MML electrification aspirations and potential for journey time improvements

[WAO]

Moderator note: split from https://www.railforums.co.uk/threads/mml-electrification-progress-updates.110445

There's also the Syston - Trent wiring scheme in planning, based on the idea that the long open country stretches are cheaper and simpler, with bi-modes doing the difficult bits on diesel (for the moment).

There are two influential bodies chasing government over this; The Midlands Engine Hub and EM Chamber.The Midlands Engine has gained a £600M budget for "necessary electrification".

It has improvement of services from B'ham in mind of course but also the MML. In particular a Leicester - London time below an hour has been mentioned as has a direct connection from Leicester to Leeds (which Nottingham has and uses well).

The loss of HS2 Eastern Leg probably favours more investment in the MML in my view, as well as the extension of some EMR services to Leeds.

Anyone for the Thames-Clyde Express?

WAO

 

[baz962]

There's also the Syston - Trent wiring scheme in planning, based on the idea that the long open country stretches are cheaper and simpler, with bi-modes doing the difficult bits on diesel (for the moment).

There are two influential bodies chasing government over this; The Midlands Engine Hub and EM Chamber.The Midlands Engine has gained a £600M budget for "necessary electrification". It has improvement of services from B'ham in mind of course but also the MML. In particular a Leicester - London time below an hour has been mentioned as has a direct connection from Leicester to Leeds (which Nottingham has and uses well). The loss of HS2 Eastern Leg probably favours more investment in the MML in my view, as well as the extension of some EMR services to Leeds.

Anyone for the Thames-Clyde Express?

WAO

What do you mean by London to Leicester in under an hour. Electrification won't change anything. It can already be done in under an hour just in a 222 . Although the acceleration should be better in ac in an 810 it is apparently worse than a 222 in diesel mode. And a lot of the time you don't make it under an hour because you are behind a Thameslink or a 360 or Wigston is double blocked.

 

[edwin_m]

What do you mean by London to Leicester in under an hour. Electrification won't change anything. It can already be done in under an hour just in a 222 . Although the acceleration should be better in ac in an 810 it is apparently worse than a 222 in diesel mode. And a lot of the time you don't make it under an hour because you are behind a Thameslink or a 360 or Wigston is double blocked.

It follows from this that electrifying the parts of the MML where electric performance will permit higher speeds or better accelerations will reduce journey times, and might do enough to get the time reliably below 1hr.

South of Bedford, there probably won't be much benefit south of Bedford where 222s can sustain 125mph for reasonable distances. But I think the 360s are still limited to 100mph here until the current works are complete, after which an increase to 110 will help them keep ahead of the 810s.

Further north where the speed profile jumps up and down much more, electric acceleration will make more difference. There may even be sections where the alignment allows higher speeds but nobody has bothered with them because the diesels would never attain them.

I'm not sure why Wigston is a particular problem - I know there is a repeated aspect due to signal spacing but it's only an issue if there's another train in front. And (assuming something like today's timetable) electric performance would improve the timings for the trains making the Kettering and MH stops more than it improves the non-stops, thus reducing the difference between them and making it less likely they will catch each other up.

 

[baz962]

It follows from this that electrifying the parts of the MML where electric performance will permit higher speeds or better accelerations will reduce journey times, and might do enough to get the time reliably below 1hr.

South of Bedford, there probably won't be much benefit south of Bedford where 222s can sustain 125mph for reasonable distances. But I think the 360s are still limited to 100mph here until the current works are complete, after which an increase to 110 will help them keep ahead of the 810s.

Further north where the speed profile jumps up and down much more, electric acceleration will make more difference. There may even be sections where the alignment allows higher speeds but nobody has bothered with them because the diesels would never attain them.

I'm not sure why Wigston is a particular problem - I know there is a repeated aspect due to signal spacing but it's only an issue if there's another train in front. And (assuming something like today's timetable) electric performance would improve the timings for the trains making the Kettering and MH stops more than it improves the non-stops, thus reducing the difference between them and making it less likely they will catch each other up.

Of course if they can speed up the 360 then maybe , but will the timetable be changed once they can run faster. Still quite often have to wait for a Thameslink to go over at Harpenden , but maybe I guess if they can speed everything up. Just thought as well , raising and lowering the pan might eat into the time.

 

[WAO]

What do you mean by London to Leicester in under an hour.

I was only quoting the Midlands advocates of wiring!

An EMU should be able to accelerate and hold top speed better than a DMU, although the 22x's, with all those underfloor Diesels are very competent units, even beating 810's on Diesel. They can't however compete on running costs etc, which is why they are being replaced.

As you say this is all irrelevant if they're run behind stoppers!

WAO

 

[43074]

What do you mean by London to Leicester in under an hour. Electrification won't change anything. It can already be done in under an hour just in a 222 . Although the acceleration should be better in ac in an 810 it is apparently worse than a 222 in diesel mode. And a lot of the time you don't make it under an hour because you are behind a Thameslink or a 360 or Wigston is double blocked.

The fastest I've done London to Leicester on a 222 is 60 minutes and 30 seconds northbound and 61 minutes southbound. The Railway Performance Society fastest is 59 minutes 50 seconds northbound set in 2015, but southbound is still 61 minutes. I think Leicester to London in under an hour on a 222 would be pretty exceptional.

I'm sceptical that an 810 could improve on that, given the speed record is 58 minutes, and that was set by the APT with a stretch of 135mph between Bedford and Luton and tilting through Kettering/Wellingborough in 1975. I think this shows the speed profile on the MML is now at the point where a lot of work would be needed to get very marginal gains to journey times.

 

[baz962]

The fastest I've done London to Leicester on a 222 is 60 minutes and 30 seconds northbound and 61 minutes southbound. The Railway Performance Society fastest is 59 minutes 50 seconds northbound set in 2015, but southbound is still 61 minutes. I think Leicester to London in under an hour on a 222 would be pretty exceptional.

I'm sceptical that an 810 could improve on that, given the speed record is 58 minutes, and that was set by the APT with a stretch of 135mph between Bedford and Luton and tilting through Kettering/Wellingborough in 1975. I think this shows the speed profile on the MML is now at the point where a lot of work would be needed to get very marginal gains to journey times.

Yes I noticed I have never done under an hour south. I did 59.40 ish Northbound and that was with a 50 speed restriction just before Harborough a month or so ago.

 

[edwin_m]

Of course if they can speed up the 360 then maybe , but will the timetable be changed once they can run faster. Still quite often have to wait for a Thameslink to go over at Harpenden , but maybe I guess if they can speed everything up. Just thought as well , raising and lowering the pan might eat into the time.

Even if they don't change the timetable, the ability to run a bit faster means the 360 is less likely to be delayed and get in the way of the 810 behind.

 

[Bald Rick]

I’m obviously missing something here. The 810s are specified to have the same performance on diesel as the 222s, and have nearly 3MW / 4,000hp per 5 car unit to do so - slightly more than a 5 car 222, albeit the 810 is slightly longer.

I also understood that, as a result, their performance on electric would be broadly similar. AIUI a 5 car 80x has around 3MW electric power.

what am I missing?

 

[baz962]

I’m obviously missing something here. The 810s are specified to have the same performance on diesel as the 222s, and have nearly 3MW / 4,000hp per 5 car unit to do so - slightly more than a 5 car 222, albeit the 810 is slightly longer.

I also understood that, as a result, their performance on electric would be broadly similar. AIUI a 5 car 80x has around 3MW electric power.

what am I missing?

I was told by a fitter iirc that with the engine's and I think less in number than a 222 that with the extra weight of the pantograph equipment etc they will be quite a bit slower on diesel. But maybe they are wrong.

== Doublepost prevention - post automatically merged: 25 Jun 2023 ==

Even if they don't change the timetable, the ability to run a bit faster means the 360 is less likely to be delayed and get in the way of the 810 behind.

I was thinking though that if you don't change the timetable then a 360 running faster won't make any difference if it leaves Wellingborough at the same time as now. It's three aspect signalling from there, which from a driver point of view is a pain and it would still be going over Kettering south at 30mph.

 

[bluelagoon8951]

What do you mean by London to Leicester in under an hour. Electrification won't change anything. It can already be done in under an hour just in a 222 . Although the acceleration should be better in ac in an 810 it is apparently worse than a 222 in diesel mode. And a lot of the time you don't make it under an hour because you are behind a Thameslink or a 360 or Wigston is double blocked.

info out there suggests that 810s were specced specifically so diesel acceleration matched (or beat) 222s

 

[edwin_m]

I was told by a fitter iirc that with the engine's and I think less in number than a 222 that with the extra weight of the pantograph equipment etc they will be quite a bit slower on diesel. But maybe they are wrong.

== Doublepost prevention - post automatically merged: 25 Jun 2023 ==


I was thinking though that if you don't change the timetable then a 360 running faster won't make any difference if it leaves Wellingborough at the same time as now. It's three aspect signalling from there, which from a driver point of view is a pain and it would still be going over Kettering south at 30mph.

According to Wikipedia (yes I know) the 810 will only have four engines of 735kW each but the 222 has one per car of 559kW. So the 810 has slightly more power on board than a 5-car 222. No weights quoted but the 222 is pretty heavy so the 810 may be a bit lighter too.

I note this is a higher rated power than the earlier 80x units, and the shorter car length may mean it's squeezed into a bit less space. I hope there isn't an issue with overheating.

Better performance on the 360 wouldn't help if the 810 was catching it up southbound at Wellingborough but might mean it got to St Pancras a bit earlier so less likely to be caught up there. However, better performance on the 810 would allow it to pass Wellingborough later so less likely to catch the 360 there, and still get to St Pancras at the same time.

 

[43074]

However, better performance on the 810 would allow it to pass Wellingborough later so less likely to catch the 360 there, and still get to St Pancras at the same time.

Although on the non stop Leicester to London services they are on minimum headways in front of the 360 at Wellingborough and the Bedford to Brighton at Harpenden Jn so any time savings will need to be between Leicester and Wellingborough or Harpenden Jn and St Pancras if any time savings are to be found. Might save a minute at best.

 

[43066]

I was thinking though that if you don't change the timetable then a 360 running faster won't make any difference if it leaves Wellingborough at the same time as now. It's three aspect signalling from there, which from a driver point of view is a pain and it would still be going over Kettering south at 30mph.

It’s a pity they can’t find a way to path putting more of them across at Wellingborough North.

 

[baz962]

It’s a pity they can’t find a way to path putting more of them across at Wellingborough North.

I wish

 

[AM9]

According to Wikipedia (yes I know) the 810 will only have four engines of 735kW each but the 222 has one per car of 559kW. So the 810 has slightly more power on board than a 5-car 222. No weights quoted but the 222 is pretty heavy so the 810 may be a bit lighter too.

If it is pro rata, a five car 222 should weigh about 230-240t, against a 5-car 800 which is reported to be 243t, so the weights and power on diesel are very similar.

The class 360s have a stated power at the axles of 8 x 194kW giving a power to weight ratio of 9.23kW/tonne. A 5-car 810 will have a maximum of 2940 kW from the diesel engines which gives around 12.1kW/tonne. However when considering the acceleration performance of the two units, they may be much closer than expected:

1) the 360s are geared for a nominal 100mph maximum plus the (now) standard Desiro UK motor modification to permit running the motors faster to get a maximum service speed of 110mph, whereas the 810s are straight geared for 125 mph, meaning that the 360s may have better acceleration below (say) 80mph, where the acceleration of the 810s is spread across much of the 0-125mph range of the units. This the 360s will be much quicker away from standstill which might help maintain the headway of a following train more easily when the linespeed isn't a continuous 125mph.​

2) The maximum power on diesel of the 810s is 2940kW, but of course, under wires - when they are allowed to, the motors will have a combined short turn output at the axle far higher than their nominal power rating. The 360s would also have this advantage, so a diesel unit would still lag an DEMU of either type well into the higher speeds.​

I note this is a higher rated power than the earlier 80x units, and the shorter car length may mean it's squeezed into a bit less space. I hope there isn't an issue with overheating.

Better performance on the 360 wouldn't help if the 810 was catching it up southbound at Wellingborough but might mean it got to St Pancras a bit earlier so less likely to be caught up there. However, better performance on the 810 would allow it to pass Wellingborough later so less likely to catch the 360 there, and still get to St Pancras at the same time.

From my points above, I think that the better performance of the 360s as intermediate stoppers would help minimise their impact on the headways of following fast trains.

 

[edwin_m]

If it is pro rata, a five car 222 should weigh about 230-240t, against a 5-car 800 which is reported to be 243t, so the weights and power on diesel are very similar.

The class 360s have a stated power at the axles of 8 x 194kW giving a power to weight ratio of 9.23kW/tonne. A 5-car 810 will have a maximum of 2940 kW from the diesel engines which gives around 12.1kW/tonne. However when considering the acceleration performance of the two units, they may be much closer than expected:

1) the 360s are geared for a nominal 100mph maximum plus the (now) standard Desiro UK motor modification to permit running the motors faster to get a maximum service speed of 110mph, whereas the 810s are straight geared for 125 mph, meaning that the 360s may have better acceleration below (say) 80mph, where the acceleration of the 810s is spread across much of the 0-125mph range of the units. This the 360s will be much quicker away from standstill which might help maintain the headway of a following train more easily when the linespeed isn't a continuous 125mph.​

2) The maximum power on diesel of the 810s is 2940kW, but of course, under wires - when they are allowed to, the motors will have a combined short turn output at the axle far higher than their nominal power rating. The 360s would also have this advantage, so a diesel unit would still lag an DEMU of either type well into the higher speeds.​

From my points above, I think that the better performance of the 360s as intermediate stoppers would help minimise their impact on the headways of following fast trains.

I believe with AC motors the gearing isn't so critical, as the motors can provide higher torques at higher speeds than traditional DC motors. However, even if equal in other respects, the 360s will benefit more simply because they make the intermediate stops, so they will have more opportunity to gain time in acceleration.

 

[Bartsimho]

It’s a pity they can’t find a way to path putting more of them across at Wellingborough North.

The way I could think of finding the best time improvement would be having the old goods line at 100mph between Bedford and Corby as they could have the 360's avoid the fasts until then where they then just need to path in the Luton stops on the fasts

 

[Bald Rick]

The way I could think of finding the best time improvement would be having the old goods line at 100mph between Bedford and Corby as they could have the 360's avoid the fasts until then where they then just need to path in the Luton stops on the fasts

wouldn’t make much difference. In the down most trains off peak have little if any pathing time between Luton and Kettering. On the up, similar story, and in any event they’d just end up in the back of the Thameslink earlier.

 

[adamedwards]

Is there a location on the line where having a flyover might make a significant difference to capacity and speeds? Harpenden is clearly one such location but is there anywhere else where (money tree bearing unlimited fruit of course) a flyover could significantly improve things?

 

[edwin_m]

Is there a location on the line where having a flyover might make a significant difference to capacity and speeds? Harpenden is clearly one such location but is there anywhere else where (money tree bearing unlimited fruit of course) a flyover could significantly improve things?

Recalling also a forum discussion from some time back where we put forward an idea for a flyover between Harpenden and St Albans, taking advantage of the cutting and replacing the crossovers there for switching trains between the slows to the north and the fasts to the south.

I think the Radlett freight terminal includes a flyover if it ever goes ahead, which would to some extent duplicate this one.

 

[AM9]

Recalling also a forum discussion from some time back where we put forward an idea for a flyover between Harpenden and St Albans, taking advantage of the cutting and replacing the crossovers there for switching trains between the slows to the north and the fasts to the south.

I think the Radlett freight terminal includes a flyover if it ever goes ahead, which would to some extent duplicate this one.

The Radlett Strategic Rail Freight Interchange one wouldn't work as:
it is necessary for up and down Thameslink fasts to keep clear of the slows at St Albans where not only would the platforms be overcrowded in the peaks, - the recent addition of the second footbridge was needed to distruibute the crowds onto and off of the platforms more effectively.
the turning back of Metro services via the centre siding every 15 minutes consumes a large part of platform occupancy time.
That is why over recent years, the movements using the existing Radlett Junction F>S and S>F crossover ladders have largely been superceded by the use of the crossover ladder at Harpenden Junction.

 

[edwin_m]

The Radlett Strategic Rail Freight Interchange one wouldn't work as:
it is necessary for up and down Thameslink fasts to keep clear of the slows at St Albans where not only would the platforms be overcrowded in the peaks, - the recent addition of the second footbridge was needed to distruibute the crowds onto and off of the platforms more effectively.
the turning back of Metro services via the centre siding every 15 minutes consumes a large part of platform occupancy time.
That is why over recent years, the movements using the Radlett F>S and S>F crossover ladders have largely been superceded by the use of the crossover ladder at Harpenden Junction.

I agree we've had this discussion before and there's a lot of skepticism on this forum. Nevertheless, the project seems to be continuing.

I believe the St Albans turnback is still not track circuited so trains have to crawl in on a subsidiary aspect. Providing train detection and a main signalled route might be a relatively low-cost capacity improvement.

 

[AM9]

I agree we've had this discussion before and there's a lot of skepticism on this forum. Nevertheless, the project seems to be continuing.

I believe the St Albans turnback is still not track circuited so trains have to crawl in on a subsidiary aspect. Providing train detection and a main signalled route might be a relatively low-cost capacity improvement.

Actually I wasn't referring to the SRFI specifically, only the issue of using any crossover (flat or grade separated) to return down TL fast services to the slows south of St Albans. If all TL services used just P1 & 2, it would effectively make St Albans the second busiest two platform station in the home counties, (Chelmsford being the busiest), and unlike Chelmsford, where very few trains turn, using the siding every 15 minutes would throttle the whole timetable. The current full timetable would be permanently unachievable even if the reversing trains didn't need to keep below 5mph.

 

[edwin_m]

Actually I wasn't referring to the SRFI specifically, only the issue of using any crossover (flat or grade separated) to return down TL fast services to the slows south of St Albans. If all TL services used just P1 & 2, it would effectively make St Albans the second busiest two platform station in the home counties, (Chelmsford being the busiest), and unlike Chelmsford, where very few trains turn, using the siding every 15 minutes would throttle the whole timetable. The current full timetable would be permanently unachievable even if the reversing trains didn't need to keep below 5mph.

You clearly have more background on this than I do, and the conclusion seems to be that a "right handed" flyover south of St Albans as proposed for SFRI wouldn't be much use for Thameslink (though I'd argue if things are that tight already, then the turnback changes should be done anyway).

 

[Bald Rick]

Is there a location on the line where having a flyover might make a significant difference to capacity and speeds? Harpenden is clearly one such location but is there anywhere else where (money tree bearing unlimited fruit of course) a flyover could significantly improve things?

A flyover at Harpenden will do nothing for speeds, indeed it would be likely to slow down the Thameslink services.

Also having one at Harpenden, or anywhere else to get Thameslink trains from slow to fast southbound, vv northbound, is no use without the opposite flyover somewhere around West Hampstead.

And even then, i can’t see how it releases any usuable capacity.


The best place for a flyover that would improve speed and capacity would be from Kilby Bridge to Humberstone Road. Rather expensive, but would have some desirable side effects.

I think the Radlett freight terminal includes a flyover if it ever goes ahead, which would to some extent duplicate this one.

The flyover there is actually a dive under, and is purely for access to the terminal. The cost (and gradient!) of that is one of the reasons I don’t believe the terminal will ever see a train…

I believe the St Albans turnback is still not track circuited so trains have to crawl in on a subsidiary aspect. Providing train detection and a main signalled route might be a relatively low-cost capacity improvement.

It is track circuited now, it was done earlier this year. They have to crawl in because of the 5mph speed restriction into all Carriage Sidings (and yards) in the East Midlands route as per the General Instructions in the Sectional Appendix. Occasionally a driver forgets of course (I saw one last week), goes in at 15 and then drops Anchor when he/she looks up and sees the blocks approaching rapidly.

Many years ago we did look at using ATO / Autoreverse here, until someone realised that ETCS doesn’t have Autorverse functionality

 

[jagardner1984]

Silly question perhaps. But there are normally very few people leaving the arriving metro services at St Albans (the main flow from London being on the fasts).

Could it help to crossover south of the station “wrong line” arriving into platform 1 to terminate, then essentially the siding is not needed to turn it ? Obviously some bi-directional signalling needed.

Thus leaving Platform 2 free for the following arriving fast, which in turn gets out of the way of the EMR services sooner.

Historically, prior to the St Albans terminators, there was far more use of Platform 2 for Northbound Luton / Bedford services.

 

[Bald Rick]

Silly question perhaps. But there are normally very few people leaving the arriving metro services at St Albans (the main flow from London being on the fasts).

No such thing as a silly question, when it’s asked nicely! I have looked at this (very cursorily) as the former MD of FCC asked exactly the same question - albeit because she’d been told to and didn’t really understand what she was asking.

The answer is - it doesn’t help - for two reasons.

Firstly, to get the necessary Down Slow to Up Slow crossover in place somewhere that doesn’t restrict the linespeed means placing it at least half a mile from the station (and be 20mph max) and possibly further still (Where it could be higher speed). Either way, a train using that to turn back would occupy the up slow for a minimum of 12 minutes.

Secondly, whilst that train is occupying the up slow for 12 minutes, nothing else can use it. In the standard off peak hour there are 6 scheduled passenger trains plus two freights. And at peak times up to 10 trains an hour (0730 - 0830). In times of disruption, 12 is not unusual. That would not be possible to timetable at all, let alone with any margin for reliability.

(What I’m leading the witness to is that it would reduce capacity, not improve it).

 

[jagardner1984]

This is really fascinating @Bald Rick - thanks for the insight.

So the only other possibility would be a realignment at SAC to have a bay platform to terminate in between the Up slow and the Down slow ? Ie effectively put the turn back into the station ?

Which has some rather large geographical obstacles !

 

[AM9]

This is really fascinating @Bald Rick - thanks for the insight.

So the only other possibility would be a realignment at SAC to have a bay platform to terminate in between the Up slow and the Down slow ? Ie effectively put the turn back into the station ?

Which has some rather large geographical obstacles !

Well it could be tunneled underneath the station, - that would need one hell of a business case! A surface build including the inevitable land acquisition as you suggest would probably be more expensive than that.