Are We Making a Mistake with HS2 Gauging?

[whhistle]

So I was thinking about this the other day.
HS2 stock will be unique to that line, unlikely to be used anywhere else after it's life on HS2.

So why (apart from additional cost) are we not widening the track, creating a bigger gauge and building for double deck trains?

Surely the additional cost would be outweighed by the benifits in the future?

 

[gazthomas]

Take a look here:

http://assets.hs2.org.uk/sites/defa...y/pdf/P2C40_HS2 operation and train types.pdf

For HS2 trains that don't go onto "classic" lines double deck trains are an option.

 

[JamesT]

So I was thinking about this the other day.
HS2 stock will be unique to that line, unlikely to be used anywhere else after it's life on HS2.

So why (apart from additional cost) are we not widening the track, creating a bigger gauge and building for double deck trains?

Surely the additional cost would be outweighed by the benifits in the future?

HS2 is being built to the European standard, so in principle we can get cheap off the shelf trains, including double deck. Although they won’t be usable anywhere else in this country, they could be sold abroad if anyone wanted a used high speed train.

The first batch of trains will be the classic compatibles which will be usable on the rest of the UK network by definition. Though as we’ve seen with the scrapping of the 373s, an end of life HS train may not be worth reusing.

 

[MarkyT]

In phase 1 all HS train apart from the fully segregated London - Birmingham ones at only 3 train per hour will have to be 'classic compatible' or 'conventional network compatible' in the latest terminology. "But doesn't it only go to Birmingham?". Not at all. From day one, the majority of trains on the new line south of Birmingham will go on to destinations in the North West of England and Scotland, using conventional lines to complete their journeys and replace the fastest schedules on the WCML, saving at least 20 minutes. Phase 2A in the north west will extend the new line to Crewe, so Manchester, Liverpool and Scottish trains can save even more time but will still use conventional tracks for the final parts of their journey. Only at Phase 2B will the full dedicated network to Manchester and Leeds be complete and, while larger trains between these cities and London and Birmingham will then be possible, there will still be an ongoing need for conventional network compatible trains to serve Crewe-Runcorn-Liverpool, Stafford-Stoke-Macclesfield, Warrington-Wigan-Preston-Lancaster, Preston-Carlisle-/other intermediate stations/-Glasgow and Edinburgh, Chesterfield-Sheffield, York-Darlington-Durham-Newcastle. At Phase 1, HS2 has decided to order a common fleet of all conventional compatible units. At Phase 2B, as demand builds up and new routes are added, a considerable increase in fleet size will be required. Some larger full European gauge units could be ordered at that time for the captive routes, even double deckers if a suitable design is available and is required for capacity.

 

[HSTEd]

Still think the loading gauge is too small.

Should have been built to permit a Shinkansen width cross-section.
With swing out loading bridges for the Classic Compatibles like those used on Mini Shinkansen.

 

[Ianno87]

Still think the loading gauge is too small.

Should have been built to permit a Shinkansen width cross-section.
With swing out loading bridges for the Classic Compatibles like those used on Mini Shinkansen.

...why? Such things look clever, but no doubt add to dwell times and risk unreliability. And just rules out being able to buy standard European stock.

HS2 will have capacity for 18 400m long trains every hour each way. If that's not enough of a capacity uplift then I don't know what is...

 

[HSTEd]

...why? Such things look clever, but no doubt add to dwell times and risk unreliability. And just rules out being able to buy standard European stock.

The classic compatible trains (which are the ones with the loading bridges) already can't be standard European stock.
And we could just buy some variation of standard Japanese stock instead.... its not really a massive issue

HS2 will have capacity for 18 400m long trains every hour each way. If that's not enough of a capacity uplift then I don't know what is...

There is never enough capacity uplift in the context of relatively short, quick journeys.
The higher you can pile it, the cheaper you can sell it for.

A 400m TGV Duplex unit (as has been proposed before using AGV technology) has a capacity of like 1350 people, a double deck Shinkansen width unit could push it up to ~1720

 

[Chester1]

I think most people don't realise that the trains running London-Birmingham in 2026 will be cascaded in 2033. The single or duplex decision will probably depend on intial demand. If demand in the first year exceeds expectations then duplex may be specified in the tender. Perhaps shorter duplex sets with an option for extra coaches might work? Tbh, its too early to think past the phase 1 order.

 

[gallafent]

A 400m TGV Duplex unit (as has been proposed before using AGV technology) has a capacity of like 1350 people, a double deck Shinkansen width unit could push it up to ~1720

Really? Using only wikipedia as a reference, I find that the Japanese loading gauge is 3.38x4.49m (wxh). Does that really provide such a capacity uplift compared to the 3.15x4.65m of European GC gauge? (or is HS2 being built to something smaller than that?) … the extra 23cm width is clearly not enough for an extra seat across the train, and the taller the better (clearly) to allow decent headroom in a double-deck train…

 

[edwin_m]

Quick image search shows that Shinkansen has 2+3 seating, at least in some part of the train. It doesn't look especially spacious (although it does have armrests!).

 

[Domh245]

Quick image search shows that Shinkansen has 2+3 seating, at least in some part of the train. It doesn't look especially spacious (although it does have armrests!).

An important thing to consider here is anthropometrics. Checking ISO/TR 7250-2:2010 reveals that 95th percentile Germans (as there isn't a UK data set) have an elbow-elbow breadth of 555mm (M+F) and a sitting hip breadth of 460mm (F). 95th percentile Japanese have 486mm (M) elbow breadth and 398mm (F) sitting hip breadth. Those sort of differences could add up

 

[Ianno87]

Quick image search shows that Shinkansen has 2+3 seating, at least in some part of the train. It doesn't look especially spacious (although it does have armrests!).

Go on the 1964 Shinkansen at the NRM to see how tiny the seats are. Definitely not suited to the 'build' of the typical Brit!

There is never enough capacity uplift in the context of relatively short, quick journeys.
The higher you can pile it, the cheaper you can sell it for.

A 400m TGV Duplex unit (as has been proposed before using AGV technology) has a capacity of like 1350 people, a double deck Shinkansen width unit could push it up to ~1720

To put it in simple context the existing WCML Fast Lines have 15tph with train lengths up to 270m: About 4km worth of train capacity every hour. Probably about the same on the ECML Fast Lines.

HS1 will *add* up to a further 7.2km of train length on top of this. That's something like 80% more long distance capacity between the Midlands/North and Euston added by HS2. That in itself is a colossal uplift likely to accommodate growth for many, many years, without having to add cost by making the entire route and its associated structures wider. You've also got to think about the station infrastructure needed to disgorge that number of people at the end of the line, and board in a timely manner. I'm sure the existing 400m trains are enough of a challenge!

 

[The Ham]

To put it in simple context the existing WCML Fast Lines have 15tph with train lengths up to 270m: About 4km worth of train capacity every hour. Probably about the same on the ECML Fast Lines.

HS1 will *add* up to a further 7.2km of train length on top of this. That's something like 80% more long distance capacity between the Midlands/North and Euston added by HS2. That in itself is a colossal uplift likely to accommodate growth for many, many years, without having to add cost by making the entire route and its associated structures wider. You've also got to think about the station infrastructure needed to disgorge that number of people at the end of the line, and board in a timely manner. I'm sure the existing 400m trains are enough of a challenge!

That 80% growth in capacity will effectively roll the clock back on overcrowding from today's figures to about 10 years ago (not allowing for increases in rolling stock capacity and based on UK wide passenger numbers). As such, if it opened today HS2 and the lines it releases capacity on would look about as busy as they did at privatisation, which although much less busy than today are likely to be far from empty.

Add in the journey time savings and the fact that rail travel could still grow a bit between now and HS2 opening and I can see why some are asking the question, why not build it to allow for a higher capacity of train to run.

 

[edwin_m]

There would also be more capacity on the existing route, because the remaining trains will all be running at a more similar average speed.

Wider trains would be unable to run onto the existing infrastructure so would limit HS2 services to those places that can justify a dedicated high speed line. Moreover, the platforms would have to be further from the track to make room for wider trains, so the classic compatibles would need much larger extendable steps than they will need anyway and standard Euro-trains couldn't run without extending steps. Along with the discomfort of 2+3 or 3+3 seating, I suggest if you wanted to build for hypothetical extra capacity it would be better to keep the width the same and increase the height to allow a double decker with flat ceilings or even a triple-decker.

However, if more high speed capacity is needed then there would probably be more benefit in building a new line more directly from London to near Leeds and transferring the London to Leeds and north-east trains onto that. That way those trains would be quicker and there could be a HS station somewhere around Peterborough/Cambridge.

 

[Chester1]

That 80% growth in capacity will effectively roll the clock back on overcrowding from today's figures to about 10 years ago (not allowing for increases in rolling stock capacity and based on UK wide passenger numbers). As such, if it opened today HS2 and the lines it releases capacity on would look about as busy as they did at privatisation, which although much less busy than today are likely to be far from empty.

Add in the journey time savings and the fact that rail travel could still grow a bit between now and HS2 opening and I can see why some are asking the question, why not build it to allow for a higher capacity of train to run.

The captive sets might be duplex units, we don't know yet. Shinkansen seat width and legroom are too small for the UK. Also, growth on the WCML after HS2 is likely to be from local and regional journeys and further capacity on HS2 won't change that.

 

[The Ham]

There would also be more capacity on the existing route, because the remaining trains will all be running at a more similar average speed.

Wider trains would be unable to run onto the existing infrastructure so would limit HS2 services to those places that can justify a dedicated high speed line. Moreover, the platforms would have to be further from the track to make room for wider trains, so the classic compatibles would need much larger extendable steps than they will need anyway and standard Euro-trains couldn't run without extending steps. Along with the discomfort of 2+3 or 3+3 seating, I suggest if you wanted to build for hypothetical extra capacity it would be better to keep the width the same and increase the height to allow a double decker with flat ceilings or even a triple-decker.

However, if more high speed capacity is needed then there would probably be more benefit in building a new line more directly from London to near Leeds and transferring the London to Leeds and north-east trains onto that. That way those trains would be quicker and there could be a HS station somewhere around Peterborough/Cambridge.

I didn't say I agreed with the question, I said that could see why people are asking the question. I would personally rather see HS2 do well and see more HS lines open up to cater for the long distance markets. Possibly to the extent that some regional lines are converted to allow the same (full) sized trains as HS2 to run on them.

 

[edwin_m]

Possibly to the extent that some regional lines are converted to allow the same (full) sized trains as HS2 to run on them.

That's highly improbable even for UIC gauge at current speeds. To increase the track spacing you have to acquire extra land, modify all the track, signalling and electrification along at least one side of the line and do something to every station and nearly every structure, all while keeping some sort of service running. Far cheaper and easier just to build a new line.

 

[MarkyT]

That's highly improbable even for UIC gauge at current speeds. To increase the track spacing you have to acquire extra land, modify all the track, signalling and electrification along at least one side of the line and do something to every station and nearly every structure, all while keeping some sort of service running. Far cheaper and easier just to build a new line.

One method of improving clearance could be to build a new single track alongside an existing double track. Then convert the existing railway to a single track using former double track structures to gain greater clearance. Still very expensive though. Platforms to move, all classic size trains remaining on the route must have extending steps etc...

 

[swaldman]

As a big guy, I find Shinkansen 2+3 to be pretty comfortable - it's probably similar seat sizes to standard class 2+2 in the UK. However, it helps that shinkansen trains have lovely seat pitch - it's all airline-style, but you can stretch your legs out and barely reach the next seat. The tray tables are big enough to comfortably use a laptop without having it in your lap. The same seat width would probably feel a lot more claustrophobic if there was a seat back a few inches from your nose. And obviously size isn't everything, as some people won't like being between two others, or two from the aisle.

 

[quantinghome]

We need to bear in mind that UIC gauge double decker trains can seat up to 140 passengers (SNCB M6 carriage) in reasonable comfort. With 400m long trains that's a heck of a lot of seats per train. Are we that desperate to avoid using double deckers?

 

[The Planner]

The captive sets might be duplex units, we don't know yet. Shinkansen seat width and legroom are too small for the UK. Also, growth on the WCML after HS2 is likely to be from local and regional journeys and further capacity on HS2 won't change that.

Ten whole pounds sterling that Captive sets are never built.

 

[swaldman]

Shinkansen seat width and legroom are too small for the UK.

Shinkansen legroom is *much* better than any I've encountered in the UK.

 

[quantinghome]

Ten whole pounds sterling that Captive sets are never built.

A quick look at HS2 journey times and frequencies indicates there would be a need for 35-40 trains on captive routes. Most of these would be 400m-length. Surely that's a big enough fleet for it to be worthwhile?
Thinking of other reasons against a captive fleet:
1. Advantages of a common fleet - but then most other countries have a variety of HS stock
2. The net increase in number of trains required to run the Phase 2 timetable compared to Phase 1 is not sufficient to justify purchasing captive over compatible stock. Don't have the numbers on this but I'd imagine it's not small.

 

[Chester1]

A quick look at HS2 journey times and frequencies indicates there would be a need for 35-40 trains on captive routes. Most of these would be 400m-length. Surely that's a big enough fleet for it to be worthwhile?
Thinking of other reasons against a captive fleet:
1. Advantages of a common fleet - but then most other countries have a variety of HS stock
2. The net increase in number of trains required to run the Phase 2 timetable compared to Phase 1 is not sufficient to justify purchasing captive over compatible stock. Don't have the numbers on this but I'd imagine it's not small.

I think it really depends on passenger numbers in the first year and the quality of the phase 1 trains. If demand is higher than expected or the classic compatible units are disappointing then a captive fleet would make more sense than a follow on order.