Elizabeth Line / Crossrail Updates.

[Suzie]

Can someone please explain NNML to me I don't think the North Norfolk goes that far.

 

Jamie

 

New North Main Line? The former GWR main line from Paddington to Birmingham that is now just a 'Parliamentary' between Old Oak Common and South Ruislip. Built as double track with non-platform avoiding lines at stations to allow expresses to pass stoppers.

[Christopher125]

Can someone please explain NNML to me I don't think the North Norfolk goes that far.

 

Jamie

Sorry, I'm referring to the lightly used connection between the GWML at Old Oak Common and the Chiltern Mainline via North Action and Greenford.

 

The logical think with Crossrail if a northern route is in mind is simply to keep it on the north side of the Relief Lines - easy to provide a separate pair of running lines all the way to Old Oak for trains which will reverse there thus keeping them completely clear of the relief Lines although obviously Crossrail trains joining the Relief Lines to head west will have to cross the Up Relief somehow which would involve slewing the Reliefs if a flying junction is in mind (but as there's no sign of it as yet i presume a flat junction will be the initial situation?.

AFAIK there are no plans for a second pair of tracks, the plan always being for Crossrail trains to have a pair of central turnback sidings/platforms at Old Oak Common between the relief lines.

 

This diagram and visualisation shows what is planned.

Edited August 12, 2016 by Christopher125

[jamie92208]

Thanks for the two replies explaining the NNML. I have actually been over it on the parliamentary service from Paddington. The guard said that most of his passengers rom Paddington were doing it to get the trackage.

 

Jamie

[The Stationmaster]

Sorry, I'm referring to the lightly used connection between the GWML at Old Oak Common and the Chiltern Mainline via North Action and Greenford.

 

 

AFAIK there are no plans for a second pair of tracks, the plan always being for Crossrail trains to have a pair of central turnback sidings/platforms at Old Oak Common between the relief lines.

 

This diagram and visualisation shows what is planned.

 

Blimey - that's a gradient of c.1 in 58 or worse   (the Up Relief Line will have to climb a vertical height of 30ft minimum in a running distance of 1716ft).  Sounds like it was designed by a raving loony.

 

I'm still trying to puzzle out what those of us in some parts of the Thames Valley have doen to upset the transport planners of London as every single idea they come up with seems to be increasing our journey time to get there.  Far simpler and a lot cheaper to keep Crossrail on the north side.

[Christopher125]

Blimey - that's a gradient of c.1 in 58 or worse (the Up Relief Line will have to climb a vertical height of 30ft minimum in a running distance of 1716ft). Sounds like it was designed by a raving loony.

I can't see the problem with a short sharp gradient, well within the capabilities of modern EMUs, on the approach to a station.

[sng7]

Blimey - that's a gradient of c.1 in 58 or worse   (the Up Relief Line will have to climb a vertical height of 30ft minimum in a running distance of 1716ft).  Sounds like it was designed by a raving loony.

 

Wouldn't be a problem, queen street tunnel is 1 in 42 and modern units have no problem with it so 1 in 58 wouldn't be an issue

[Zomboid]

The question is really what else would have to get over it? The passenger stock should be OK, but will anything else regularly pass?

[phil-b259]

The question is really what else would have to get over it? The passenger stock should be OK, but will anything else regularly pass?

 

Given the location of the proposed flyover is after the connection between the NLL and the GWML, the only thing going over it will be Crossrail EMUs (unless someone opens a cement / stone terminal on the Paddington approaches like the one just outside St Pancras). Its a different situation to the west however where heavy freights to / from Acton yard will be mixed in with said EMUs.

[The Stationmaster]

The question is really what else would have to get over it? The passenger stock should be OK, but will anything else regularly pass?

 

Exactly so.  Engineering trains are an obvious one so 1,500 tonnes of something or other might, or might it, make it easily - definitely not going to be easy with that gradient and the curvature but a Cl.70 should be ok.  I'nm not so sure quite how a 12  coach loco hauled train might or might not do but it certainly won't go up it very fast and a  steam special is likely to be somewhat slower.  Picking up Phil's point whether or not the stone terminal will reopen is another matter as I'm not sure if there would still be space for it following various land sales between Westbourne Park and Royal Oak.  Incidentally it won't just be Crossrail trains going over it anyway as there is supposed to a continuing GWR presence on the Reliefs due to lack of capacity on the Mains and the likelihood of two GWR trains per hour serving Ealing Broadway although timetable details are still far from settled.

 

Any idiot can design a  gradient profile for a  single form of traction - mixed traffic and 'oops I didn't think of that comes a bit harder'.

 

But to be honest I still can't see the point of it - the only thing it seems to offer (for a very large sum of money) is cross platform interchange with Crossrail trains and that can just as readily take place at Ealing Broadway.  It doesn't do anything to sort Down Crossrail trains crossing over the Up Relief - which is likely in any event to be the most frequent conflict and the biggest pinch on capacity - while at the same time as all the depot areas are going it would be simple to keep Crossrail on a northern pair of lines with a station which could be opened completely separately (suitably aligned) long before anything else needs to be built.  That way no Crossrail trains reversing at Old Oak or going to any putative 'northern' branch will conflict with anything other than themselves all the way from the tunnel mouth to Old Oak Common West.

[The Evil Bus Driver]

Thanks for the two replies explaining the NNML. I have actually been over it on the parliamentary service from Paddington. The guard said that most of his passengers rom Paddington were doing it to get the trackage.

 

Jamie

Yep. When I did it he checked tickets to relieve the boredom.

Edited August 13, 2016 by The Evil Bus Driver

[HillsideDepot]

I hadn't thought about the Old Oak station before, but seeing the visualisations linked to above it could (will?) be a major change for the GWML.

I assume from the plans that all inter-city trains will call there, and with connections onto Cross-Rail, Heathrow, HS2, maybe the WCML and Chiltern line (Underground & Overground should be within travelator/dedicated monorail type link distance too) why wouldn't they, meaning that Paddington will almost become a carriage siding with public access! A London version of Malago Vale or Goodrington.

 

It's taking a while to get my mind around that!

[The Stationmaster]

I hadn't thought about the Old Oak station before, but seeing the visualisations linked to above it could (will?) be a major change for the GWML.

 

I assume from the plans that all inter-city trains will call there, and with connections onto Cross-Rail, Heathrow, HS2, maybe the WCML and Chiltern line (Underground & Overground should be within travelator/dedicated monorail type link distance too) why wouldn't they, meaning that Paddington will almost become a carriage siding with public access! A London version of Malago Vale or Goodrington.

 

It's taking a while to get my mind around that!

 

The interesting thing which comes out of that is what impact it might have on travel patterns?

 

The change to Crossrail from GWML would be easier at Old Oak - assuming the footbridge is wide enough to handle large numbers of people but that really is about it.  Many people travelling via Paddington use the District/Circle Lines while a large majority travel onwards via the Bakerloo and unless changing trains twice gives a significant time gain they're unlikely to change to Crossrail except for those heading for the Oxford St area  (Piccadilly Circus is the debatable destination).  HEX will still operate from Paddington and represents probably the quickest way to the airport if you don't change to the western link at Reading once it's up & running - it will definitely remain the best option for those with larger pieces of luggage.

 

The big advantage of Old Oak would be for people who currently go from Paddington to Euston and possibly KX but in reality they are travelling largely from east of Newbury/Reading and would be served by GWR semif-fasts.

 

There is of course a market in the opposite direction - probably more diverse in origin and then with many London originators it depends what facilities the station offers compared with Paddington; passenger choice being influenced by far more factors than a handy (it would appear) place to change trains.

[Christopher125]

Exactly so.  Engineering trains are an obvious one so 1,500 tonnes of something or other might, or might it, make it easily - definitely not going to be easy with that gradient and the curvature but a Cl.70 should be ok.  I'nm not so sure quite how a 12  coach loco hauled train might or might not do but it certainly won't go up it very fast and a  steam special is likely to be somewhat slower.

I can't imagine the flyover will prove as big an obstacle to pathing if not bigger than fitting such trains between all the electric Crossrail and GWR services - it won't be easy but that's for running such trains into any London termini.

  

But to be honest I still can't see the point of it - the only thing it seems to offer (for a very large sum of money) is cross platform interchange with Crossrail trains and that can just as readily take place at Ealing Broadway.

 

Really? Surely the point, providing grade separation between Crossrail services heading west and, eventually, north, is obvious. With two central reversing platforms/sidings required in the meantime, allowing these to extend north under the Up Relief is entirely logical.

 

 

It doesn't do anything to sort Down Crossrail trains crossing over the Up Relief - which is likely in any event to be the most frequent conflict and the biggest pinch on capacity - while at the same time as all the depot areas are going it would be simple to keep Crossrail on a northern pair of lines with a station which could be opened completely separately (suitably aligned) long before anything else needs to be built. 

 

Why would that be the most frequent conflict?

 

Surely everything but the 2tph residual service on the reliefs east of Old Oak Common will be operated by Crossrail - subsuming them into Crossrail too, as anticipated by Network Rail in their Western Route Study, will be the easiest solution.

 

If you haven't already it's worth reading the Route Study to see how NR are proposing to increase capacity into Paddington.

[The Stationmaster]

I can't imagine the flyover will prove as big an obstacle to pathing if not bigger than fitting such trains between all the electric Crossrail and GWR services - it won't be easy but that's for running such trains into any London termini.

  

 

Really? Surely the point, providing grade separation between Crossrail services heading west and, eventually, north, is obvious. With two central reversing platforms/sidings required in the meantime, allowing these to extend north under the Up Relief is entirely logical.

 

 

 

Why would that be the most frequent conflict?

 

Surely everything but the 2tph residual service on the reliefs east of Old Oak Common will be operated by Crossrail - subsuming them into Crossrail too, as anticipated by Network Rail in their Western Route Study, will be the easiest solution.

 

If you haven't already it's worth reading the Route Study to see how NR are proposing to increase capacity into Paddington.

 

I think you'll find the answer in that document - the Mains will not meet the capacity required so some (slower) trains will have no alternative but to use the Reliefs.  The line capacity which will be taken by Crossrail is at the heart of the problem and the logical answer is to separate that, and certainly separate what it does or doesn't need to turn northwards at Old Oak (plus of course trains which terminate there/at paddington will have to turn round there anyway.  There is a fundamental difference between Crossrail's inner suburban aspiration (basically an all stations service) and outer suburban trains which are too sow for the Mains but need only very limited stops - stopping trains steal capacity from semi-fasts (or vice versa of course)

 

The French, I'm pleased to say have usually recognised this sort of problem when they have introduced RERs and LGVs by increasing the available infrastructure rather than crowding things onto existing infrastructure with a consequent degrading of actual performance.  The problem with doing that in Britain is that it costs money and the Govt etc don't like spending money

[roundhouse]

I think you'll find the answer in that document - the Mains will not meet the capacity required so some (slower) trains will have no alternative but to use the Reliefs.  The line capacity which will be taken by Crossrail is at the heart of the problem and the logical answer is to separate that, and certainly separate what it does or doesn't need to turn northwards at Old Oak (plus of course trains which terminate there/at paddington will have to turn round there anyway.  There is a fundamental difference between Crossrail's inner suburban aspiration (basically an all stations service) and outer suburban trains which are too sow for the Mains but need only very limited stops - stopping trains steal capacity from semi-fasts (or vice versa of course)

 

The French, I'm pleased to say have usually recognised this sort of problem when they have introduced RERs and LGVs by increasing the available infrastructure rather than crowding things onto existing infrastructure with a consequent degrading of actual performance.  The problem with doing that in Britain is that it costs money and the Govt etc don't like spending money

This is one of my big concerns with the current Thameslink project.

 

Just need one failed train or incident in the central core area and you can say goodbye ot the performance of the service for a good part of the day to numerous places in the South East

Edited August 15, 2016 by roundhouse

[The Stationmaster]

This is one of my big concerns with the current Thameslink project.

 

Just need one failed train or incident in the central core area and you can say goodbye ot the performance of the service for a good part of the day to numerous places in the South East

 

It is a problem with any sort of intensive operation which pushes lone capacity to its limits and there is (or certainly used to be) a UIC capacity formula which allowed potential reliability problems to be estimated in relation to the extent to which capacity was used.

 

The traditional British answer has long been to ignore the UIC fiches and simply shove as much as possible into whatever line capacity has been created - the frequent consequences of that approach are there for some of us to see on an almost daily basis, unfortunately.

 

The important things about pushing capacity to the limits is also having the ability to quickly recover from any sort of minor incident but the things (mainly people) which allow that sort of resilience have become increasingly rare commodities on the British network.

[ess1uk]

i've been stood at Old Oak Lane today trying to work out how this would all work

 

Sorry, I'm referring to the lightly used connection between the GWML at Old Oak Common and the Chiltern Mainline via North Action and Greenford.
 

AFAIK there are no plans for a second pair of tracks, the plan always being for Crossrail trains to have a pair of central turnback sidings/platforms at Old Oak Common between the relief lines.

This diagram and visualisation shows what is planned.

looks like the substation might have to move?

[The Stationmaster]

i've been stood at Old Oak Lane today trying to work out how this would all work

 

looks like the substation might have to move?

 

I don't know if the substation is still used - but if it is then it will probably have to move as I read those plans.  And it looks also as if the bridge over the Central Line might have to be altered/extended.

[ess1uk]

the substation is still in use but controlled from Rugby ECR.

would make more sense to control it from Didcot ROC ?

 

I don't know if the substation is still used - but if it is then it will probably have to move as I read those plans.  And it looks also as if the bridge over the Central Line might have to be altered/extended.

[phil-b259]

the substation is still in use but controlled from Rugby ECR.

would make more sense to control it from Didcot ROC ?

 

In time, it might be.

 

I imagine the reason the old Oak substation is controlled from Rugby is the same as why the OHL from St Pancras to Bedford is controlled by York. (i.e. BR didn't go to the trouble of setting up new ECRs for smallish schemes)

 

When the GWML has wires all the way from Paddington to Swansea then having the controlling ECR actually on the route would be a sensible move (and I doubt Rugby can accommodate it all anyway)

[Christopher125]

I think you'll find the answer in that document - the Mains will not meet the capacity required so some (slower) trains will have no alternative but to use the Reliefs.

 

 

IMO it suggests the exact opposite - they anticipate Crossrail taking over the 2tph 'residual' service and 'all remaining Relief Line capacity east of Old Oak Common' with the potential for more capacity on the Mains.

 

That extra capacity could be used by semi-fast services running fast to Langley where a grade separated junction would allow them to join the Reliefs; the other option given is a pair of dynamic loops on the Reliefs, with the semi-fasts operated by Crossrail.

[Zomboid]

In time, it might be.

 

I imagine the reason the old Oak substation is controlled from Rugby is the same as why the OHL from St Pancras to Bedford is controlled by York. (i.e. BR didn't go to the trouble of setting up new ECRs for smallish schemes)

 

When the GWML has wires all the way from Paddington to Swansea then having the controlling ECR actually on the route would be a sensible move (and I doubt Rugby can accommodate it all anyway)

Slough ECR was very short lived, but did exist... There's a new feeder station being built nearer Paddington, which will probably replaced Old Oak, as the original HEX scheme didn't allow for the autotransformer scheme.

[QuoitsPlayer]

^{Hi - apologies in advance if this question is stupid.}

 

^{Will the Crossrail units be getting yellow warning panels on the front?}

[The Stationmaster]

 

 

IMO it suggests the exact opposite - they anticipate Crossrail taking over the 2tph 'residual' service and 'all remaining Relief Line capacity east of Old Oak Common' with the potential for more capacity on the Mains.

 

That extra capacity could be used by semi-fast services running fast to Langley where a grade separated junction would allow them to join the Reliefs; the other option given is a pair of dynamic loops on the Reliefs, with the semi-fasts operated by Crossrail.

 

Which sort of ignores the fact that already in the peaks there are already 20tph running on the Mains and have been for some years.  If Class the 800s run at higher than 125 mph then the reduction in speed differential secured by the 387s will again open up - thus reducing capacity (or extending journey time between London and reading) and in any case any acceleration above or extension eastwards of the existing 125 mph linespeed will reduce capacity because the HEX units would no no longer match running times from Paddington to Airport Jcn (in fact that could well happen anyway depending on the acceleration rate of the Class 800 on 25kv?).

 

We (and I'm talking what local commuter groups) have already said they rcertainly don't want toilet-less, uncomfortable, Crossrail sets running Thames Valley services - ideally these inner-suburban trains should have been kept in an inner suburban area and not used on longer journeys.  If that happens as you suggest it sounds like a good time to buy shares in care dealerships in the Thames Valley and help clog up the M4 and M40 even more  People already come across from the Wokingham/Bracknell area to the GWML for faster services into London so I doubt they'd be too pleased with having to spend 40 minutes on what is basically an UndergrounD with a fancy nose end.  And don't forget - as I've already said there are potentially 6 running lines available from Old Oak West inwards and there are already more than 6 from Old Oak Common East.  

 

And don't forget that further out Crossrail is very much the new arrival and whether or not they have yet sussed it they are inevitably going to have to be the last on the graph in order to produce a workable train service on the Relief Lines and to allow proper use of line capacity when they will be easily outrun by freights.  (and oh yes, I can tell you from experience that it makes a big difference according to which trains go on the graph first - a very experienced timer had several goes at trying to make CTRL work and couldn't until I told him which trains to put on the graph first - he did what I suggested and it worked like a dream; there's a lot more to this sort of thing than computer train timing programs are ever likely to solve, as the London Bridge debacle showed)

[Zomboid]

It'll be interesting to see what the impact on the Windsor side services is once Crossrail reduces the quality on offer from Maidenhead etc. Will the good folk of Bracknell head for the 458/5s into Waterloo (the line is being upgraded to allow 10 car trains on the Reading route), or would they rather take the glorified tube? Guess it'll depend on their actual start and finish points, but for me the 458s are at least intended for use on that kind of journey.