more could be attained between Farringdon and King’s Cross if the speed profile allows it. However I generally agree that the density of this section will quite likely conspire against this, the train may well get a high target speed but soon be braking down again. For those who like a fast run, the Jubilee or Victoria lines are probably the best bet, mainly if the train is running late. Stockwell to Kings Cross can now be achieved in as little as 12 minutes in the right circumstances. The Northern has too many lower speed limits in places to provide a sparking run, the Charing Cross branch perhaps being the exception - ironically this was the slowest section pre-upgrade.
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rincew1nd
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Post by rincew1nd on Jun 16, 2019 23:11:36 GMT
I suppose it’s handy in order to recover a bit of late running. But as you allude to, the opportunity to use it in practice with a minimum 24 tph service for most of the day will be limited. However I generally agree that the density of this section will quite likely conspire against this, the train may well get a high target speed but soon be breaking down again. Breaking down because they can't cope with the speed, it braking down to the station stop? Or both? Do'nt you love pedants'
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North End
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Post by North End on Jun 16, 2019 23:13:28 GMT
However I generally agree that the density of this section will quite likely conspire against this, the train may well get a high target speed but soon be breaking down again. Breaking down because they can't cope with the speed, it braking down to the station stop? Or both? Do'nt you love pedants' Seems like auto correct has interfered there. You’re quite right I meant braking down...
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Post by philthetube on Jun 17, 2019 11:44:47 GMT
I see that a significant portion of the District line is closed this coming weekend, will that be for CBTC testing? if so, might this explain why the four track route has replacement buses rather than Piccadilly line trains using District line tracks? Moving further afield, re: interoperable areas on the Met Main Line, would I be right in assuming that only the mainline north of Harrow-OT-Hill will be interoperable (since Chiltern trains can not access the local line?) One other question, maybe though the answer is 'why bother asking' or 'we will address that issue if / when it is built' but anyway, here goes. On the off-chance that the Croxley link does actually somehow become funded, will it (and the North Curve) also be signalled as an interoperable line? After all, it was mooted that Chiltern would possibly be interested in an Aylesbury - Watford Junction service!
An an aside, Chiltern's franchise will be up for renewal in 2021. I wonder if electrification will be on the cards? Restoration of higher line speeds, indeed, raising even higher than before - possibly to 90mph? 100mph? (Obviously not at Rickmansworth station) A desire for LU to fit AWS / ATP equipment so that Tripcocks wont't be needed? I am also aware of developments further north of Aylesbury that might affect the Chiltern service that travels along the joint line (East West rail reopening, more...)
Thanks Simon I was under the impression that train stops were to be replaced with AWS equipment as this is much cheaper to maintain. (Only heard it on the grape vine though so probably wrong) I don't think the current Chiltern stock has the ability to climb from Rickmansworth to Amersham any quicker than it does, an S stock following one certainly has to dawdle, also not sure about the braking capabilities, especially during leaf fall on the downhill journey. If Chiltern services are ever electrified I imagine dual voltage trains would be used with overhead power supplies Amersham north and Harrow South.
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Post by spsmiler on Jun 17, 2019 12:33:10 GMT
I think it's the local inhabitants bringing pressure to bear on the decision makers in the area - although when those inhabitants get in their cars they are often caught by the speed cameras they themselves campaigned for. Observation of cyclists' behaviour suggest many of them are very much in favour of speed. I agree with your comment about those who advocate enthusiastic enforcement of slowness then often becoming ensnared by the very traps they wanted. Speed limits don't apply to cyclists - they just want everyone else to travel below 20 mph. Many years ago I recall reading about speed cameras and speed traps on the subsurface railway - in the C stock era, on the Hammersmith & City near to Paddington station. -------------- Over the past few weeks I've been (slowly) making a film about the SSR automation. Finally this has been completed. Apologies for its length (almost 11 minutes) but I still had to remove some things that would have been nice to include, such as what trainstops are (where I refer to switching the train back to the legacy 'human driving with colour light signals & tripcocks' mode) and that its Wimbledon branch passengers who feel that other routes get preferential treatmentI also did not go into detail any of the history that explains why SSR trains share tracks with other trains, where this no longer happens, etc - I would have used my footage of a GWR City Stock carriage at the Didcot Railway Centre - and even though I dont have any visuals was also originally planning to mention the Southend Corridor Express. Seeing the S stock train on the fast line at Northwood was an unexpected bonus filmed when the first C stock train was taken there for scrapping. If I had been ready for its passing I would have even had the camera out when I first saw it and held it more steady.
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Post by Dstock7080 on Jun 17, 2019 13:02:41 GMT
Many years ago I recall reading about speed cameras and speed traps on the subsurface railway - in the C stock era, on the Hammersmith & City near to Paddington station. Random speed monitoring is undertaken by DRM Duty Reliability Managers on a regular basis at particular high-risk locations, using hand-held monitors. There are also speed controlled signals which will not clear until the trains speed has been lowered to match the required speed limit. Too slow is also taken into account at some locations.
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Post by norbitonflyer on Jun 17, 2019 14:18:25 GMT
Speed limits don't apply to cyclists - they just want everyone else to travel below 20 mph. With the speed limiter in my car set to the 20mph speed limit in Richmond Park, I am frequently overtaken by cyclists bent on improving their lap times - even though the speed limit set by Royal Parks bylaws applies to cyclists and horse riders as well as motorists.
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Post by MoreToJack on Jun 17, 2019 15:14:04 GMT
Unless I’m mistaken, cyclists don’t ride on railway tracks. Back to the topic in hand, please.
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Post by Deleted on Jun 17, 2019 15:48:20 GMT
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rincew1nd
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Post by rincew1nd on Jun 17, 2019 16:21:53 GMT
Will that be compatible with the new signalling?
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Deleted
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Post by Deleted on Jun 17, 2019 16:51:29 GMT
As long as it got metal wheels take them rubber tyres off and the system would still be compatible with the axle counters
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class411
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Post by class411 on Jun 17, 2019 17:47:04 GMT
Does anyone know why the eastbound train describers at stations near the Hammersmith end of the HC&C line are so intermittent?
Very occasionally they show an actual destination and time, but more often say 'check front of train', or the hugely useful 'Hammersmith and City Eastbound'.
The westbound indicators seem to work well (although it's not the most difficult of jobs getting the destination correct).
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Tom
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Post by Tom on Jun 17, 2019 18:22:20 GMT
The Chiltern diesels can do at least 90 mph, possibly even 100 mph - this being the upper speed in the route to Birmingham which was recently revamped and brought closer to present-day speed expectations for main lines that are not High Speed lines. (snip) To make the topic of travelling speed directly relevant to SSR resignalling, I recall a mention a while ago about how automation will see a significant rise in the the speed limit between Farringdon and Kings Cross to 52 mph, reducing the journey time quite noticeably. I'd actually disagree with you on a couple of points. Whilst a class 168 can achieve 100mph, a class 165 (at least a Chiltern 165/0) can only achieve 75mph. With regards to the speed limit between KX and Farringdon, whilst it will be possible to attain 52mph, the weakness in the argument that it will reduce journey times is that transit time between two places is limited by (a) the dwell time at the following station and (b) how many trains LU chooses to inject into a particular run. The line speed in this area today is 40mph, but as soon as a train sits down in Farringdon platform the following train is subjected to a reduced speed approach, eventually being held at OH47 B; just off the platform. In the peaks, it's not uncommon to have a queue of trains waiting to get past Aldgate Junction, and this frequently causes blocking back as far as Farringdon. Indeed, I spent the early part of 2013 commissioning various modifications to try and alleviate this problem (or at least to stop it being exacerbated by the introduction of S7s). I very much doubt that the introduction of CBTC will have a noticeable effect on journey times in the city other than very early in the morning or very late at night - once past Farringdon the stations are so close together that a decently high speed is rarely attainable and the queuing of trains and long dwell times at Liverpool Street, Farringdon and King's Cross will continue to be the limiting factors in capacity that an increase in line speed alone cannot overcome. EDIT: Looks like everyone else beat me to it and made much the same observations. Never mind...
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Tom
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Post by Tom on Jun 17, 2019 18:26:50 GMT
Does anyone know why the eastbound train describers at stations near the Hammersmith end of the HC&C line are so intermittent? I thought that other than at Hammersmith (where their interface to the CBTC hasn't been as good as when they were controlled by the Mk1 Human) they'd actually got better.
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Post by d7666 on Jun 18, 2019 11:43:39 GMT
Does anyone know why the eastbound train describers at stations near the Hammersmith end of the HC&C line are so intermittent? I thought that other than at Hammersmith (where their interface to the CBTC hasn't been as good as when they were controlled by the Mk1 Human) they'd actually got better. "check front of train" at Goldhawk Road EB has been very common over the past 3 weeks (except last week when I was away from commuting) or so in my travel experience. It started out well on CTBC but seems like something has changed.
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Post by spsmiler on Jun 28, 2019 21:38:27 GMT
Today I saw a message on a railgen website saying that the next CBTC migration area will tested in mid July and if all goes well will be brought into full-time use in August.
The section of railway being talked about is Latimer Road and Finchley Road to Euston Square.
Is this correct?
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Deleted
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Post by Deleted on Jun 28, 2019 21:51:54 GMT
Correct
Aka SMA1 and SMA 2
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Post by t697 on Jun 29, 2019 9:06:23 GMT
Does anyone know why the eastbound train describers at stations near the Hammersmith end of the HC&C line are so intermittent? Very occasionally they show an actual destination and time, but more often say 'check front of train', or the hugely useful 'Hammersmith and City Eastbound'. The westbound indicators seem to work well (although it's not the most difficult of jobs getting the destination correct). The default to "Check front of train" is used widely on LUL platform DMIs when things go wrong. A suggestion to fit the trains with a destination of "Check platform indicator" wasn't popular... Sorry, back to the topic.
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Post by goldenarrow on Jun 29, 2019 11:33:15 GMT
Does anyone know why the eastbound train describers at stations near the Hammersmith end of the HC&C line are so intermittent? Very occasionally they show an actual destination and time, but more often say 'check front of train', or the hugely useful 'Hammersmith and City Eastbound'. The westbound indicators seem to work well (although it's not the most difficult of jobs getting the destination correct). This is a symptom of the constant tweaks that are being made to train describers both over the API (Application Programming Interface) streams that are available on the TfL Website/3rd party apps and the stations themselves which to my understanding run directly off the signalling system. The API is completely blown at the moment for the Hammersmith branch with only Shepherds Bush Market fully working. This information black hole that made the Hammersmith Branch infamous will pop up in other places as zones migrate. I guess its and inevitability when juggling with different systems some of which have unique quirks of their own.
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Post by 35b on Jun 29, 2019 16:21:34 GMT
Does anyone know why the eastbound train describers at stations near the Hammersmith end of the HC&C line are so intermittent? Very occasionally they show an actual destination and time, but more often say 'check front of train', or the hugely useful 'Hammersmith and City Eastbound'. The westbound indicators seem to work well (although it's not the most difficult of jobs getting the destination correct). This is a symptom of the constant tweaks that are being made to train describers both over the API (Application Programming Interface) streams that are available on the TfL Website/3rd party apps and the stations themselves which to my understanding run directly off the signalling system. The API is completely blown at the moment for the Hammersmith branch with only Shepherds Bush Market fully working. This information black hole that made the Hammersmith Branch infamous will pop up in other places as zones migrate. I guess its and inevitability when juggling with different systems some of which have unique quirks of their own. You mean a critical system has been deployed when not actually fit for use? It was not giving any useful information at Paddington eastbound last Saturday, causing confusion amongst the tourist hordes and blocking the platform.
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Post by Chris L on Jun 29, 2019 18:08:46 GMT
Correct Aka SMA1 and SMA 2 Will trains heading to Edgware Road from Paddington (D&C) have to transition to the new system for a short section?
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Post by Deleted on Jun 29, 2019 19:08:15 GMT
Yes I believe so perhaps a District or Circle driver could confirm the arrangements at Paddington
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Post by Dstock7080 on Jun 29, 2019 19:34:22 GMT
Will trains heading to Edgware Road from Paddington (D&C) have to transition to the new system for a short section? Yes I believe so perhaps a District or Circle driver could confirm the arrangements at Paddington Yes indeed they will. “Check VOBC” signage at Bayswater, with the actual boundary point at Paddington. Trains will work in CBTC into and out of Edgware Road.
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Post by goldenarrow on Jun 29, 2019 21:48:35 GMT
35b , The product itself that Thales is providing for train description is tried and tested enough (I think it is actually one of the oldest parts of the SelTrac product). However as Bombardier and Siemens are finding out with Crossrail , systems integration is raley clean cut with brand new projects let alone with legacy systems. I'm sure there are dozens of little quirks that still lie in the remaining parts of conventionally signalled sections from redundant description codes to ad hoc forms of offering up train descriptions to the next centre/cabin of control.
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Post by 35b on Jun 30, 2019 6:47:06 GMT
35b , The product itself that Thales is providing for train description is tried and tested enough (I think it is actually one of the oldest parts of the SelTrac product). However as Bombardier and Siemens are finding out with Crossrail , systems integration is raley clean cut with brand new projects let alone with legacy systems. I'm sure there are dozens of little quirks that still lie in the remaining parts of conventionally signalled sections from redundant description codes to ad hoc forms of offering up train descriptions to the next centre/cabin of control. Understood. But I didn’t refer to Seltrac alone, but the entire system, which includes the bits that interface with it.
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Post by zcap on Jul 2, 2019 19:00:08 GMT
Hey all,
I was in Farringdon earlier and noticed that the Outer to Inner circle line points were removed!
When was this work done?
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