ECML Speed - Will trains ever reach 140mph?

[Energy]

This might be a bit off topic, but can’t GWML do 140mph, specifically between just outside Acton all the way through to Didcot, as the OHLE was engineered to do it, not sure about ETCS on the GWML though

140mph was planned, its why the OHLE and IETs were specced for 140mph (on electric). ETCS was planned under the Great Western Modernisation Programme but was scrapped. Its why coupling takes ages on the IETs as its really slowed down by the implementation of GW's legacy ATP system.

 

[hexagon789]

This might be a bit off topic, but can’t GWML do 140mph, specifically between just outside Acton all the way through to Didcot, as the OHLE was engineered to do it, not sure about ETCS on the GWML though

It's not as simple as activating as just activating some form of cab signalling to 'give' the extra speed.

 

[zwk500]

This might be a bit off topic, but can’t GWML do 140mph, specifically between just outside Acton all the way through to Didcot, as the OHLE was engineered to do it, not sure about ETCS on the GWML though

No. The points aren't swingnose and the signalling isn't capable of it, among other things.

 

[Sonik]

No. The points aren't swingnose and the signalling isn't capable of it, among other things.

Is 125mph the limit for frog S&C?

If it is I can see how upgrading to 140mph could get very expensive for a small gain

 

[zwk500]

Is 125mph the limit for frog S&C?

If it is I can see how upgrading to 140mph could get very expensive for a small gain

That's what I've been led to believe from other posters on here.

 

[Bald Rick]

Is 125mph the limit for frog S&C?

Strictly speaking it is the limit for no discontinuity in the rail in normal service.

 

[RichW1]

This is more of a thinking exercise. It is my opinion that groupthink has prevented progress here. The following makes one question it all:

In the 1980’s/90’s the timetables to York stated 1hr45 regularly. An HST I was on did it in 1hr40mins. 91’s managed it in 1hr39. Now, over-speeding would have helped the HST, but it would not have achieved a 140mph standard speed where it would have been possible, and acceleration and braking was not as good as today. Further… London to Newcastle times for a best of 2hrs39 and done in 2hrs35. The record run did ‘up to 140mph’ with an HST at 2hrs19mins. I accept the line was cleared for that record run. So… all that without 140mph running as standard where obtainable. To Edinburgh would save 15 minutes with 140mph running. Considering Edinburgh services are so damn slow at 4hrs 15 in reality, timetabled for 4hrs20 or so. 15 minutes (or more) is significant.

So I would posit that we are being a little under-ambitious here and overly negative. The difference between 110mph and 125mph is large to Edinburgh or Glasgow on the West Coast (half an hour to 40minutes in fact). Now time spent above 140mph would be less, but the 15 minute addition and a 3hr45 minute London-Edinburgh time as stated back in the 1980’s as a target is possible. That is half an hour better than standard and 15 minutes better than the current best. Edinburgh deserves this at the very least. I fly a lot between London and Edinburgh since 2013. A 3hrs30 time (if targeted) may see me change my mind (but still too long on today’s uncomfortable trains). My point being, are we not being a little too negative and downplaying the time savings with 140mph running? There’s plenty of spots and it is a not-so-populated route with plenty of flat land too that could facilitate some limited interventions.

We can do better than we are, we can do better than this. The lack of ambition drains the life out of me regards Britain’s railways. The engineers of old and in retirement or sadly passed I really mourn.

 

[zwk500]

My point being, are we not being a little too negative and downplaying the time savings with 140mph running? There’s plenty of spots and it is a not-so-populated route with plenty of flat land too that could facilitate some limited interventions.

The issue is as speed rises, the cost rises faster. It's a curve so limited interventions that yield limited benefits are less worth doing at higher speeds than by eliminating slower spots.

We can do better than we are, we can do better than this. The lack of ambition drains the life out of me regards Britain’s railways. The engineers of old and in retirement or sadly passed I really mourn.

We had the ambition to build a 400kph railway from London to Birmingham, and 300-350kph from Birmingham to Manchester, Wigan, Leeds and York. Stevenson would have had a heart attack if you'd told him his loco would be outdone by a factor of TEN when he built the rocket. It wasn't the rail industry or the engineers who've canned HS2. The Victorians were able to get past their NIMBY's because the politicians saw the value of rail connections.
Also, the rail industry and engineers delivered a high speed line from the heart of London to the Heart of Paris in 2007. They did that on an almost completely new alignment. After a certain point you've patched something up as much as it will bear, and you need to get a new start.

 

[ainsworth74]

The issue is as speed rises, the cost rises faster. It's a curve so limited interventions that yield limited benefits are less worth doing at higher speeds than by eliminating slower spots.

Which brings me back round to what I said earlier in this thread. We've already eeked out the easy wins, those that are cost effective in the 60s, 70s, 80s and 90s. The only ones left are the big jobs like sorting Morpeth, perhaps Digswell, doing the signalling for 140mph running, etc. All expensive jobs which net us perhaps fifteen twenty minutes. This is, of course, not to be sniffed at. But then we also now have somehow path these new 140mph services around all the freight and local/regional services which also use the ECML as well as semi-fast LNER services. None of this is impossible but it does inexorably start to lead you towards saying "lets just build a new railway" and if you're building a new railway it's going to be high speed.

This is, of course, the approach that has been taken in many other countries and one of the reasons is that it makes sense....

 

[Bald Rick]

An HST I was on did it in 1hr40mins. 91’s managed it in 1hr39.

Not since On Train Monitoring Recorders have been mandatory have such times been achieved.

So… all that without 140mph running as standard where obtainable.

It wasn’t standard, far from it.

For the record, 140 saves 3 seconds a mile over 125. There are roughly 230 miles of 125 railway on the ECML between Kings Cross and Edinburgh (Down line), spread across 21 separate 125mph sections, over half of which are 6 miles or shorter. If all the 125 was made 140, and even assuming we can break the laws of physics and have instant acceleration and deceleration, it would save 11.5 minutes. In reality it’s going to be about 8 minutes, assuming that all the existing 125 could be made 140. Which it can’t.

We had the ambition to build a 400kph railway from London to Birmingham, and 300-350kph from Birmingham to Manchester, Wigan, Leeds and York.

This. With HS2b to Golborne, London to Edinburgh would have been about 3h30 - 3h40. I’ll stick my neck out here, and say I reckon that if HS2 Phase 2a gets built, then the cost of getting 2b to Golborne built and delivering that 3h30 - 3h40 timing would be cheaper than rebuilding 230 miles of the ECML for 140mph… which wouldn’t achieve 3h40 anyway.

== Doublepost prevention - post automatically merged: 28 Sep 2023 ==

This is, of course, the approach that has been taken in many other countries and one of the reasons is that it makes sense....

Amen.

Here Endeth the thread!

 

[hexagon789]

Considering Edinburgh services are so damn slow at 4hrs 15 in reality, timetabled for 4hrs20 or so. 15 minutes (or more) is significant.

Over 90.7mph average, hardly 'slow' given how much of the route is not 125mph.

The planned ECML recast is set to reduce that to 4hrs05-4hrs 10 for the fast services, with no increase in linespeed whatsoever.

 

[Arkeeos]

Isn't the ECML almost at capacity? Increasing the speed would decrease the capacity of the line and could cause more overcrowding, So is there even capacity to do that?

If the HS2 eastern leg ever goes ahead, then its unlikely that there would need to be a reason to increase the speed.

 

[alf]

Strictly speaking it is the limit for no discontinuity in the rail in normal service.

Why is 125 mph the upper limit for frog S&C as stated above ?

What research has determined this?
Is this apparent ‘can’t be done here’ edict backed by science?

It would be interesting to know if other countries have this edict & whether any work has been done on analysing if lower axle loads would allow a gap at speeds above the 125 mph ‘rule’.

What specially happens at 126 mph that doesn’t happen at 125?

 

[snowball]

If the HS2 eastern leg ever goes ahead, then its unlikely that there would need to be a reason to increase the speed.

If I remember correctly an increase in the top ECML speed to 140 was promised in the Integrated Rail Plan, almost two years ago now, precisely as a sop for the dropping of the HS2 eastern leg, but it seems clear from this thread that nothing has happened since then to progress the proposal.

 

[HSTEd]

If I remember correctly an increase in the top ECML speed to 140 was promised in the Integrated Rail Plan, almost two years ago now, precisely as a sop for the dropping of the HS2 eastern leg, but it seems clear from this thread that nothing has happened since then to progress the proposal.

It is questionable whether the performance ascribed to the ECML at 140mph in that report is actually achievable.

It was most likely added by people with no real knowledge of the situation who hold the common position that upgrades are cheaper than new construction for what you get.

 

[Arkeeos]

If I remember correctly an increase in the top ECML speed to 140 was promised in the Integrated Rail Plan, almost two years ago now, precisely as a sop for the dropping of the HS2 eastern leg, but it seems clear from this thread that nothing has happened since then to progress the proposal.

They have only just started reviewing options to get HS2 to Leeds, god knows why they are only starting it now (the original eastern leg is also included in those options)

The ridiculous Newark proposal (which I don’t even think is feasible) would presumably come with upgrades to the ECML.

 

[Sonik]

Strictly speaking it is the limit for no discontinuity in the rail in normal service.

Speaking of which, is it the reduction of the number of noses to weld that makes single lead junctions cheaper to maintain? I've often pondered what the logic was otherwise.

And if so, would there be a maintenance benefit from putting in swing nose S&C (capital costs and space aside) or is HS stuff just more maintenance intensive full stop?

Bit OT but I'm thinking of the possible cost trade-offs when doing speed upgrades.

 

[trebor79]

The ridiculous Newark proposal (which I don’t even think is feasible) would presumably come with upgrades to the ECML.

What is the Newark proposal? Tie into the ECML there? I guess they could reuse the formation of the branch to Bottesford junction, it's not really been built on and is almost completely straight other than the old junction at the Newark end. Some work might be required around the gypsum mines.

 

[Arkeeos]

What is the Newark proposal? Tie into the ECML there? I guess they could reuse the formation of the branch to Bottesford junction, it's not really been built on and is almost completely straight other than the old junction at the Newark end. Some work might be required around the gypsum mines.

Its a bypass line east of Nottingham to the ECML, which would require jamming loads of trains through Nottingham station. If they are going to decrease the TPH on the bypass in this plan, then they are getting way less value for everything that they would have otherwise connected to.

 

[trebor79]

Its a bypass line east of Nottingham to the ECML, which would require jamming loads of trains through Nottingham station.

Crikey. That does sound a bit mad, although possibly not as mad as building a mega station at Toton.

 

[HSTEd]

Crikey. That does sound a bit mad, although possibly not as mad as building a mega station at Toton.

Fairly certain a station at Toton is far more feasible in an engineering sense than trying to turn Nottingham station into a HS2 compatible station.

I've been staring at maps of that area for longer than I care to admit. There is no way to get a suitable, capacity, length and loading gauge station into that area without tearing the whole station and a lot else besides apart.
It would cost several times what Toton would cost.

The attacks on the stations at Toton and Meadowhall seem to have been more about Nottingham and Sheffield retaining their regional hegemony than anything else.

 

[trebor79]

Fairly certain a station at Toton is far more feasible in an engineering sense than trying to turn Nottingham station into a HS2 compatible station.

Oh I agree. It's just that by the time you've driven to Toton (on fairly slow/crap roads), parked you car and walked to the station you might as well have just gone from Nottingham, Derby or Leicester.

 

[Bryson]

The attacks on the stations at Toton and Meadowhall seem to have been more about Nottingham and Sheffield retaining their regional hegemony than anything else.

I don't know about Nottingham but I can confirm that Sheffield City Council are regularly opposed to any significant development outside of the city centre.

The HS2 Station at Meadowhall was a red rag to a bull (even though for regional connectivity it was by far the better location).

 

[HSTEd]

Oh I agree. It's just that by the time you've driven to Toton (on fairly slow/crap roads), parked you car and walked to the station you might as well have just gone from Nottingham, Derby or Leicester.

I'm not really so sure, unless you are right next to the railway station.

From much of Nottingham Toton isn't that much further away than Midland by road transport, its a matter of a few minutes in it by car.

Toton is a lot handier for the ring road and the M1 after all.

 

[Arkeeos]

Toton is fine, Meadowhall station is honestly better just because the alignment is better for funneling people from Doncaster, Rotherham and Sheffield to the station along a single straight line. Nottingham station is on an awkward stub so im not sure where else a hs2 station could go.

Toton has the advantages that its pretty easy to get to no matter where you are in east midlands, from most places its 1 frequent train ride away. and the aforementioned M1 connection is nice.

 

[cmeads]

Strictly speaking it is the limit for no discontinuity in the rail in normal service.

 

[Bald Rick]

Why is 125 mph the upper limit for frog S&C as stated above ?

What research has determined this?

I don’t know - I’m not a track engineer or a metallurgist.

Is this apparent ‘can’t be done here’ edict backed by science?

I’m sure it is.

It would be interesting to know if other countries have this edict & whether any work has been done on analysing if lower axle loads would allow a gap at speeds above the 125 mph ‘rule’.

I’m not aware of any other countries who allow this, at least not with rail sections the size we have.

== Doublepost prevention - post automatically merged: 30 Sep 2023 ==

What specially happens at 126 mph that doesn’t happen at 125?

Again, I don’t know. But presumably it’s about risk rather than absolute. In the same way that when you drive at 31mph in a 30 area the world doesn’t stop.

 

[trebor79]

Aren't switches designed such that where trains are running in the "normal" direction the section of rail just before the gap is slightly raised relative to the section after the gap? At high speeds that "jump" is going to introduce all sorts of wheel/vehicle dynamics that could lead to a derailment I suppose. As well as the increased impact loads on track and wheel.

 

[zwk500]

Aren't switches designed such that where trains are running in the "normal" direction the section of rail just before the gap is slightly raised relative to the section after the gap? At high speeds that "jump" is going to introduce all sorts of wheel/vehicle dynamics that could lead to a derailment I suppose.

How does that work on bi-di lines?

As well as the increased impact loads on track and wheel.

This is the key part - the force of impact is a function of the square of the speed. So if you took the impact of the force at 60mph and then doubled the speed to 120mph you'd have a force 4 times greater (square of 2), but if you tripled the speed to 180mph you'd have a force 9 times greater (square of 3). That's a hell of a lot of force on both the wheel (which tends to be the softer part) and the nose on the crossing (which is very thin and vulnerable to cracking).