Which routes in the UK make sense to increase linespeeds to 200 km/h (125 mph)

[SouthEastBuses]

Again, a thread where @zwk500 and @Bald Rick might be of most interest seeing that you guys appear to be experts on these sort of things!

Anyway let's begin. Just like the electrification thread I started a few weeks ago, I thought I would create this thread to talk about which railway lines in the UK would make the most sense to be upgraded for faster service.

For me, one line I can think of is Exeter to Reading via Newbury plus to Bristol then Birmingham. Whilst it might not make a big difference in journey times seeing the 800/802/220/221s go at 160-180 km/h (100-110 mph), one possible benefit of faster speed is to be able to make better use of the paths.

I also wonder if Didcot to Oxford & Coventry (once Nuneham Viaduct issues are all sorted) could be another line to be upgraded to 200 km/h (125 mph) running

 

[zwk500]

Again, expert is a tad far for me!

The routes where Linespeed matters are those involving London or other major population centres. But from 100 to 125 is about 8 seconds per mile difference. So e.g. London-Norwich raising from 110 to 125 probably doesn't make sense unless you were 4-tracking the route through to Ipswich.

For me, one line I can think of is Exeter to Reading via Newbury plus to Bristol then Birmingham. Whilst it might not make a big difference in journey times seeing the 800/802/220/221s go at 160-180 km/h (100-110 mph), one possible benefit of faster speed is to be able to make better use of the paths.

Going faster only makes better use of the paths if everything is going faster, but the B&H has Newbury locals and freight on it as well. There's also the issue of the line's geometry being quite problematic.

I also wonder if Didcot to Oxford & Coventry (once Nuneham Viaduct issues are all sorted) could be another line to be upgraded to 200 km/h (125 mph) running

Again, this is only worth it if you pay lots of money to provide additional capacity for the slow trains to get out of the way. Banbury-Fenny Compton 4-tracking would not be out of the question as to the scale of intervention you'd need to realise any benefit of faster running. But also see point 1 - 8secs/mile is only worth it if you get a good number of miles at that speed. Leamington Spa to Didcot isn't that far.

Birmingham-Bristol, Castle Cary-Exeter are probably the most likely candidates.

 

[SouthEastBuses]

Thanks for replying @zwk500 . Much appreciated and I'm certainly learning a lot!

Birmingham-Bristol, Castle Cary-Exeter are probably the most likely candidates.

Now that I think about, I'd also say between Manchester-Liverpool via Chat Moss, Leeds to York (if it's not already 200 / 125) might also be good candidates as well! The former in particular does have a lot of fast accelerating local EMU (Electric Multiple Unit) services which I believe do run at fairly high speeds (160 km/h?).

Further to that, I would also say Wolverhampton-Shrewsbury & Crewe-Chester (and maybe up to Llandudno Junction). Certainly if they were ever electrified, tilting Pendolinos could make the best use of the fast speeds (although whether the lines in question have as much as curves as the WCML to justify tilting I am not sure)

 

[Intercity110]

the west coast main-line?

 

[Ken H]

You need stretches where continuous 100mph and faster running is possible over large distances. Which is why Newcastle-London is made for 125. So concentrating on removing any bits where 100mph isnt possible on that route would be the best bet.

Far far better looking to increase line speeds on slower lines - but again you need a good distance to make the effort worthwhile.

Even better is stopping the dawdling into through stations. What is the point of going fast if you do the last bit at 10mph?

 

[zwk500]

Now that I think about, I'd also say between Manchester-Liverpool via Chat Moss, Leeds to York (if it's not already 200 / 125) might also be good candidates as well! The former in particular does have a lot of fast accelerating local EMU (Electric Multiple Unit) services which I believe do run at fairly high speeds (160 km/h?).

The Chat Moss definitely not, the local services already slow down 100mph trains so 125mph trains would be worse. Leeds to York is already as high as it can reasonably go, given the geometry constraints.

Further to that, I would also say Wolverhampton-Shrewsbury & Crewe-Chester (and maybe up to Llandudno Junction). Certainly if they were ever electrified, tilting Pendolinos could make the best use of the fast speeds (although whether the lines in question have as much as curves as the WCML to justify tilting I am not sure)

Wolverhampton-Shrewsbury just doesn't justfiy the costs of upgrading and maintaining the line above 100mph. Crewe-Chester is damned twisty and pretty short, so the benefit of an upgrade is very limited.

Remember, 100 to 125mph is 8sec/mile. You also generally need 3 or 4 minutes between trains so to get the benefit of an extra path you need to save 6 or 8 minutes journey time (3/4 minutes behind the first train and 3/4 minutes behind the extra one). That means to save 6 minutes you need to be able to upgrade 45 miles of 100mph running to 125mph. Now also consider an extra mile or so each side for acceleration and braking (acceleration being the harder as the power required curves upwards, 1-60 is easy, 60-100 is harder, 100-125 harder still), you really are running out of areas with 50 miles or more between stops that haven't already been upgraded.
A related question here is could you save more time by not going as slowly in other places? A lift from 50mph (72s/mi) to 75mph (48s/mi) saves half as much again (12s/mi) as the 8s/mi of 100 -> 125mph. Knocking a stop out of a 100mph section of line saves about 4-5 minutes on it's own.

Also consider the mixed traffic problems - track canted for a 125mph passenger train is going to behave very differently when a 60mph 2000 tonne freight train runs over it, or cause serious problems for passengers of a local train stopped at a heavily canted station. Look at Wolverton, on the WCML here (and this platform is only 90mph! https://www.shutterstock.com/image-photo/wolverton-buckinghamshire-england-april-11-2017-1193404771). In addition, if the railway is 2-track you will not be able to run faster than the train in front, so have you got junctions, loops, or termini at the right point so that your very expensively speeded up train does not then encounter yellow signals? Spending millions upgrading the track doesn't help if the trains ahead of you are stopping at every station.

Of course, you can remove trains from in front of you by diverting them or changing stopping patterns, but that will cost revenue so if the additional revenue from running faster worth it? Then consider the cost of maintaining higher speed track. It has tighter tolerances and needs to be inspected more often as even the smallest crack could multiply quickly. Is the value of the 125mph running repaid by train revenues?

 

[Meerkat]

Are we talking upgrading on existing trackbed, upgrading existing route with some corner cutting, or full on straighter short cuts?

 

[30907]

From previous threads, ISTR that the greatest benefit is from evening out the speed profile, as was done on the ECML to great effect and on the MML to a lesser extent (if more is reasonably possible, that might be a candidate - but I suspect I know the answer).

 

[The Planner]

From previous threads, ISTR that the greatest benefit is from evening out the speed profile, as was done on the ECML to great effect and on the MML to a lesser extent (if more is reasonably possible, that might be a candidate - but I suspect I know the answer).

Yes, a sawtooth profile isnt brilliant, especially if the speed changes are close together as a driver won't accelerate if they are braking almost immediately. Evening out a profile is better.

As @zwk500 has noted, you go for the slower speeds, loops and junctions etc as that is where the gains are.

 

[zwk500]

From previous threads, ISTR that the greatest benefit is from evening out the speed profile, as was done on the ECML to great effect and on the MML to a lesser extent (if more is reasonably possible, that might be a candidate - but I suspect I know the answer).

Yes indeed. As a theoretical case in point, compare the two speed profiles: (The straight line is the linespeed, the curve is the train speed). Which section of track do we think will be the most beneficial to raise the linespeed of?

 

[The Planner]

Yes indeed. As a theoretical case in point, compare the two speed profiles: (The straight line is the linespeed, the curve is the train speed). Which section of track do we think will be the most beneficial to raise the linespeed of?

And that is a really good case of modelling giving the wrong answers, and people not understanding them properly, as it doesnt reflect driver behaviour.

 

[zwk500]

And that is a really good case of modelling giving the wrong answers, and people not understanding them properly, as it doesnt reflect driver behaviour.

From this paper: https://www.mdpi.com/2071-1050/13/3/1394, Široký J, Nachtigall P, Tischer E, Gašparík J. Simulation of Railway Lines with a Simplified Interlocking System. Sustainability. 2021; 13(3):1394. https://doi.org/10.3390/su13031394

The figure description is:

Figure 5. Tachograph for freight (top) and passenger (bottom) trains in the section Moravany–Borohrádek. Source: Authors, based on SW OpenTrack.

 

[hexagon789]

For me, one line I can think of is Exeter to Reading via Newbury plus to Bristol then Birmingham. Whilst it might not make a big difference in journey times seeing the 800/802/220/221s go at 160-180 km/h (100-110 mph), one possible benefit of faster speed is to be able to make better use of the paths.

Exeter to Reading already permits 110 on a number of sections.

Similar Cogload Jcn (where the Berks & Hants line from Reading to Exeter joins the Bristol to Exeter Line) to Bristol has an 8.5 mile section of 110mph.

Finally, Bristol to Birmingham is 100 for long distances, much of it 90/HST 100 so already I suspect signal spacing would be an issue.

There were intentions as part of the upgrades for Operation Princess thar weren't carried out (some were, such as Birmingham to Derby) to upgrade Birmingham to Taunton to 120mph and Birmingham to Oxford to 115mph.

I suspect the usual cost/benefit ratio found it was of modest benefit to journey times for the costs involved.

BR planned to upgrade Cogload to Exeter via Taunton to 125 by 1985 to improve the journey times of the NE-SW HST services, but with cuts to those in both 1984 and 1985 it never saw fruition and the 100mph limit (already an increase over the steam era 90) has perpetuated ever since.

I do wonder how much time you would save by making as much of Bristol to Exeter 125mph. Would it even be 8 mins, let alone 10 or more?

 

[43096]

Going faster only makes better use of the paths if everything is going faster, but the B&H has Newbury locals and freight on it as well. There's also the issue of the line's geometry being quite problematic.

The B&H would only make sense if it was electrified as the current traction cannot do 125mph on diesel. If it was going to be done, then 40 years ago would have been the time, when the traction was 125mph capable on diesel!

 

[Bartsimho]

Any Linespeed upgrade I could think of is the Cornish Mainline as it takes 2 hours from Plymouth to Penzance making rail journeys into Cornwall unappealing even though the line into Plymouth is appealing.
From the Cornish Border to Penzance by rail in 2 hours but by road it is:
From Plymouth 2 hours as well
From Launceston 1 hour 30.
Most trains from the rest of the country to Plymouth are faster than the equivalent road journey but the 60mph really hurts it. Although some straightening and some passing loops would be needed to fully utilise the linespeed.

I wouldn't be surprised if Cornwall Council wanted to explore this though as they have almost finished all the Road Infrastructure upgrades to allow entry into the County

 

[Starmill]

And that is a really good case of modelling giving the wrong answers, and people not understanding them properly, as it doesnt reflect driver behaviour.

To be fair it's a reasonable reflection of driver behaviour on the Continent.

 

[The Planner]

To be fair it's a reasonable reflection of driver behaviour on the Continent.

The issue is that people expect running times based on the spikes and don't consider driveability, they then moan when a project doesn't deliver what they think it will.

 

[zwk500]

The issue is that people expect running times based on the spikes and don't consider driveability, they then moan when a project doesn't deliver what they think it will.

The article claims they're tacho traces.

 

[Nottingham59]

I find openrailwaymap and railmaps useful when thinking about this sort of question:
https://www.openrailwaymap.org/ (with max speed option selected)

Line Speeds - Rail Maps

With current traffic patterns, I would say the following:
The WCML, GWML, and ECML have already been done (where sensible), but there are a number of mainlines where 125mph running could be beneficial. I'm thinking of the (slow parts of the ) MML; Bristol-Kings Norton (where the 4-tracking ends); Bristol-Exeter; WCML north of wherever the Golborne Link eventually joins it. The MML is as twisty as the WCML, so would need tilt - maybe a home for the Pendolinos when HS2 phase 2a gets built?

But looking ahead, I think the picture changes:

• HS2 will change everything on WCML (and hopefully the MML too if the eastern stump gets built). The WCML south of Preston and the MML south of EMD should probably become a 110mph railway, running high-capacity end-doored electrified stock at low prices, like LNWR does today. And with more freight on those lines too. After HS2, the bulk of the traffic on the southern MML will be south of Leicester, which could readily be served by 350-style stock.
• ETCS will allow speeds faster than 125mph as the in-cab signalling would avoid the need for signal sighting. So the ECML and GWML should be planning now to increase speeds to around 150mph over the next 20 years, as ETCS rolls out. With all freight going via Lincoln or Westbury.
• Given that HS2 trains will not have tilt and be therefore limited to 110mph north of Lancaster, I think that maybe HS2 services to Scotland should terminate at Preston, where passengers could transfer (ideally cross-platform) to join 150mph tilting train services running Manchester-Glasgow and/or Liverpool-Edinbugh.
• We should look at upgrading Taunton-Kings Norton to 150mph running too, though the cross country route would probably need tilt at those speeds. And Marsden to Church Fenton, if the 230kph/140mph NPR tunnels every get built.

 

[zwk500]

ETCS will allow speeds faster than 125mph as the in-cab signalling would avoid the need for signal sighting. So the ECML and GWML should be planning now to increase speeds to around 150mph over the next 20 years, as ETCS rolls out. With all freight going via Lincoln or Westbury.
Given that HS2 trains will not have tilt and be therefore limited to 110mph north of Lancaster, I think that maybe HS2 services to Scotland should terminate at Preston, where passengers could transfer (ideally cross-platform) to join 150mph tilting train services running Manchester-Glasgow and/or Liverpool-Edinbugh.
We should look at upgrading Taunton-Kings Norton to 150mph running too, though the cross country route would probably need tilt at those speeds. And Marsden to Church Fenton, if the 230kph/140mph NPR tunnels every get built.

above 125mph requires a lot of upgrades to track, signalling and OLE. It's simply not going to be cost effective to do any line other than maybe Peterborough to Doncaster.

 

[Bartsimho]

above 125mph requires a lot of upgrades to track, signalling and OLE. It's simply not going to be cost effective to do any line other than maybe Peterborough to Doncaster.

You could say 4 tracking sections is more important than line speed in many places to allow the current speed to be better utilised

 

[HSTEd]

If HS2 ever reaches Manchester the defacto route from Leeds to London will switch to via Manchester.

Even 150mph over the ECML would struggle to compete on that basis - at which point why bother?

Spend the money you have for such a project on adding to the Marsden stub or between Leeds and Newcastle (possibly bypass York).

 

[zwk500]

You could say 4 tracking sections is more important than line speed in many places to allow the current speed to be better utilised

I would certainly support 4-tracking of existing mixed traffic sections over speed upgrades. Banbury to Leamington, Tamworth to Burton, and Preston to Carlisle (or off-line newbuild of passenger tracks from Oxenholme to Carlisle). would be my first places to start

 

[cle]

We also have to look at capable stock. The whole 'Project 110' was predicated on the stock having that extra 10 in the bank.

So combining places with 125 capable stock (i.e. no point upgrading 100mph stretches if that's all their current stock can offer, at least yet) - much of the MML 125mph upgrading was done with this in mind.

GWR - certainly Exeter to Taunton improvements would benefit multiple services, but then also consider pathing with new stations coming at Wellington and Cullumpton - without any capacity (loop/platform) works. B&H would be great to do where possible, it's generally fast but there are many variants (slowing/upping 10-15mph here and there) which wires would help more.

That is another factor, it would make less difference on an already electrified route such as Norwich.

 

[Nottingham59]

I would certainly support 4-tracking of existing mixed traffic sections over speed upgrades.

I agree. Though some places the four tracks can be pretty far apart, like Peterborough-Doncaster, or Gretna-Glasgow.

consider pathing with new stations coming at Wellington and Cullumpton - without any capacity (loop/platform) works.

The uncontrolled spawning of minor stations on mainlines really should be banned without loops.

 

[Tobbes]

But looking ahead, I think the picture changes:
<snip>

• Given that HS2 trains will not have tilt and be therefore limited to 110mph north of Lancaster, I think that maybe HS2 services to Scotland should terminate at Preston, where passengers could transfer (ideally cross-platform) to join 150mph tilting train services running Manchester-Glasgow and/or Liverpool-Edinbugh.

One would hope that an incoming government would build a true HSR to the Central Belt.

 

[The Planner]

The article claims they're tacho traces.

That doesnt make sense looking at them. The bottom one looks like a trace for a modelled stopping service where the top one doesnt make a lot of sense at all for a passenger train. If anything the traces are too slow for trains if its km/h.

 

[Bartsimho]

One would hope that an incoming government would build a true HSR to the Central Belt.

Thinking a bit politically if you want to win the Central Belt from the SNP it would be a good idea to propose

 

[HSTEd]

One would hope that an incoming government would build a true HSR to the Central Belt.

In the current financial climate it is likely that all resources will be diverted to pay rises for various photogenic groups (doctors, teachers, nurses etc).

Anything that is left will be spent on protecting the 'vulnerable' (which normally means triple lock increases for Pensioners).

I would not expect any significant additional government spending on infrastructure from the Labour party, given the known ideological stance of the leadership.

 

[zwk500]

That doesnt make sense looking at them. The bottom one looks like a trace for a modelled stopping service where the top one doesnt make a lot of sense at all for a passenger train. If anything the traces are too slow for trains if its km/h.

The top on makes sense as a trace for a freight train, which is what it's claimed to be. I agree the bottom service looks much more like a modelled train.