For help, advice and discussion about stuff not related to aviation. Play nice: no religion, no politics and no axe grinding please.
By chevvron
#1912743
Apologies if there is already a thread but I haven't found one.
Crossrail (The Elizabeth Line) finally started revenue earning journeys on 24 May 2022 but is still not complete and one of the 'driving' reasons for it is to provide extra capacity.
If so, I was wondering why instead of just running longer trains (12 carriages I believe) why not use double deck carriages instead?
The RER service which runs underground for some of its route along the south side of the Seine in Paris has been using double deck trains for years , in fact the Southern Railway, which became BR Southern Region after nationalistion in 1948 also used double deck trains but after nationalisation, these routes ceased operations and reverted to single deck trains instead, thus leading to a reduction in carrying capacity.
We've all seen the cavernous tunnels which have been dug under London for Crossrail, so why was the use of double deck trains not considered to provide extra 'growth' when 12 carriage trains become overloaded?
In the Netherlands, double deck trains have been used overground for many years too and a couple of years ago, Michael Portillo in his TV series highlighted the way double deck trains could be used across the USA.
So why did the planners not figure this out?
User avatar
By rikur_
FLYER Club Member  FLYER Club Member
#1912746
Double decker trains are generally not considered efficient for commuter operations due to the increased boarding and alighting times. They're really a 'cheap and dirty' retrofit on existing networks that have run out of platform capacity, they would be an odd choice for a new build in most circumstances.

The relatively tight loading gauge of GB railways (below 4m on most lines, compared to 4.5m in mainland Europe) makes double deckers a snug fit on most of the conventional network (remember that crossrail runs on legacy network either side of the tunnel). Yes, it's possible, but in a cramped fashion.

Generally, building longer platforms is cheaper than building wider bore tunnels along the whole network. (Noting Crossrail has to weave between other tunnels in places so lateral space was also a constraint).

In many ways the experiment on the Southern that you referred to proved most of the short comings, hence why it never went beyond the initial two trains built.
User avatar
By kanga
#1912942
CloudHound wrote:Southern also ran a carriage converted to an Olde English Pub complete with bar stools and fake beams. :lol:


.. this immediately made me think of The Titfield Thunderbolt :) :

https://en.wikipedia.org/wiki/The_Titfield_Thunderbolt

.. one of the finest Ealing Comedies :thumright:

Other thoughts on this thread, and Crossrail generally:

a. Sydney (NSW) Metro also uses double-deck carriages, with steps up and down connecting 'mezzanine' boarding area carriage ends with seating areas

b. I noted that on day of opening, BBC News UK site had quite a few articles, and England site was full of articles, on Crossrail, historic and current. ISTR hearing recently that ?56% of central UK government expenditure on public transport (operations and infrastructure) is in London or its suburbs, ie even before expenditure on HS2. Overspends on Crossrail seemed regularly to be 'nodded through' by Treasury while lesser one-time sums which would have paid for the electrification of the South Wales railway mainline were cancelled as 'unaffordable'. And, of course, the plans for Northern sections of HS2 have recently been significantly downgraded. Perhaps it is unsurprising that may North and West of London are reported to feel fiscally and thence politically 'neglected'.

[this is, obviously, not to decry the engineering achievements involved in Crossrail and in HS2]
townleyc liked this
User avatar
By Paul_Sengupta
FLYER Club Member  FLYER Club Member
#1912954
I can see an issue with double decker trains in that, as Kanga says, you get on in the middle then take the steps either up or down. Step free access is now a big thing on the underground and is becoming so on overground lines as well. Double deckers aren't well suited to that.

As for infrastructure investment, I can see that not giving extra money to Crossrail means the whole thing grinds to a halt, wasting the billions spent so far. Electrifying Cardiff to Swansea or not has very little effect on anything other than giving a nod to green credentials.
User avatar
By rikur_
FLYER Club Member  FLYER Club Member
#1912969
kanga wrote:b. I noted that on day of opening, BBC News UK site had quite a few articles, and England site was full of articles, on Crossrail, historic and current. ISTR hearing recently that ?56% of central UK government expenditure on public transport (operations and infrastructure) is in London or its suburbs, ie even before expenditure on HS2. Overspends on Crossrail seemed regularly to be 'nodded through' by Treasury while lesser one-time sums which would have paid for the electrification of the South Wales railway mainline were cancelled as 'unaffordable'. And, of course, the plans for Northern sections of HS2 have recently been significantly downgraded. Perhaps it is unsurprising that may North and West of London are reported to feel fiscally and thence politically 'neglected'.


Part of it is a structural flaw in how the 'Green Book' used for HMT business cases attributes economic value, in that it makes it easier to generate more value from areas that already have high economic value, than to generate new value in new areas. It's something that Sunak recognised very early in his tenure, and is supposed to be getting updated.
Flyin'Dutch', kanga liked this
User avatar
By kanga
#1912978
Paul_Sengupta wrote:... Electrifying Cardiff to Swansea or not has very little effect on anything other than giving a nod to green credentials.


Reducing congestion and delay on Western end of M4 ? Genuine (not merely 'nodded') 'green' credentials, and economic benefits along both the newly electrified bit and all the way to Paddington ? If the arument is sound hor HS2 then is it not also partly sound for that programme ?
Flyin'Dutch' liked this
User avatar
By Paul_Sengupta
FLYER Club Member  FLYER Club Member
#1912990
kanga wrote:Reducing congestion and delay on Western end of M4 ?


How so? The trains run whether they run on electricity or diesel/chip fat.

kanga wrote:Genuine (not merely 'nodded') 'green' credentials, and economic benefits along both the newly electrified bit and all the way to Paddington ? If the arument is sound hor HS2 then is it not also partly sound for that programme ?


The trains don't run any faster (they all have a max of 125mph on the line currently) or differently, they just use a different form of energy to do so. The old diesel 125s have been tested up to something like 149mph. I'm not sure how it relates to the HS2 argument, the reasoning for that is to have another track to increase north-south capacity, which might as well be fairly straight, be electric powered and have in-cab signaling to allow speeds of over 125mph.
rikur_ liked this
User avatar
By rikur_
FLYER Club Member  FLYER Club Member
#1913015
it's interesting to see Transport for Wales' "discontinuous electrification" of the valley lines. Basically they are electrifying the bits that are easiest to electrify, missing out difficult tunnels, viaducts, etc and missing out a couple of lines entirely. Some trains will have battery packs, and some will have battery packs and generators depending on the level of overhead line coverage. I suspect we'll see a lot more of this, and then probably hydrogen for heavy freight services that need to run to remote quarries etc where it will never be economic to put in overhead electrics.
User avatar
By Paul_Sengupta
FLYER Club Member  FLYER Club Member
#1913022
Seems like the Valley Lines would be a good candidate for third rail electrification, like South West Railways. Or maybe it's too wet and flooded for that...
User avatar
By rikur_
FLYER Club Member  FLYER Club Member
#1913028
Paul_Sengupta wrote:Seems like the Valley Lines would be a good candidate for third rail electrification, like South West Railways. Or maybe it's too wet and flooded for that...

safety regulations have effectively banned any new third rail electric schemes for some time now, albeit the case continues to be lobbied for tactical extensions such as Uckfield. Third rail isn't very green either, with more electricity lost in transmission losses than delivered to traction. The valleys are well down the route of discontinuous overhead lines now.
Flyin'Dutch' liked this
User avatar
By Flying_john
FLYER Club Member  FLYER Club Member
#1913047
rikur_ wrote:it's interesting to see Transport for Wales' "discontinuous electrification" of the valley lines. Basically they are electrifying the bits that are easiest to electrify, missing out difficult tunnels, viaducts, etc and missing out a couple of lines entirely. Some trains will have battery packs, and some will have battery packs and generators depending on the level of overhead line coverage. I suspect we'll see a lot more of this, and then probably hydrogen for heavy freight services that need to run to remote quarries etc where it will never be economic to put in overhead electrics.



I would have thought this is an ideal opportunity for investment in using Welsh Coal and bringing back good old steam trains.

:mrgreen: :mrgreen: :lol: :lol:
chevvron liked this
By chevvron
#1913057
Paul_Sengupta wrote:I can see an issue with double decker trains in that, as Kanga says, you get on in the middle then take the steps either up or down. Step free access is now a big thing on the underground and is becoming so on overground lines as well. Double deckers aren't well suited to that.


In my experience, (Paris RER and Amsterdam main line) passengers board at each end not the middle and go up or down a few steps.
Watching Portillo on telly, Amtrak do the same.
User avatar
By rikur_
FLYER Club Member  FLYER Club Member
#1913065
chevvron wrote:
In my experience, (Paris RER and Amsterdam main line) passengers board at each end not the middle and go up or down a few steps.
Watching Portillo on telly, Amtrak do the same.

Correct (albeit I think @Paul_Sengupta meant 'middle' vertically). The doors are normally over the bogies, and then you have a the double decker section between the bogies, with steps up/down to the two decks. The lower deck being lower than the top of the bogies, in a similar manner to how shipping containers sit on freight wagons.
kanga liked this
User avatar
By Paul_Sengupta
FLYER Club Member  FLYER Club Member
#1913088
Yes, vertically, you get on then go up or down steps.

Flying_john wrote:I would have thought this is an ideal opportunity for investment in using Welsh Coal and bringing back good old steam trains


Funny you should say that, I was on a heritage steam railway recently and asked them about the coal as it looked a bit brown. They said yes, they used to get really good quality steam coal from the opencast near where I'm from, but since that shut down (probably for green reasons) they've had to buy foreign coal which is apparently inefficient and dirty and not very nice to work with.