Double decker trains

[CardiffKid]

I know there have been various threads about this before but The Times are today running the following story:

Double-decker trains could be introduced on some of the UK’s busiest railway lines under new proposals to ease overcrowding.

The trains are already used in other parts of Europe but have been ruled out in Britain in the past because of the low bridges and tunnels on UK lines. Designers are now working on proposals that would involve train compartments being lowered towards the tracks to create the height needed to accommodate two-deck carriages.

The interior of the carriage would be overhauled, with aisles on both decks positioned to the side rather than up the middle, to create extra space.

The project, led by the Swiss architect Andreas Vogler, is among three at an advanced stage as part of a £3.5 million project to improve conditions on British railways. Another involves a passenger train that can carry freight at off-peak periods.

The Rail Safety and Standards Board (RSSB), which is running the design competition, said that some of the new concepts could be introduced between 2020 and 2022 to “address the challenges facing the UK rail industry”.

The introduction of double-decker trains is being seen as an attempt to tackle overcrowding at peak times.

Recent figures from the Department for Transport showed that almost 250,000 commuters were being forced to stand on trains into major British cities each morning, with services running at 3.5 per cent overcapacity.

The 4.22am service from Glasgow to Manchester airport, which is run by TransPennine Express, is officially the busiest in the country, running at 186 per cent of capacity at its peak. A small number of double-decker trains were introduced between London and Kent in the 1950s but failed to catch on because of cramped conditions, poor ventilation on the upper deck and technical difficulties.

A demonstration model of the new design — dubbed the Aeroliner 3000 — will be built next year and presented at trade shows.

Trevor Bradbury, from the RSSB, said: “When you walk on to a train nowadays, you step up on to the carriage. There is actually a lot of space that you can use beneath the vehicle, which is what this design does.”

http://www.thetimes.co.uk/tto/business/industries/transport/article4614838.ece

 

[NSEFAN]

Designers are now working on proposals that would involve train compartments being lowered towards the tracks to create the height needed to accommodate two-deck carriages.

I guess this could work if you can shift the under-floor equipment somewhere else. The double-decker EMUs in France seem to use this principle.

Another involves a passenger train that can carry freight at off-peak periods.

This I am curious about. My understanding was that the only freight which makes any kind of money for the railway is bulk haulage and containers. This snippet sounds like parcels traffic, but it'd be interesting to see what's actually proposed there.

The introduction of double-decker trains is being seen as an attempt to tackle overcrowding at peak times.

It may help not help so much when the line capacity has decreased, due to the increased dwell time of a double decker train (unless you increase the number of platforms at key stations, which kind of defeats the point of a double decker train that wouldn't require infrastructure modifications).

 

[najaB]

I know there have been various threads about this before but The Times are today running the following story...

As has been pointed out many, many times before it isn't possible to build a double-deck passenger train that both fits in the the UK's loading gauge and has dwell times comparable to current single deck stock. Moving the aisle to the side can only make the dwell time worse.

 

[Tim R-T-C]

They have been suggested plenty of times before - they are not necessarily an advantage - double the number of people using each door means ingress and exit are slower. A frequent service with reliable trains is IMHO more important to easing rush hour woes.

They seem to be ignoring most of the recent design moves in British train development - ie. the London Overground and Underground stock with wide gangways and less seats to allow larger capacity and less crushing.

Service patterns need to change as well - that the busiest commuter service in the country is a long distance train shows the problem - these trains should be timetabled to appeal to long distance passengers so dedicated commuter trains can take the busy loadings.

I think the 'passenger train to carry freight' idea just sums up the level of discourse here. Because we have such a shortage of freight locomotives in this country and the best solution to rush hour issues, is to take the rolling stock away when it could be receiving maintenance and use it to carry "freight".

 

[telstarbox]

A double decker train would also have a much higher centre of gravity, so would it work with existing curves and line speeds?

 

[bangor-toad]

Hi there,
This project is one of the finalists in the design competition run by RSSB. Here's a link to the finalists that have got funding.

I don't think that the double deck proposal is actually for squeezing double deck high capacity, low dwell, trains as they just don't/can't work out. I think the study is more to look at the materials and designs that could be used in HS2 trains in the future.

The project that seems to make the most sense is the Horizon project that has adjustable seating. This lets there be a 2x2 layout for off peak that can convert on-demand to a higher density standing / perching layout for peak.


If you've got ideas keep looking as there's usually money about to develop them.
Cheers,
Mr Toad

 

[gordonthemoron]

the doors in the double decker pictured are surely too small for a double decker?

 

[jopsuk]

Sigh. Architect led projects for things that aren't buildings... So often terrible. Hell, even architect led projects for buildings often need serious doses of reality to be injected by structural engineers!

 

[100andthirty]

Having recently spent a week travelling on mainly double deck trains, I can attest to the terrible impact of them on dwell times. There are also lots of other issues.

1) UK has a more restrictive gauge than almost any other European country. This leads to huge problems accommodating the required height.
2) Lets assume that, 9 inches of clearance are needed under the lower deck, that the floors and the roof are each 2 inches thick and we allow for people who are 6 foot 4 inches tall (not unusual these days) this means the minimum height above rail of almost 14 feet
3) the maximum height in the gauge is at the centre of the vehicle.this effectively positions the top deck gangway. One of the comments in the press release suggests a gangway not on the centre line. This could be applied on the lower deck, but would require a step up to seats on the upper deck where headroom is already restricted even on continental gauge
4) the offest from the nearest rail to the platform is much smaller than the continental gauge allows, thus the lower deck would have to be much narrower even than the normal UK train. This is likely to be in the order of 12 inches narrower.
5) in order to avoid "wasting" loads of space on stairs up and down, most double deck trains are at least 26m long. UK would probably not be able to use longer than 20 to 23 m without further width reductions. Helps boading and alighting but doesn't give the capacity one might expect
6) France did use some 3 door per side doubel deck vehicles kn one of the RER lines. I do not know how or whether is helps dwell times, but further reduces the additional capacity that could be delivered.

 

[NSEFAN]

Sigh. Architect led projects for things that aren't buildings... So often terrible. Hell, even architect led projects for buildings often need serious doses of reality to be injected by structural engineers!

Isn't the rule that if a building has won an architectural award, that usually means that it will be a right pain in the backside for the day-to-day users of it?

 

[ac6000cw]

A double decker train would also have a much higher centre of gravity, so would it work with existing curves and line speeds?

Since they are common in other countries (including a lot of double-deck 'duplex' TGV sets in France) the answer has to be 'yes' really.

As others have said, in design terms they are both lower and higher - the lower saloon floor is normally just above rail level with the 'underfloor' equipment moved elsewhere. So the CoG isn't as high as you might think.

(In US/Canada they run both large double-deck passenger cars at 80mph+ and 20 feet high double-stacked container trains at 70mph).

 

[The Ham]

Sigh. Architect led projects for things that aren't buildings... So often terrible. Hell, even architect led projects for buildings often need serious doses of reality to be injected by structural engineers!

It has been suggested that most uses of the A******** word in engineering offices should result in payments to the swear pot.

 

[Bletchleyite]

A double decker train would also have a much higher centre of gravity

It probably wouldn't, because while it has some people sitting higher, it also has some people sitting lower. And the overall body can't be much higher.

 

[TrainBoy98]

Since they are common in other countries (including a lot of double-deck 'duplex' TGV sets in France) the answer has to be 'yes' really

Not necessarily, most routes that the Duplexes run on are highspeed lines, not classics.

 

[Bletchleyite]

I guess this could work if you can shift the under-floor equipment somewhere else. The double-decker EMUs in France seem to use this principle.

The problem is that below-platform width means that you'd be talking 2+1 (or 3+0) at best.
--- old post above --- --- new post below ---

Not necessarily, most routes that the Duplexes run on are highspeed lines, not classics.

All of Germany's double deckers run on classic lines, I believe up to 160km/h. Switzerland's run up to 200km/h I believe, though often on the pseudo-LGV.
--- old post above --- --- new post below ---

Service patterns need to change as well - that the busiest commuter service in the country is a long distance train shows the problem - these trains should be timetabled to appeal to long distance passengers so dedicated commuter trains can take the busy loadings.

The main problem with that train is that it is too short. We continue to prat about increasing frequencies with 4-car trains, yet we don't spend the money on rolling stock to solve it other than on Virgin West Coast.

If all TPE Manchester-Scotland services were 12x20m or 10x23m, there wouldn't be such a problem. Similarly, all XCs need to be that sort of length, as well as all South East commuter services that aren't already. No Northern services should be fewer than 3x23m, most should be 4x23m at least, and Manchester suburbans 8x20m. These are the kinds of length required - far longer than now.

A massive DMU (ideally bi-mode) and EMU building programme is required, urgently.

 

[AM9]

...
6) France did use some 3 door per side doubel deck vehicles kn one of the RER lines. I do not know how or whether is helps dwell times, but further reduces the additional capacity that could be delivered.

That doesn't seem like a clever idea unless the platform height is the same as the lower deck floor. ouble deck coaches only really work because the doors are positioned over the bogies where the floor has to be about 1m above rail height anyway. If the middle door is a lower deck level, then it would mean steps up to the platform and wasted space above to give sufficient headroom. If it is at normal height (for high density) platforms, there would need to be four flights of stairs to each deck, (one at each end and two by the centre doors). Such a design would be into the laws of diminishing returns.
Except on new lines with purpose designed infrastructure, there's little or no chance of double deck trains in the UK on the classic network. The best designs of single deck high capacity commuter trains with high frequency/minimum dwell times are the only real option for the future. Still, it giove the lay press a broken record to play on slow news days.

 

[The Ham]

The main problem with that train is that it is too short. We continue to prat about increasing frequencies with 4-car trains, yet we don't spend the money on rolling stock to solve it other than on Virgin West Coast.

If all TPE Manchester-Scotland services were 12x20m or 10x23m, there wouldn't be such a problem. Similarly, all XCs need to be that sort of length, as well as all South East commuter services that aren't already. No Northern services should be fewer than 3x23m, most should be 4x23m at least, and Manchester suburbans 8x20m. These are the kinds of length required - far longer than now.

A massive DMU (ideally bi-mode) and EMU building programme is required, urgently.

The problem in the South East is that many services (at least into or out of a London terminus) are already 12x20m or 10x23m with most of the rest are shorter due to platform length issues. Even where there are shorter services having the extra stock to run them as full length trains isn't going to make a lot of difference to the number of people having to stand.

Conversely, on the Non London services, although there is some overcrowding on some 3 and 4 coach trains having more than 6 coach trains would mostly probably be over provision (even in the peaks) for some time. Of course that's not to say that they shouldn't be lengthened and/or be more frequent.

I would argue that the TOC's will see a better return changing from 1tph to 2tph or from 2tph to 3tph than they would be lengthening the trains by the same number of coaches (3tph with 2 coaches is better for the TOC's than 2tph with 3 coaches). However there is a need for the TOC's to (as each franchise is relet) look at lengthening as many peak hour services as they can.

 

[DarloRich]

I know there have been various threads about this before but The Times are today running the following story:



http://www.thetimes.co.uk/tto/business/industries/transport/article4614838.ece

wibble. That is all

 

[RobShipway]

This idea has been tried before with double desk trains within the South East using https://en.wikipedia.org/wiki/SR_Class_4DD in the late 1940's, but these where not successful due to the cramp conditions.

 

[Bletchleyite]

The problem in the South East is that many services (at least into or out of a London terminus) are already 12x20m or 10x23m with most of the rest are shorter due to platform length issues. Even where there are shorter services having the extra stock to run them as full length trains isn't going to make a lot of difference to the number of people having to stand.

The South East does have platform length constraints that are in some cases not resolvable at reasonable cost. But often they are resolvable, and there are *still* overcrowded 4-car trains running around the place where 8 or even 12 would fit.

Conversely, on the Non London services, although there is some overcrowding on some 3 and 4 coach trains having more than 6 coach trains would mostly probably be over provision (even in the peaks) for some time.

I am strongly of the view that the present low quality, overcrowded service on TPE and Northern is causing a significant suppression of demand. Sort that out and more will come.

I would argue that the TOC's will see a better return changing from 1tph to 2tph or from 2tph to 3tph than they would be lengthening the trains by the same number of coaches (3tph with 2 coaches is better for the TOC's than 2tph with 3 coaches). However there is a need for the TOC's to (as each franchise is relet) look at lengthening as many peak hour services as they can.

TOCs get the most return by crush-loading short trains. It doesn't mean that is the right option.

To use the MKC-Clapham service as an example, I long took the view that you would fill 8 car at 1tph, or 8 car at 2 - increase the frequency and more passengers will come.

 

[furnessvale]

It probably wouldn't, because while it has some people sitting higher, it also has some people sitting lower. And the overall body can't be much higher.

Although I think the whole idea of double deck withing UK loading gauge is a nonsense, on this particular point wouldn't an engineer have to design for a "worst case" scenario of a fully loaded top deck with an empty bottom deck?

 

[edwin_m]

Although I think the whole idea of double deck withing UK loading gauge is a nonsense, on this particular point wouldn't an engineer have to design for a "worst case" scenario of a fully loaded top deck with an empty bottom deck?

A double deck coach would weigh at least 40 tonnes empty. 100 passengers crammed into the top deck would weigh about 8 tonnes, so it doesn't really make that much difference. In any case the speeds round curves are limited by passenger comfort and are way below those where there is any risk of overturning.

 

[Haydn1971]

Put simply, you lengthen and increase frequency* to the network ceiling, then you build a new line - why is this concept so difficult to understand.

* Increased frequency may mean losing the services that create the biggest routing headaches - keep it simple

 

[WatcherZero]

It would work in the UK as an outer suburban design, 3+0 or 2+1 on the top deck and large standing area with pull down longitudinal seating on the lower deck. Able to cope with the heavy loads of a city centre which then run on as quiet rural routes. It means you wouldnt have to run twice as many carriages to cope with the peak loads which are then completely empty and wasteful later in the journey. Most structural alterations required are usually inner city with much less structure modifications required in rural areas.

You can increase door width slightly and probably achieve a 40% higher crush capacity. Heck with no seats in the lower area you could add a central door (possibly 'exit only') to the lower deck with steps while keeping level access at the carriage ends and between carriages over the wheels.

 

[Bletchleyite]

If you make everything call at all stations (and possibly close smaller ones) your frequency can tend towards your station dwell time. Wouldn't be universally popular, though - 20tph Euston to MK might be nice, but an hour journey time?

 

[SpacePhoenix]

To have double decker trains in the UK the infrastructure would either have to be built from new to a much larger loading gauge or be rebuilt.

If the infrastructure did exist then the way the trains in Sydney Australia are would be the way to go. Both sides have a set of double doors at each end (sides), they're at platform level and have the disabled seating, probably loos as well. The main seating areas are in the middle going up a few steps or down a few steps

 

[mbreckers]

If double-decker trains were to be theoretically introduced, how high up would OHL be? Would it be too high for current stock to reach with a panto?

 

[D365]

If double-decker trains were to be theoretically introduced, how high up would OHL be? Would it be too high for current stock to reach with a panto?

Double-decker stock can't be introduced. It's really not that simple of a case.

 

[AngusH]

Has it ever been calculated how much it would cost and what would be involved to convert some section of the network to a full continental loading gauge?

I know loading gauges have been increased for larger freight containers, so the methodology must exist.

I'm just wondering if anyone has run the figures/done the relevant design costings for it.

 

[Peter Mugridge]

That doesn't seem like a clever idea unless the platform height is the same as the lower deck floor. Double deck coaches only really work because the doors are positioned over the bogies where the floor has to be about 1m above rail height anyway. If the middle door is a lower deck level, then it would mean steps up to the platform and wasted space above to give sufficient headroom. If it is at normal height (for high density) platforms, there would need to be four flights of stairs to each deck, (one at each end and two by the centre doors). Such a design would be into the laws of diminishing returns.

That's exactly what the triple-doored French double deck units do - the floor is raised in the middle of the carriage where the mid door is so it's at the same height as the bits at the end.

The stock in question is the MI2N / MI09 / Z22500 classes. They are extremely claustrophobic and cluttered inside with little seating capacity. The trailers seat just over 100 people each.

By far the best of the French double deckers are the earlier twin doored Z20500 class; very spacious and very neatly laid out inside. The trailers on these can seat up to 204 each.