School me on HS2

crunchman

The problem is that the existing lines aren't even designed for 100mph.

Trains have solid axles so they don't corner well.  They go around corners because their wheels are slightly conical.  The wheel on the outside of the corner starts to ride up onto the larger part of the cone, while the inner wheel goes onto the smaller part.  The difference in circumference enables the train to corner.

However, you also need to cant (slope) the track to get gravity working in your favour.  Otherwise you wind up with the wheel flange grinding big time against the rail.  The tighter the curve, and the faster you want to travel, the bigger the cant you need.  However, there is a limit to how much you can cant the track.  In the worst case because you don't want the train to topple off the track if it become stationary.

To run at current speeds, railways run massive "cant deficiencies" which means the wheel flange is putting large stresses on the outside rail of the curve.  This costs a fortune in maintenance.  In a well managed case you have to spend lots of money replacing rails (and wheels) on a regular basis.  In an badly managed case you wind up with the Hatfield crash (where they were running at 115mph on track designed for 80mph).

I work for London Underground Track, and we spend a fortune maintaining ancient infrastructure.  We have a lot of very tight curves.  Until we improved our track lubrication, there was a time when we were replacing rails at some sites every six months.  Even now, they will need replacing every few years.  I know of locations of straight track where rails lasted 60 years!  If you run a railway on with lots of curves it is a lot more expensive to maintain.

If you keep the existing lines for trains doing less than 100mph the maintenance on those lines becomes a lot cheaper because you are not running way beyond the design of the track curvature.  If you build a new line for the high speed train passenger trains you can do this on the existing lines.

Also, the capacity argument is valid because you currently have 120mph passenger trains on the same lines as local trains and freight trains.  Because of the difference in speeds, you have to leave big very gaps in service.  If you were to slow the existing passenger trains you could add more capacity but no-one would be willing to accept that.  With the fast trains elsewhere, you can run everything on the existing lines at similar speeds, and increase capacity for local trains, and freight services.  This means that the capacity increase is not just the extra capacity of HS2 but the extra capacity you have created on the existing lines by removing the need for big gaps in the service.

Having said all that, the business case benefits for HS2 have almost certainly been exaggerated over the 30 or 50 year time frame that they have put on it - if nothing else because the costs will overrun.  However, we need to think long term like the Victorians.  They built lines we are we are still using 150 years later.  If we build a new line now, you would expect it to still be there long after the term used in the official business case ends - and you would still be getting benefit from it.  This is what is being missed in a lot of the debate.

Personally, I think you might be better off designing for 160mph rather than 200mph+.  I'm not sure the extra costs justify the benefits of the extra speed, but you do need to build it.

johnnyurq

Yes indeed @Phil_aka_Pip not all of Beeching's cuts are suitable for reversing willy nilly and a close look at each area and to apply the 50 or so years of hindsight would be a sensible approach.

No doubt each area could make a case for or against routes being reinstated based on whether it will create wealth and jobs versus despoiling an area.

It is a very complex situation and I think that is why we need to be careful about getting the best possible solution/solutions as what happens here will resonate down the years for good or ill.

I am afraid based on all the info out there I cannot in all honesty accept HS2 is the right way to go, in fact I believe that it will create more problems than it will solve.

Roland

johnnyurq said:

It is a very complex situation and I think that is why we need to be careful about getting the best possible solution/solutions as what happens here will resonate down the years for good or ill.

I am afraid based on all the info out there I cannot in all honesty accept HS2 is the right way to go ...

That's why it needs proper consideration.  @crunchman makes some very relevant points about technology and capacity, and I understand @Bucket 's point about environmental impact (I was born within a few miles of the proposed route and know the area well). None of us has the whole picture. That's why I'm pleased that we can have a debate about such things on this forum.  What worries me is that in the press, and across the country, it will become a polarised stand-off based on a couple of cliche'd insults.

johnnyurq

For sure @Roland.

Party lines and loyalties shouldn't enter into it and any organisation/lobby groups too close to it as to have an agenda or profit too much from it should be distanced from the process.

Descending to insults would not be productive at all, a dispassionate gather and collating of the facts would be better.

The difficulty as I see it is finding a truly independent arbiter to make sensible recommendations given how high the stakes are.
 

Jalapeno

I think it's a busted flush tbh - the Government can't keep trotting out "It's vital for the economy" line without a compelling base of evidence (which so far has been "Trust me" ......)

I live nearer the current West Coast mainline (I can see it form the bedroom) - so if anything I should be for all it on a NIMBY basis, but I can't see the argument myself - there's so many fundamental errors (like forgetting a Heathrow link, ripping up Camden & Middx, Bucks, Beds, Northants and points north).

Still don't know why they don't resurrect Great Central line- it exists - so there's little environmental issues to get in the way, and costs are similar.

mike257

"To run at current speeds, railways run massive cant deficiencies"

Easily solved. Our current government has plenty of cants they could spare.

Jalapeno

Oh and the Stop HS2 organisation don't have to try hard - they keep getting gifted Network Rail / Government mistakes.

It the Telegraph AND Mandleson agree - there has to be something fundamentally wrong

Phil_aka_Pip

mike257 said:

"To run at current speeds, railways run massive cant deficiencies"

Easily solved. Our current government has plenty of cants they could spare.

LOL awarded. Makes more sense when a Londoner says it

Clarky

maybe they could spend a tiny percentage of that 80bn by comming up with some plague that will wipe out 4 in 10 people..

saves loads of money, and won't need to expand anything at all

plenty of jobs,  houses, roads, trains, NHS etc for everyone that's left..

Phil_aka_Pip

The Black Death European tour of 1348 was quite successful ...

Clarky

awesome... we have a solution..

ICBM

Jalapeno said:

It the Telegraph AND Mandleson agree - there has to be something fundamentally wrong

Actually I'm not sure which I find more worrying… agreeing with the Torygraph, or Mandleson.

Phil_aka_Pip

If the Torygraph and Mandelson agree on anything it surely must be proof that in higher mathematics they have found theorems that are both true and false at the same time and within the same set of parameters. The space/time continuum is not curved, it is fundamentally bent.

Jalapeno

They agree with each other is surely the key - so summat's fundamentally wrong !

ESBlonde

I am reminded of the (wealthy) victorians who all had a NIMBY attitude to those newfangled railways until they realised what it could do for them. Then it became a status symbol to have the line across your land!

It seems that 'upgrading' the current network or even maintaining it will result in huge delays most weekends for the next decade or so.

Not many years ago we all raved about working from home and using 'video conferencing' only to have it fall from favour for many businesses.

Building lots of houses will ruin the bloated value of property upon which much of our present economy and pension system relies.

Accurately predicting transport needs ahead of time is notoriously difficult indeed many of our great canals were built late when people jumped on the bandwagon only to be superceeded by rail a decade or so later. Whilst some traffic has now moved to road in the late 20 century there needs to be solid backbone of rail and we have woefully  under invested in that for about 75 years. It should not be considered as the only additional infrastructure either but as the figurehead project and then private investors build plug in routes to spread the good.

But what do I know, even the professionals can't agree and I think @Roland hits several nails with his post.

Jalapeno

It's wrong to portray anti-HS2 arguers as luddite NIMBYs - most are all for rail expansion (I am) - just that this is a white elephant.

HS2 is an answer to the wrong question ("If the French have one why can't we?") - UK is a lot smaller, the population centres are also smaller & more numerous, and they are much closer together.

Phil_aka_Pip

btw @Jalapeno I can't see what's wrong with NIMBYism. If you paid good money to live somewhere nice the last thing you'd want is someone spoiling it for you.

crunchman

Jalapeno said:

HS2 is an answer to the wrong question ("If the French have one why can't we?") - UK is a lot smaller, the population centres are also smaller & more numerous, and they are much closer together.

That's one of the reasons I said I prefer to would build it for a speed of 160mph and not 200mph plus.  It's a high enough speed to get anywhere in the UK in a sensible time, and it would save on your costs.  Not sure how much it would save on construction costs but it would definitely save on maintenance and ongoing energy costs.

You do need to build it because of the capacity issue (which I covered in my post above).

ICBM

Jalapeno said:

It's wrong to portray anti-HS2 arguers as luddite NIMBYs - most are all for rail expansion (I am)

Same here… although I'd be slightly pissed off if they put the railway back into my village directly on the old track since I live on the former station site and it would literally be in my back yard .

Clarky

Phil_aka_Pip said:

If the Torygraph and Mandelson agree on anything it surely must be proof that in higher mathematics they have found theorems that are both true and false at the same time and within the same set of parameters. The space/time continuum is not curved, it is fundamentally bent.

does this also mean that Mandleson is not curved, but fundamentally bent too?