High Speed Two (HS2) discussion

[swt_passenger]

Does anyone know how close the line will come to Cubbington village.

No, but I can point you to the maps, which should give the answer:

https://www.gov.uk/hs2-phase-two-initial-preferred-route-plan-and-profile-maps

 

[Harbon 1]

Which bottlenecks do you want to widen? Say you find a pot of cash to tackle the two track viaduct at Welwyn. That's great, but then trains get stuck slightly further north as the line to Peterborough isn't four track. Tackling most bottlenecks just pushes the problem marginally further up the line.

Trying to tackle the WCML again would mean a long period of "bustitution" for long distance passengers. Building a separate line would mean virtually no disruption to current passengers.

AFAIK suburban services are gone by just after Peterborough, so widening the viaduct would, if it was built slightly away from the existing one would not move the bottleneck further north, as it is four track until Stoke tunnel, with a bit oof 3 track, the disruption would be minimal, with a couple of posessions to connect the mainline to it, and put the signals and interlocking in.

If its major works like remodeling, then buses are inevitable, but if its adding an extra track, buses aren't needed until the track comes to being linked up with the existing network, or additional junctions are being installed

 

[JamesRowden]

No figures, but I would expect the cost contribution would be fairly minimal, I seem to remember reading that fuel costs comprise ~3% of a typical TOC's expenditure (this could be total rubbish though). A TGV Duplex has a power output of 8.8 MW, an ICE3 8.0 MW - compared to a 390/1 at 5.9 MW it's not hugely higher (I realise that these trains don't run at 250 mph, but at 186 mph the power requirement should still be 5x that at 125 mph).

I expect that most trains only use maximum power output during acceleration (where power/mass is the important ratio) and then run at below maximum power output at maximum speed. Using the extra power for greater acceleration should save more time per unit energy than when at top speed (which might be limited by what the train might be rated up to rather than simply being about power). Just like when your cycling you'll put extra power in when pulling away from a junction than when your cruising at a constant speed.

 

[LexyBoy]

I'm sure that's true, it's interesting that high speed trains aren't equipped with that much extra power capacity though.

 

[steamdrivenand]

AFAIK suburban services are gone by just after Peterborough, so widening the viaduct would, if it was built slightly away from the existing one would not move the bottleneck further north, as it is four track until Stoke tunnel, with a bit oof 3 track, the disruption would be minimal, with a couple of posessions to connect the mainline to it, and put the signals and interlocking in.

If its major works like remodeling, then buses are inevitable, but if its adding an extra track, buses aren't needed until the track comes to being linked up with the existing network, or additional junctions are being installed

All this talk of upgrading existing lines and adding extra lines to current ones has made me realise that that is precisely what HS2 propose to do between Lichfield and north of Crewe.

A fair proportion of the proposed line runs cheek by jowl with the WCML and it rarely gets more than a few hundred yards away until it arches off towards Man. Air. Most of the wider gaps between the two are to allow HS2 a straighter alignment because of its higher line speed.

If you read the engineering proposals you'll see that they're going to have to take special precautions and strengthen the WCML trackbed, whilst the HS2 work is going on, to avoid slippage.

 

[LexyBoy]

On the subject of new vs improving existing routes, consider that the improvements at Reading are costing nearly £1bn, for that you get detangling of two station approaches including a section of viaduct, five new platforms and a new station building, in total covering a couple of miles. Most of the land required was already NR owned and the expansion of the station will minimise disruption - even so there are regularly weekend disruptions and a couple of prolonged blockades.

To get the kind of capacity (and image) improvements HS2 will deliver, you'd need to engage in similar projects along huge areas of the WCML, as well as purchasing land adjacent to the current line (much of which is heavily built up) in order to quadruple/hexuple the lines and to grade separate crossings. The cost of the disruption to travel must also be considered and will be considerable.

 

[rebmcr]

390s (pendolinos) are designed to be 'aerodynamically efficient' (low drag coefficient). If a train with the body of a 390 was run at 250mph rather than 125 mph the energy required per unit distance would be four times as much.

Nope, because the formula only applies whilst the vehicle is accelerating, which comprises a fraction of the time that cruising does on a long-distance rail journey. Not to mention that you're not taking into account the fact that the 250mph will get there faster.

 

[LexyBoy]

Nope, because the formula only applies whilst the vehicle is accelerating, which comprises a fraction of the time that cruising does on a long-distance rail journey. Not to mention that you're not taking into account the fact that the 250mph will get there faster.

No, the power required to propel a vehicle at 250 mph is eight times that required for 125 mph, considering aerodynamic drag only (which is the main factor at these speeds). Since you'll get there in half the time, the energy required is only 4 times that needed at 125 mph.

You also need (at least) four times the energy required to accelerate to 125 mph in order to get up to 250 mph.

 

[steamdrivenand]

On the subject of new vs improving existing routes, consider that the improvements at Reading are costing nearly £1bn, for that you get detangling of two station approaches including a section of viaduct, five new platforms and a new station building, in total covering a couple of miles. Most of the land required was already NR owned and the expansion of the station will minimise disruption - even so there are regularly weekend disruptions and a couple of prolonged blockades.

To get the kind of capacity (and image) improvements HS2 will deliver, you'd need to engage in similar projects along huge areas of the WCML, as well as purchasing land adjacent to the current line (much of which is heavily built up) in order to quadruple/hexuple the lines and to grade separate crossings. The cost of the disruption to travel must also be considered and will be considerable.

And it wouldn't just be the WCML because let's not forget that HS2 has an eastern arm too so you'd have to engage in improvement works from Brum to Derby and presumably on up to Sheffield and Leeds and I doubt the local, MML and XC customers would be any more forgiving than those on WCML.

It's interesting how the anti protaganists have hit on this constant nagging about updating what we've got, rather than going for a completely new network. I suspect they believe it chimes readily with the innate conservatism of the British. They calculate that people will be happier at the concept of existing stuff being improved whereas something brand new will be regarded as bad on principle. They also know that the average Brits time horizon is about 2 years (if not 30 seconds in some cases) and talk of stuff that takes 20 years and will provide a step change in provision is outside their understanding.

I suspect the Government hoped that the publication last week of NRs expenditure plans on future Classic improvements would be considered as the equivalent of the antis demands and would draw the sting out of such criticisms, but outside the railway world the plans hardly made an impression at all.

 

[jon0844]

http://www.bbc.co.uk/news/magazine-21231044

HS2: 20 reasons why it can take 20 years to build a railway

 

[AndyLandy]

http://www.bbc.co.uk/news/magazine-21231044

HS2: 20 reasons why it can take 20 years to build a railway

From that article:

HS2 costs £32bn. With the £15bn Crossrail...

So, 330 miles of high speed railway will cost only slightly more than double the cost of Crossrail?

I think that's incredibly good value in comparison. And it very clearly outlines the point that it's working around existing infrastructure that's expensive.

 

[steamdrivenand]

From that article:

So, 330 miles of high speed railway will cost only slightly more than double the cost of Crossrail?

I think that's incredibly good value in comparison. And it very clearly outlines the point that it's working around existing infrastructure that's expensive.

I think I heard it said on R4 this morning that they can lay 1 mile of track in a day on open ground, but tunnelling and other infrastructure adds tremendous amounts of time and cost. And that's with todays technology, things might have got even faster in 10 to 20 years time.

 

[Dave1987]

I do not believe that ERTMS considers the speed of the train infront because there is more likely to be a problem resulting in a verry serious accident.

Braking distances are determined by start speed, end and deccaleration. Since Emergency Braking exists I think that we can asume that it is the G-forces/control of the train that limit the deccaleration rather than the level of braking technology.



390s (pendolinos) are designed to be 'aerodynamically efficient' (low drag coefficient). If a train with the body of a 390 was run at 250mph rather than 125 mph the energy required per unit distance would be four times as much.

I believe ERTMS signalling does take into account the speed of trains and ensures they stay a minimum of the service braking distance apart plus a bit. I don't sign ERTMS lines so am not 100% on it. Regen braking makes a huge amount of difference in braking abilities of trains, the only think that really affects this is rail adhesion. Don't understand why people want slower trains. Taiwan have more high speed rail that we do. We are about 30 odd years behind the rest. Think how fast you can get from the north to the south of France. Ridiculous how long it takes to get from London to Manchester in this country.

 

[JamesRowden]

I believe ERTMS signalling does take into account the speed of trains and ensures they stay a minimum of the service braking distance apart plus a bit. I don't sign ERTMS lines so am not 100% on it.

I am not denying that the ERTMS that would be implemented considers the speed of the train that is being signalled. I just do not think one train is told how fast another train is going (otherwise why not just run all trains nose to tail like on a motorway). If this were possible it could solve all of the line (not station/crossing paths) related capacity problems across the country. I think that there is an issue with communicating one train's speed to another reliability. You have to think about what would happen if there was a technical fault of some sort. Displacement is easier to measure and can be backed up by sensors along the line. In order to measure the speed of the train externally continuously the displacement reading would need to differentiated which a very 'noisy' process (random signal across the true signal).

Maybe a way will be found to create an ultra reliable system that considers the speed of the train in front to maximise capacity but if not my original point of the gaps between trains needing to be directly proportional to the braking distance (plus at little [comfort zone + Length of train + signaling displacement resolution]) which is directly proportional to the square of the speed (assuming a constant decaleration rate) which means that the maximum frequency of trains at high speed would be inversly porportional to the speed of the trains (double the speed, half the capacity) (ignoring the comfort zone etc.).
--- old post above --- --- new post below ---
I have just come up with the reason why trains couldn't always virtually run nose to tail even if the speed of the one in front was known to the one behind. When the paths diverge the points will need to change between the trains and the train behind has to be at least its braking distance behind incase there is a points failure.

 

[Harbon 1]

Why is the plan to use ERTMS anyway? Surely if it's having teething issues then the it should be better to use the French system like on HS1 or does this only work on open line and not in station mouths etc?

 

[The Planner]

I believe ERTMS signalling does take into account the speed of trains and ensures they stay a minimum of the service braking distance apart plus a bit.

That is moving block, ERTMS on the Cambrian only allows one train in section between the marker boards and gives the movement authorities based on that.

 

[carriageline]

James, what would be the point in running trains nose to tail? Essentially, one train would be full, another would empty at stations?

I guess spacing them gives a nice even spread over the required demand.

 

[jon0844]

Having read the BBC '20 reasons' article, surely this is a good reason to go ahead;

Euston is being redeveloped. As part of that a section of Camden will need to be demolished.

 

[NSEFAN]

That is moving block, ERTMS on the Cambrian only allows one train in section between the marker boards and gives the movement authorities based on that.

Isn't moving block effectively just lots of very short blocks?

 

[JamesRowden]

James, what would be the point in running trains nose to tail? Essentially, one train would be full, another would empty at stations?

I guess spacing them gives a nice even spread over the required demand.

On the HS2 site it shows the Birmingham service with Old Oak Common and Birmingham Interchange as succesive stops while a Manchester service is shown as running fast from Old Oak Common to Manchester. It would be a bit of a problem if a person was planning to go to Birmingham Airport and got on the service to Manchester because it was going to leave Old Oak Common / Euston just before the Birmingham service.

Source:
http://www.hs2.org.uk/phase-two/facts-figures

 

[Nym]

Isn't moving block effectively just lots of very short blocks?

Depends on how it's implemented, but yes, pretty much...

 

[JohnCarlson]

It potentially frees up more paths on the ECML though, since it'll remove some of the speed differentials on the two track sections (e.g. a 91 running on the two track section through Stoke Tunnel area is going to catch up an EMT 158 on Liverpool - Norwich).

If everything on the ECML becomes 100mph max then that allows more services to be fitted in.

One thing I find interesting about the HS2 debate is one minute folks are saying that the existing ECML services will just carry on then the next that HS2 will free up spaces for slower services on the ECML. Some contradiction there I think.

Personally I dont think HS2 will make much difference to journey times on the ECML from north of York to London. It will improve times to Sheffield and Birmingham and the midlands which is of course good. I also suspect that while there might be a genuine HS line built between Newcastle and Edinborough and from South of Northallerton to Gateshead it wont be HS all the way,
--- old post above --- --- new post below ---

On the subject of new vs improving existing routes, consider that the improvements at Reading are costing nearly £1bn, for that you get detangling of two station approaches including a section of viaduct, five new platforms and a new station building, in total covering a couple of miles. Most of the land required was already NR owned and the expansion of the station will minimise disruption - even so there are regularly weekend disruptions and a couple of prolonged blockades.

To get the kind of capacity (and image) improvements HS2 will deliver, you'd need to engage in similar projects along huge areas of the WCML, as well as purchasing land adjacent to the current line (much of which is heavily built up) in order to quadruple/hexuple the lines and to grade separate crossings. The cost of the disruption to travel must also be considered and will be considerable.

A could of weeks ago I came up from London first class in an HST. Every time a train passed us going the other way my laptop on the table jumped in the air. I was convinced by that alone that we need a new line not just incremental upgrades of the old.
--- old post above --- --- new post below ---

The Green Party is against HS2.

So are UKIP.
--- old post above --- --- new post below ---

1. The only significant income it will make is from the extortionate fares that will be charged. In effect the only economic benefit will be the people that will have the cheaper fares in the areas that HS2 bypasses on the southern WCML.

2. I never said it would be easy to upgrade a route with extra lines or high speed running, but it would be quicker to upgrade an existing route as there wouldn't be 10 years of planning plus a further 10 of building, and there would be nearly no opposition, and nowhere would be noticeably affected in the ways the NIMBYs are saying. A line visible on the level won't seem any closer than the existing alignment did. And the most that people would lose, is a bit of their garden, which is better then their home.

3. The majority of people travel in the week, there is nowhere near as many people travelling on a Saturday than there is on any given weekday. Having a bus replacing services for half a year at will still happen if HS2 is built. The line has to pass over the WCML, and bridges will have to be built. This takes several possessions as a bridge reconstruction near me has demonstrated. Not to mention the disruption at Euston because of the complete reconstruction of the station. It doesn't take a few months to re construct a station, as St P. demonstrated and New St. will demonstrate. What's wrong with a blockade? Stopping trains over a period of reduced travel has happened and is still happening (Nottingham this summer). And for the most part, again from my own experience, the updating of a lesser used track, or the addition of an extra track on the outside on ex railway land isn't as disruptive as it is made out to be. PW have been replacing a freight line outside my house and it has taken them a week to re-lay the line (still waiting for tamping, that's being used where they're lowering the line for W10).

4. Birmingham to Leeds is very possible at the present time... Every route (London - Birmingham, Sheffield, *Manchester, Leeds etc) are already *possible. And they're not exactly long journeys either.

5. Again, closing and rebuilding will cost enough money and delays, possessions and blockades that will disrupt the WCML. The WCML will then be further disrupted with the construction works for HS2 and will be left with fewer platforms.

A while ago I was in favor of the idea of just upgrading infrastructure. But much of the existing ECML could not be upgraded to 200mph * without significant buying of new land and property. Also on many of the long straight four track sections you would have to buy extra land alongside the existing tacks, build some new tracks, then move the two center tracks apart while maintaining the overhead. That would be a nightmare.

Kings Cross is about as big as it can get. Although I would regret this personally moving it towards being more of a long along distance commuter station with services north of Doncaster favoring Euston might be the way to go.

 

[WatcherZero]

For those saying £30bn over 20 years is a waste of money, KPMG are forecasting that HS2 if built will by 2040 be generating an extra £10bn in tax for the Government every single year!

 

[JohnB57]

For those saying £30bn over 20 years is a waste of money, KPMG are forecasting that HS2 if built will by 2040 be generating an extra £10bn in tax for the Government every single year!

The KPMG press release is vague and unspecific about what precise form this additional revenue will take. I saw your similarly worded post from another forum and was a little surprised that there was no further discussion.

The £33bn will, naturally, increase significantly, as will the cost of borrowing it. And the additional tax revenue is finger in the air stuff - the figure sounds just too convenient - and is likely to fall short of that. Or be fictional in the first place. They really expect the project to be in profit by the early 40s?

 

[WatcherZero]

Based on HS2 expanding GDP by £17bn-£29bn in real terms, generating a £6-10bn increase in annual tax revenues from payroll and corporation taxes.

Richard Threlfall, Head of Infrastructure, Building and Construction at KPMG, comments on the Government’s announcement of the preferred route for phase 2 of HS2.

“Today’s announcement is good news for Britain’s transport network and for our economy.

“Our own analysis shows that better business to business connectivity will enhance productivity and employment and thereby would contribute to economic growth. Ultimately HS2 would also generate substantial additional tax revenues to the exchequer.

“We predict that a high speed rail network across the UK could boost annual economic output between £17bn and £29bn in 2040.

“Additional annual economic impacts on this scale could increase annual tax receipts by between £6bn and £10bn in real terms by 2040.”

“Our work suggests high speed rail offers a good return to the Treasury and to the taxpayer and is a cost effective approach to securing future national prosperity.

“Today’s announcement is also fantastic news for our northern city regions. It is a bold statement by the Government of its intention to redress the UK’s economic power balance. The last decade has seen a significant shift in the UK’s economic centre of gravity towards London and the South-East. In 1999 31.9% of the country’s economic productivity originated in the South-East, today it is more than 35%. Today’s news could be the first step towards shifting more power towards the Midlands and the North of the country so that the UK as a whole operates as an economic powerhouse.”

 

[jon0844]

How much did HS1 overspend by?

 

[rebmcr]

I am not denying that the ERTMS that would be implemented considers the speed of the train that is being signalled. I just do not think one train is told how fast another train is going (otherwise why not just run all trains nose to tail like on a motorway). If this were possible it could solve all of the line (not station/crossing paths) related capacity problems across the country. I think that there is an issue with communicating one train's speed to another reliability. You have to think about what would happen if there was a technical fault of some sort. Displacement is easier to measure and can be backed up by sensors along the line. In order to measure the speed of the train externally continuously the displacement reading would need to differentiated which a very 'noisy' process (random signal across the true signal).

Maybe a way will be found to create an ultra reliable system that considers the speed of the train in front to maximise capacity but if not my original point of the gaps between trains needing to be directly proportional to the braking distance (plus at little [comfort zone + Length of train + signaling displacement resolution]) which is directly proportional to the square of the speed (assuming a constant decaleration rate) which means that the maximum frequency of trains at high speed would be inversly porportional to the speed of the trains (double the speed, half the capacity) (ignoring the comfort zone etc.).
--- old post above --- --- new post below ---
I have just come up with the reason why trains couldn't always virtually run nose to tail even if the speed of the one in front was known to the one behind. When the paths diverge the points will need to change between the trains and the train behind has to be at least its braking distance behind incase there is a points failure.

ERTMS Level 2 will maintain a constant connection with the signalling centre, using a GSM-R data link. If the data link fails, the train stops itself immediately and the signalling centre will take that into account when instructing the train(s) following it — presumably stopping them too (whether or not this will cause massive problems in areas with poor radio reception is a point for debate).

Therefore it is indeed safe to run the trains as close together as (emergency braking distance)+(train length)+(comfort zone), using 2013/2014 technology. I believe that the e-braking distance specified is friction-only, which means the comfort zone would be even longer once you take into account rheostatic/regenerative/eddy-current braking.

 

[Dave1987]

How much did HS1 overspend by?

It didnt it was on time on budget

 

[Metrailway]

It didnt it was on time on budget

No it wasn't - BR quoted £2.6 billion in 1990 I think. It cost £5.8 billion in the end. People claim HS1 was on budget just like the politicians claim that the Olympics was on budget.

 

[Dave1987]

ERTMS signalling makes incredibly efficient use of the infrastructure as trains can run very close together and at much higher speed. The current infrastructure on the WCML makes ERTMS signalling very expensive. If it was installed on a purpose built very straight line ie HS2 the line could have trains running at very high speed close together (and I mean close together with regards to SBD at 250mph) so the line could be very well utilised. The the current WCML could have more stopping services so serve Watford and Milton Keynes better. HS2 is a total win win situation. With the projected outlook of the extra GDP that could be made from it, £32bn actually seems like a bargain when considering that is for the entire route from the south all the way to the north!
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No it wasn't - BR quoted £2.6 billion in 1990 I think. It cost £5.8 billion in the end. People claim HS1 was on budget just like the politicians claim that the Olympics was on budget.

When you take into account inflation I think you find it was on budget.