Suggestions on how to boost MML capacity once the current improvements are completed

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59CosG95

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Will there be any spare capacity for new services once all the four-tracking, wires and platforms are done? Beyond the second Corby... seems like a pretty roomy railway, but appreciate the real issues are south of Bedford.
The real issues are indeed south of Bedford; the MML gets more congested the closer you get to London. Granted, most faster Thameslink services switch to the Slows after St. Albans, but the infrastructure constraints remain, particularly when it runs parallel to the M1 near Hendon, and through Elstree Tunnels.
EWR should certainly help with the freight side of things.
 

59CosG95

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Can you expand on that? What will new freight routes be to avoid the southern MML?
I'm not entirely sure to be honest, but some flows (such as Tunstead - Theale or Oxwellmains - Thurrock; both of which use the southern MML) could be rerouted via the EWR routes heading west & east from Bedford respectively.
Certainly the Tunstead - Theale trains could run Bedford - Bletchley - Bicester - Oxford - Reading Triangle - Theale, but all the freight on EWR depends on the timetable of proposed services and infrasturcture works on the route there (Fenny Stratford & Bedford St Johns are both single lead junctions which hamper capacity). Capacity south of Bedford for additional services also depends on traffic sustainability of the aggregate traffic using the route.
 

cle

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If TL ticketed passengers were able to use the future Corby trains too (2tph of 12 cars to Luton AP/Town and Bedford) - might a TL service or two be able to be truncated or diverted elsewhere to open up a longer distance frequency?
 

edwin_m

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I'm not entirely sure to be honest, but some flows (such as Tunstead - Theale or Oxwellmains - Thurrock; both of which use the southern MML) could be rerouted via the EWR routes heading west & east from Bedford respectively.
Certainly the Tunstead - Theale trains could run Bedford - Bletchley - Bicester - Oxford - Reading Triangle - Theale, but all the freight on EWR depends on the timetable of proposed services and infrasturcture works on the route there (Fenny Stratford & Bedford St Johns are both single lead junctions which hamper capacity). Capacity south of Bedford for additional services also depends on traffic sustainability of the aggregate traffic using the route.
West would be possible and if I recall correctly there is an allowance for freight paths in the proposed timetable. But I don't think any of the options allows freight to run between the east and the north without a run-round, which would be time-consuming even if the necessary facilities were provided.
 

Bald Rick

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If TL ticketed passengers were able to use the future Corby trains too (2tph of 12 cars to Luton AP/Town and Bedford) - might a TL service or two be able to be truncated or diverted elsewhere to open up a longer distance frequency?

Passengers from Luton / Bedford will be able to use the Corby services, in the same way that they can use the EMR services today (Acknowledging the current peak timetable doesn’t make it easy).

But it’s unlikely that this will divert enough passengers to enable TL services to be reduced. To put it into context, on the ‘fast’ services, over half of the passengers are for St Albans and Harpenden alone, with the remaining ‘less than half’ for all the remaining stations north to Bedford. Of which Luton and Bedford are but two.
 

cle

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Yep I figured. I did specify TL-ticketed passengers. I know anyone can buy an 'IC' ticket. And I mentioned Luton Airport Parkway too, which will help fill these trains outside of the peaks when St Albans and Harpenden demand plummets. Trying to be creative in terms of pathing and where anything might exist to open up more.

Perhaps an off-peak easement and reallocation of fasts would work - or conversely, off peak extensions of TL to Corby and trim the odd service from that pattern.
 

hwl

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Yep I figured. I did specify TL-ticketed passengers. I know anyone can buy an 'IC' ticket. And I mentioned Luton Airport Parkway too, which will help fill these trains outside of the peaks when St Albans and Harpenden demand plummets. Trying to be creative in terms of pathing and where anything might exist to open up more.

Perhaps an off-peak easement and reallocation of fasts would work - or conversely, off peak extensions of TL to Corby and trim the odd service from that pattern.

Not enough stock for Corby. (not enough stock as is)

Off peak some of the attractiveness is not having to change if you are going through the core - you have to think about it from the south of the Thames users or future crossrail interchangers at Farringdon not just local MML.
 

Bald Rick

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Yep I figured. I did specify TL-ticketed passengers. I know anyone can buy an 'IC' ticket. And I mentioned Luton Airport Parkway too, which will help fill these trains outside of the peaks when St Albans and Harpenden demand plummets. Trying to be creative in terms of pathing and where anything might exist to open up more.

Perhaps an off-peak easement and reallocation of fasts would work - or conversely, off peak extensions of TL to Corby and trim the odd service from that pattern.

Are there TL or EMR only tickets Bedford / Luton to London? I don’t think there are.

The airport will certainly help to fill the Corbys, indeed I suspect that will be the majority of the custom off peak, particularly when the DART transit opens to the airport in around 24 months time.

I can tell you that St Albans demand (at least) doesn’t plummet in the off peak proportionately to Luton and Bedford. If anything it’s the opposite. Regularly there will be 100+ boarding trains at St Albans off peak, and this is with a train every 15 minutes. At weekends it’s much more - not unusual to see standing on 12 car services into London on Saturday and Sunday before lunchtime.
 

DPWH

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It would be amusing if it were true, but it's far more likely to be due to geography. Fairly flat open terrain, so easy to build runways. Not terribly far from supplies of armaments, fuel etc. As close to Germany as it's possible to get.

The real issues are indeed south of Bedford; the MML gets more congested the closer you get to London. Granted, most faster Thameslink services switch to the Slows after St. Albans, but the infrastructure constraints remain, particularly when it runs parallel to the M1 near Hendon, and through Elstree Tunnels.
EWR should certainly help with the freight side of things.

AFAIK, trains switching from the fasts to the slows and vice-versa is in fact part of the problem. Because it is fast-fast-slow-slow, rather than slow-fast-fast-slow or fast-slow-slow-fast anything crossing over has to cross over a line coming the other way. That could be helped by a strategically-placed flyover.
 

edwin_m

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AFAIK, trains switching from the fasts to the slows and vice-versa is in fact part of the problem. Because it is fast-fast-slow-slow, rather than slow-fast-fast-slow or fast-slow-slow-fast anything crossing over has to cross over a line coming the other way. That could be helped by a strategically-placed flyover.
We've discussed this before. It would most likely be in the rural area between St Albans and Harpenden, which is about where the faster Thameslinks need to cross onto the Slows, but far from cheap or easy.
 

Bald Rick

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We've discussed this before. It would most likely be in the rural area between St Albans and Harpenden, which is about where the faster Thameslinks need to cross onto the Slows, but far from cheap or easy.

And not rural for much longer. A lot of development planned adjacent to the railway.
 

paul1609

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As an observation the Thameslink Main Line appears to achieve higher passenger capacity on the 2 track section south of Balcombe than it does on the 4 track Bedford branch. It appears to be the case that the Regional DEMU service is eating up loads of badly needed commuter capacity.
Id suggest the following improvements would give the same benefits as unaffordable infrastructure projects.
1) Reduce the line limit south of kettering to 100 mph.
2) Transfer the Corby Service to Thameslink
3) Off peak introduce portion working with 6 car IETs splitting at Leicester for Nottingham and Sheffield.
4) Introducing extra stops on the regional services so they have a standard stopping pattern of West Hampstead, St Albans, Luton Airport and Bedford.
 

Bald Rick

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As an observation the Thameslink Main Line appears to achieve higher passenger capacity on the 2 track section south of Balcombe than it does on the 4 track Bedford branch. It appears to be the case that the Regional DEMU service is eating up loads of badly needed commuter capacity.
Id suggest the following improvements would give the same benefits as unaffordable infrastructure projects.
1) Reduce the line limit south of kettering to 100 mph.
2) Transfer the Corby Service to Thameslink
3) Off peak introduce portion working with 6 car IETs splitting at Leicester for Nottingham and Sheffield.
4) Introducing extra stops on the regional services so they have a standard stopping pattern of West Hampstead, St Albans, Luton Airport and Bedford.

The Corby can’t be transferred to Thameslink - not enough 700 units, no extra paths through the core, and they are full already in the peak without the extra passengers.

Extra stops in the ‘beyond Leiceter’ EMR services would crucify journey items, causing significant revenue loss. Given the passenger numbers at St Albans, EMR wouldn’t want their trains to Sheffield full of punters travelling the first 19 miles. (There are, typically, more people boarding each of the peak 8tph ‘fast’ Thameslink services just at St Albans than are carried on each of the EMR services that have picked up passengers all the way from Sheffield / Nottingham).
 

edwin_m

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East Midlands already has slower London services than other cities - the time to Sheffield is about the same as Wigan or York which are much further north. The ECML and WCML also have four-track sections with extensive commuter services so should the fast trains be slowed down there too? Portion working would slow these services further and also halve the frequency between London and Leicester.

Assuming an appropriate interior refit of the 360s, the Corby trains should offer a better standard of comfort for Luton and Bedford passengers than Thameslink does, partly replicating what they have now on the EMR service but with much more capacity. But that also means they wouldn't be compatible with the Thameslink core (where there probably aren't southern destinations to absorb them anyway). So they would still terminate at St Pancras and run pretty much the same service even if badged as Thameslink.
 

Aictos

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As an observation the Thameslink Main Line appears to achieve higher passenger capacity on the 2 track section south of Balcombe than it does on the 4 track Bedford branch. It appears to be the case that the Regional DEMU service is eating up loads of badly needed commuter capacity.

Could this not be because the service in the Southern region operates a far more intensive timetable then anywhere else?

Id suggest the following improvements would give the same benefits as unaffordable infrastructure projects.
1) Reduce the line limit south of kettering to 100 mph.

Yes, great idea as it would make services north of Bedford even more slower then they need to be.

What NR ought to do is raise the speed limits in more places to provide more 110mph/125mph running where possible.

2) Transfer the Corby Service to Thameslink

That's going to go down well with passengers north of Bedford who pay IC fares and who expect IC trains.

3) Off peak introduce portion working with 6 car IETs splitting at Leicester for Nottingham and Sheffield.
.

This might not be a bad idea but I'm sure it's already been thought of for the Dec 2020 timetable.

4) Introducing extra stops on the regional services so they have a standard stopping pattern of West Hampstead, St Albans, Luton Airport and Bedford.

God NO, that would wreck the MML IC timetable in mins! See my answer to point 1 why it's a awful idea!
 

Roast Veg

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Even calling EMR regional is (and there has been much discussion on the matter) disingenuous as to the actual purpose of the services. EMR themselves describe it as "Intercity", as opposed to their "Regional" and soon-to-be "Electric" services. Line speed has been incrementally improving on these lines with Market Harborough and Leicester works increasing the speed through the stations. Services to the East Midlands area could and should be improved in journey time - they are far slower at present than they should be.
 

Aictos

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Even calling EMR regional is (and there has been much discussion on the matter) disingenuous as to the actual purpose of the services. EMR themselves describe it as "Intercity", as opposed to their "Regional" and soon-to-be "Electric" services. Line speed has been incrementally improving on these lines with Market Harborough and Leicester works increasing the speed through the stations. Services to the East Midlands area could and should be improved in journey time - they are far slower at present than they should be.

I agree, there is a lot more that can be done with line speed upgrades and Leicester with its approaches being another.
 

Bald Rick

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I agree, there is a lot more that can be done with line speed upgrades and Leicester with its approaches being another.

Where is there more that can be done with linespeed? The project completed a few years ago really wrung it out.
 

Aictos

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Where is there more that can be done with linespeed? The project completed a few years ago really wrung it out.

Well does having platforms impact line speeds?

I ask because on my travels, I’ve seen a 90mph for the Up Fast just south of Platform 4 at Luton - could this not be raised to 100mph or 110mph?

That’s only be example, the only other methods of raising line speeds is remodelling Leicester and it’s approaches/Bedford.
 

Raul_Duke

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Being 3 aspect signalling from Barrow on Soar to Sharnbrook doesn’t really help capacity that much.

And you can whizz about at 125 all you like, if you don’t get checked down at Chiltern Green then you’re probably going to get brought to a stand for a TL to cross over at Radlett whether you’re on time or not.
 

The Planner

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Being 3 aspect signalling from Barrow on Soar to Sharnbrook doesn’t really help capacity that much.

And you can whizz about at 125 all you like, if you don’t get checked down at Chiltern Green then you’re probably going to get brought to a stand for a TL to cross over at Radlett whether you’re on time or not.
4 aspect doesn't necessarily make it better, if the green to green spacing increases then your capacity goes down.
 

edwin_m

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4 aspect doesn't necessarily make it better, if the green to green spacing increases then your capacity goes down.
I seem to remember that the 3-aspects in the Leicester scheme were positioned so that they could be replaced by 4-aspects in the same positions plus an extra one near the middle of each gap. That may of course have been invalidated by standards changes or line speed increases in the last 30-odd years. But if it's still possible it would reduce the green to green spacing and hence the headway. It would also improve performance during disruption because currently a driver seeing a yellow has to brake assuming the next signal is red, and if that signal clears in the meantime the driver can't accelerate until it comes into view - by which time they will be down to a few tens of mph. With four-aspect the driver starts braking in the same place (at a double yellow), but can stop braking at the intervening signal if it is double yellow or green.

However I'd question how much of a constraint the three-aspect signaling actually is. The MML fast and slow services are only 3min or so apart at St Pancras but because of different stopping patterns they are more widely spaced north of Sharnbrook. The Leicesters are close to the Corbies in the Kettering area, but I assume if going to four aspect signaling could have resolved that with the previous track layout, then they would have done so instead of adding a fourth track! ERTMS would reduce the performance issue even with the existing blocks, because the train would get a new movement authority as soon as a one in front had cleared the block.
 

DPWH

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The whole thing needs a high speed line from London-Leicester-Nottingham to join up with the eastern branch of HS2.

I know that's just a crayon line at this stage, but if you take several cities, divide their population size by distance to London, and plot that metric against time to London, I reckon Leicester would come out top as the one needing its links improved. Far more than Cambridge which is usually suggested as an alternative.

That would then free up paths on Thameslink and south of Leicester for medium-fast intercity trains.

(I know this isn't the speculative ideas forum, but you did ask...)
 

Raul_Duke

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One of the regular problems you have with 3 aspect is approaching Leicester on the down.

If you’ve lost your path over the junction at Wigston for whatever reason (Probably Thameslink related) then you will get a single yellow at Kilby Bridge and the red is at the end of a really massive section but helpfully hidden behind a bridge and round a sharp corner.

So instead of braking from 110 to 80 for Wigston curve you’re braking for a red (which will more than likely be green when you get to it)

By the time you see the signal you’ll probably be down to about 20mph (if you’re sensible....) and in an HST you’ll be lucky to get back upto 50 into Leicester.

Which means you’re late at Sheet stores so you get held, lose your path into derby for the Notts XC and late at Dore so get held for the TPE/Notherns and so on and so on.
 

Dr Hoo

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One of the regular problems you have with 3 aspect is approaching Leicester on the down.

If you’ve lost your path over the junction at Wigston for whatever reason (Probably Thameslink related) then you will get a single yellow at Kilby Bridge and the red is at the end of a really massive section but helpfully hidden behind a bridge and round a sharp corner.

So instead of braking from 110 to 80 for Wigston curve you’re braking for a red (which will more than likely be green when you get to it)

By the time you see the signal you’ll probably be down to about 20mph (if you’re sensible....) and in an HST you’ll be lucky to get back upto 50 into Leicester.

Which means you’re late at Sheet stores so you get held, lose your path into derby for the Notts XC and late at Dore so get held for the TPE/Notherns and so on and so on.
As a regular user of the Sheffield service, with innumerable missed connections to the hourly Hope Valley service under my belt, this is indeed exactly how it is with the current three-aspect signalling.
 

Bald Rick

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One of the regular problems you have with 3 aspect is approaching Leicester on the down.

If you’ve lost your path over the junction at Wigston for whatever reason (Probably Thameslink related) then you will get a single yellow at Kilby Bridge and the red is at the end of a really massive section but helpfully hidden behind a bridge and round a sharp corner.

So instead of braking from 110 to 80 for Wigston curve you’re braking for a red (which will more than likely be green when you get to it)

By the time you see the signal you’ll probably be down to about 20mph (if you’re sensible....) and in an HST you’ll be lucky to get back upto 50 into Leicester.

Which means you’re late at Sheet stores so you get held, lose your path into derby for the Notts XC and late at Dore so get held for the TPE/Notherns and so on and so on.

Sounds like a good candidate for a 3 state banner at LR259. Can you suggest it to your manager, and make sure he gets it through to NR.
 

Senex

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One of the regular problems you have with 3 aspect is approaching Leicester on the down.

If you’ve lost your path over the junction at Wigston for whatever reason (Probably Thameslink related) then you will get a single yellow at Kilby Bridge and the red is at the end of a really massive section but helpfully hidden behind a bridge and round a sharp corner.

So instead of braking from 110 to 80 for Wigston curve you’re braking for a red (which will more than likely be green when you get to it)

By the time you see the signal you’ll probably be down to about 20mph (if you’re sensible....) and in an HST you’ll be lucky to get back upto 50 into Leicester.

Which means you’re late at Sheet stores so you get held, lose your path into derby for the Notts XC and late at Dore so get held for the TPE/Notherns and so on and so on.

Even worse than that, if my regular experience over a couple of decades after the commissioning of the MAS. There is a signal between Kilby Bridge and Wigston North, at Wigston South. But it's not at full braking distance from the north junction signal and so a down train gets its yellow at Kilby Bridge, which is indeed a massive distance away. What always seemed to happen was that drivers would brake hard as soon as they saw the yellow, pass the signal already slowing markedly, and drop right down to 30 to 40 mph, sustaining this right up to seeing the south junction signal all being well clear. For the trains I was using this meant on many occasions that an "on time" run was in fact late into Leicester as a result of the time lost by these signals. (Another cause of delay into Leicester in those early days was the fact that the Leicester South signal would only clear from red when a train passed the AWS magnet unless the platform signal was already shewing yellow or red.)

In response to edwin_m above, I too heard that the signal-spacing was such that the sections could simply have additional signals put in the middle if four aspects were wanted, the resulting sections duly being about ¾-mile in length. That scheme had a complicated gestation. Original planning was for four aspects. This then became three, then two, then went back to three again as carried out. The full reversible signalling was added in very late in the day (but before the Market Harborough modernisation was ditched).
 

Bald Rick

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In response to edwin_m above, I too heard that the signal-spacing was such that the sections could simply have additional signals put in the middle if four aspects were wanted, the resulting sections duly being about ¾-mile in length. That scheme had a complicated gestation. Original planning was for four aspects. This then became three, then two, then went back to three again as carried out. The full reversible signalling was added in very late in the day (but before the Market Harborough modernisation was ditched).

Yes, Leicester resignalling was pared down significantly; you can tell by looking at the signal numbers on the open train times maps. There some big gaps in the sequences!

This is not to criticise the BR planners of the 80s - back then the MML had, at most 3 trains an hour between Bedford and Leicester, so a full 4 aspect scheme would have been rather extravagant to put it mildly (in the context of BR being under very strict financial limits). What the planners did sneak under the radar was to keep in the electrification compatibility, which has helped the MML electrification team no end as the signalling was already ‘immune’ and the gantries to the right size.
 
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