Length of units vs Cascades

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Peter Sarf

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I get the impression that any cascade of stock away from London and the SE has a common problem. Most stock is 4-car but often needs to be 3-car outside London.

However the 508s lost a trailer when they left BR-SW division and went to Merseyside. I suppose 315s reduced to 3-car would have better acceleration and that might actually be a benefit up the Welsh valleys as I assume thay are not as flat as London ?. It does seem a waste of coaches though. I can see the 313s going out of London as, on Southern, they could be replaced by some more electrostars.

What about the new Thameslink trains. I seem to remember they are to be formed from long units 5-8 cars ?. What use will they be in the future when they get cascaded away ?.
 
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ukrob

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508s had a carriage removed for operational reasons and to match the 507s.

Why does cascaded stock 'need' to be three car?

I doubt new Thameslink stock will ever be cascaded. It is bespoke stock.
 

Peter Sarf

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Under what circumstances would they ever get cascaded away though?
The same circumstances that mean 319s are getting cascaded away now. I know that in the past a lot of London and SE stock remained in the area until withdrawl but some does get re-used. Thameslink is a large fleet and some of it will inevitably one day be cascaded away I suspect.
 

ukrob

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The same circumstances that mean 319s are getting cascaded away now. I know that in the past a lot of London and SE stock remained in the area until withdrawl but some does get re-used. Thameslink is a large fleet and some of it will inevitably one day be cascaded away I suspect.
As I said, it is bespoke stock. It won't be.
 

Peter Sarf

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Why does cascaded stock 'need' to be three car?

I doubt new Thameslink stock will ever be cascaded. It is bespoke stock.
I have noticed comments on the forum about platforms being multiples of three cars in length. Seen these in threads about South Wales electrification, Birmingham Cross City& NW electrificaton. Which is what prompted me to start this thread.

Is making Thameslink stock bespoke a good idea, I know its a question deserving of a thread of its own. But my point is will this fact come back to haunt the railways one day ?.
 
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sprinterguy

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As I said, it is bespoke stock. It won't be.
The 319s were essentially bespoke stock for the original Thameslink opening as well though, even if they weren't as specialised as the new Thameslink Desiro Citys' are going to be and shared a common bodyshell and some components with other EMUs of the time. It is this commonality that has allowed them to be cascaded elsewhere well within their lifetime, when the passage of over 20 years has proved them to be insufficient to meet the capacity demands of present day and future Thameslink. Surely the same scenario could befall the new Thameslink units in, say, 2042?
 

WatcherZero

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Well generally most DMU classes are two or three car length and most EMU classes are 4 car length. DMU you could easily therefore form formations of 2,3,5,6 car length while EMU you can only form 4,8 car formations. Most platforms at smaller regional stations are 4 car length and 6 car at the larger regional stations (while the major stations could accomadate trains as long as Pendolino lengths) so naturally if you wanted to use a couple pair of EMU's lengthening would be required. Theres no suggestion this wont happen though
 

Peter Sarf

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The 319s were essentially bespoke stock for the original Thameslink opening as well though, even if they weren't as specialised as the new Thameslink Desiro Citys' are going to be and shared a common bodyshell and some components with other EMUs of the time. It is this commonality that has allowed them to be cascaded elsewhere well within their lifetime, when the passage of over 20 years has proved them to be insufficient to meet the capacity demands of present day and future Thameslink. Surely the same scenario could befall the new Thameslink units in, say, 2042?
Yes, well put, thats the sort of thing that I mean.

Putting it like that thirty years is plenty of time for things to change. I know we should not get tied up by loads of potential maybe's when doing planning/design but how necessary was it for the new Thameslink stock to be so bespoke ?.

On the other hand in thirty years time a lot of the rest of the network might be exactly the same flavour of bespoke :oops:. How likely ?.
 

aformeruser

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Well generally most DMU classes are two or three car length and most EMU classes are 4 car length. DMU you could easily therefore form formations of 2,3,5,6 car length while EMU you can only form 4,8 car formations.
Yes and the 319s have 20m carriages not 23m carriages, so a 4 car 319 is shorter than a 156+156 or 150+156 combination. I imagine the 319s will be fitted with a complaint toilet and have adequate wheelchair space available meaning some North West services could see a reduction in capacity as a result of cascaded units after electrification or we could see 6 car DMU combinations running fully electrified services.
 

hwl

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Well generally most DMU classes are two or three car length and most EMU classes are 4 car length. DMU you could easily therefore form formations of 2,3,5,6 car length while EMU you can only form 4,8 car formations. Most platforms at smaller regional stations are 4 car length and 6 car at the larger regional stations (while the major stations could accomadate trains as long as Pendolino lengths) so naturally if you wanted to use a couple pair of EMU's lengthening would be required. Theres no suggestion this wont happen though
Exactly. If the Skipton line experience is repeated on the future electrified lines, the 4th coach will be need to take the extra passengers that electrification should bring. Besides with extra line closures for some of the electrification work on the branches where the HOOP train may not reach, platform lengthening might be easier than if not combined with electrification.
anything being electrified should probably be lengthened to take 8x23m as a minimum if possible for future proofing.
 

aformeruser

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If the Skipton line experience is repeated on the future electrified lines, the 4th coach will be need to take the extra passengers that electrification should bring.
Electrification bringing extra passengers? More likely better service frequency and newer trains attracting the extra passengers. Some Sunday services have seen exponential growth when a Pacer/Sprinter service has become more frequent.

anything being electrified should probably be lengthened to take 8x23m as a minimum if possible for future proofing.
What about where that is not possible e.g. at Liverpool South Parkway you can't build an 8 car platform unless you knock down the dual carriageway bridge which takes the B5171 over the track.
 

Peter Sarf

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The hope would be that electrification would bring the increase in demand that justifies longer platforms. I just wonder if it will instead stall some electrification proposals. Perhaps in those cases a 3-car electric unit (e.g. 315s) could get converted back to 4-car a few years after electrification when/if the demand has increased enough to make the need for longer platforms undeniable.

Would not be so possible if an 8-car Thameslink unit needed to be temporarily 3-car !.
 

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Electrification bringing extra passengers? More likely better service frequency and newer trains attracting the extra passengers. Some Sunday services have seen exponential growth when a Pacer/Sprinter service has become more frequent
I agree - a lot of people talk about the "sparks effect" as being this magical reason why people prefer EMUs to DMUs (as if most members of the public really notice the fuel).

The reality is that an upgraded timetable with longer trains (which is what happened on the Ilkley/Skipton lines, and will no doubt happen on the Valley lines etc) will see more passengers.

Give people a more reliable service with more chance of getting a seat and they are more likely to use the train, regardless of electrification.

For me, electrification is more of a "means to an end" (as there's low chances of new DMUs being built, electrifying lines is the easiest way to ensure that these routes get longer stock/ more services).
 

aformeruser

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Would not be so possible if an 8-car Thameslink unit needed to be temporarily 3-car !.
Apparently the 319s would need to be completely rewired if the formations are changed. We'll take the FCC 377s reformed in to 3 car formations though (leaving extra centre cars for Southern) with the option for a future order for additional 377s and centre cars :D
 

tbtc

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The hope would be that electrification would bring the increase in demand that justifies longer platforms. I just wonder if it will instead stall some electrification proposals. Perhaps in those cases a 3-car electric unit (e.g. 315s) could get converted back to 4-car a few years after electrification when/if the demand has increased enough to make the need for longer platforms undeniable
This is what happened at Ilkley/ Skipton - the Pacers were replaced by three coach 308s (with the fourth coach removed before they left London) which were then replaced by three coach 333s (once passenger numbers justified investment) which were then lengthened to four coaches as passenger numbers continued to grow, with Monday's announcement suggesting even longer trains in the future.

I'm going to get bored reading of complaints about "cast off three coach London EMUs replacing more modern DMUs" in parts of the country - simple truth is that on most lines a three coach 315 would be better than the two coach Pacer/Sprinters that currently run on them. Once the 315s have been running for a couple of years then it'll be easier to justify newer/longer trains.
 

Peter Sarf

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This is what happened at Ilkley/ Skipton - the Pacers were replaced by three coach 308s (with the fourth coach removed before they left London) which were then replaced by three coach 333s (once passenger numbers justified investment) which were then lengthened to four coaches as passenger numbers continued to grow, with Monday's announcement suggesting even longer trains in the future.

I'm going to get bored reading of complaints about "cast off three coach London EMUs replacing more modern DMUs" in parts of the country - simple truth is that on most lines a three coach 315 would be better than the two coach Pacer/Sprinters that currently run on them. Once the 315s have been running for a couple of years then it'll be easier to justify newer/longer trains.
Yes I have been waiting for the "we dont want Londons cast offs" cry. The 308s were an example of Ex-London stock being used to make electrification more likely. Then the new/longer units get paid for later. Anything that makes electrification more likely is good. Newer units can come along later. That is what the 315s and other PEP family units are good for ?.
 

aformeruser

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Yes I have been waiting for the "we dont want Londons cast offs" cry. The 308s were an example of Ex-London stock being used to make electrification more likely. Then the new/longer units get paid for later. Anything that makes electrification more likely is good. Newer units can come along later. That is what the 315s are good for.
The difference is 3 car 308s replaced 2 car DMUs in Yorkshire. The North West and Valley Lines already have 4 car operation on peak services so 5 or 6 car EMU operation will be required to have the same effect.

What effect replacing a 6 car DMU between Manchester and Preston via Bolton with a 4 car operation via Bolton and a 4 car operation via Wigan will have is unknown.
 

Peter Sarf

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The difference is 3 car 308s replaced 2 car DMUs in Yorkshire. The North West and Valley Lines already have 4 car operation on peak services so 5 or 6 car EMU operation will be required to have the same effect.

The result of replacing a 6 car DMU between Manchester and Preston via Bolton with a 4 car one via Bolton and a 4 car one via Wigan will have is unknown.
So would platforms need lengthening to 6 cars (some in wales already are iirc) ?. Or would you go for the full 8-cars from day one ?. Or we wait and see about the re-shaping of services you mention in the NW - that might upset the locals !.

Re the "Sparks Effect" (that was first mentioned in as far back as the WCML electrification ?). I know electrification gives better acceleration thus increasing line capacity. The other gains of longer more frequent trains might be for the reason of latent demand that ALSO happened to justify electrification. What seems to be undeniable is that electrification is associated with improved service frequency and capacity (I am not saying which causes which !).
 
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aformeruser

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So would platforms need lengthening to 6 cars (some in wales already are iirc) ?. Or would you go for 8-cars from day one ?.
Well that's the point. The 319s are supposed to stretch to cover the newly electrified North West routes and the Thames Valley routes. That will pretty much mean doubled up 319s are out of the question in both areas as there won't be enough. The only 319 option would be rewiring the units and reforming them in to 3 and 5 car formation with the 5 car formations being used on peak flows and 3 car formations on counter-peak flows. However, there would certainly be instances where a 3 car finishes up on a very busy service and a 5 car finishes up on a quiet service.
 

Peter Sarf

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Then I would throw some shortened 315s in to the equation then. I suspect they are not quite as speedy as 319s though ?. Perhaps 315s on inner suberban services taking pressure off 319 operated services. I am visualizing the NW services here.

Occurs to me someone needs to crack on with ordering something quick to design & build so as to replace SOME 315s & 319s before Thameslink and Crossrail units arrive. I know a place in Derby that could proably do it. They would be compatible, from a maintenance/knowledge angle, with what already works in the same areas as 319s and 315s currently work ;).
 

hwl

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Apparently the 319s would need to be completely rewired if the formations are changed. We'll take the FCC 377s reformed in to 3 car formations though (leaving extra centre cars for Southern) with the option for a future order for additional 377s and centre cars :D
Except they aren't FCC's they are leased to Southern and are subleased by southern to FCC and will be heading back to southern at some point (replacing 313 etc on the east and west coastway routes which will then be life expired when the new TL stock arrives...).
 

aformeruser

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Except they aren't FCC's they are leased to Southern and are subleased by southern to FCC and will be heading back to southern at some point (replacing 313 etc on the east and west coastway routes which will then be life expired when the new TL stock arrives...).
By the time the 377s are released from Thameslink, the Southern franchise will have ended and any leasing agreement will have ended. Remember the National Express East Coast leased class 180s were never used on East Coast franchised services.

Southern are getting 130 new 377 carriages and the South London line is going over to LO and getting new 378s. This means, not only will Southern have the extra 377s that they would have got had Thameslink run to schedule but they would have many units surplus to requirements. Consequently, they will have to give up their 456 fleet which will go to SWT for extra capacity.

Southern have 57 class 313 carriages and FCC have 108 class 377 carriages, so the future franchise operator will need to prove they need 51 additional carriages in addition to the 313s being replaced if they are to get all the 377s currently with FCC.
 

hairyhandedfool

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Yes and the 319s have 20m carriages not 23m carriages, so a 4 car 319 is shorter than a 156+156 or 150+156 combination. I imagine the 319s will be fitted with a complaint toilet and have adequate wheelchair space available meaning some North West services could see a reduction in capacity as a result of cascaded units after electrification or we could see 6 car DMU combinations running fully electrified services.
I believe there are to be twice as many services for most of the day on the Chat Moss, with some all shacks services going to Piccadilly (and beyond) and others to Victoria (and beyond). Furthermore, I believe a 156 has a seated capacity around 150, whereas a 319/0 has a seated capacity of around 319.

....The only 319 option would be rewiring the units and reforming them in to 3 and 5 car formation with the 5 car formations being used on peak flows and 3 car formations on counter-peak flows....
It's not just rewiring though, a 3 car 319 would have no toilet (either that or the three car doesn't have a pan or traction motors), not to mention that the important equipment the ATS carries (not just the under-floor stuff) would have to find a new home on the three car units.
 

aformeruser

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I believe there are to be twice as many services for most of the day on the Chat Moss, with some all shacks services going to Piccadilly (and beyond) and others to Victoria (and beyond). Furthermore, I believe a 156 has a seated capacity around 150, whereas a 319/0 has a seated capacity of around 319.
The 319s were supposed to undergo a full mid-life refurbishment before entering service in the North West. This would include full DDA compliance and likely 2+2 seating* and would make the 319s more like the lower capacity 317/7s.

* 3+2 seating seems to be phased out following the high volume of complaints with the LM 350/2s and the SWT Desiros.

Occurs to me someone needs to crack on with ordering something quick to design & build so as to replace SOME 315s & 319s before Thameslink and Crossrail units arrive.
And where would those units go when the 319s and 315s are replaced by the Thameslink and Crossrail orders? Let me think - maybe replacing the 315s that have been cascaded elsewhere? In which case why not order new units for elsewhere to start with, instead of ordering new units with a spec to match lines they'll only spend a few years on?

By the way the North West lacks station toilets at many interchange stations and the service frequency won't be something like very 10 minutes, so they'll need to be a lot of investment in station toilets if you're planning on sending toilet-less trains up here.
 

hwl

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By the time the 377s are released from Thameslink, the Southern franchise will have ended and any leasing agreement will have ended. Remember the National Express East Coast leased class 180s were never used on East Coast franchised services.

Southern are getting 130 new 377 carriages and the South London line is going over to LO and getting new 378s. This means, not only will Southern have the extra 377s that they would have got had Thameslink run to schedule but they would have many units surplus to requirements. Consequently, they will have to give up their 456 fleet which will go to SWT for extra capacity.

Southern have 57 class 313 carriages and FCC have 108 class 377 carriages, so the future franchise operator will need to prove they need 51 additional carriages in addition to the 313s being replaced if they are to get all the 377s currently with FCC.
Also southern are leasing the 24x 5 car (=120 car) 442s that have 45 year old electrical equipment and are non DDA compliant (2019 and all that) that will need replacing at some point so that is 120 + 57 = 177 that need replacing above franchise commitments to increase capacity (10 car suburban). 177 + 48 (24 x 456s to SWT) = 225 to replace before additions and the total of new 5 car 377s and those coming back from TL is 238 - a net increase of 13 carriages to increase capacity (and those are effectively 5 carriages in the middle of a unit).
 

aformeruser

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Also southern are leasing the 24x 5 car (=120 car) 442s that have 45 year old electrical equipment and are non DDA compliant (2019 and all that) that will need replacing at some point
No less complaint than the 156s. In fact cheaper to make the 442s complaint than the 156s due to the longer train length.

I don't know what having refurbished electrical equipment rather than new has to do with it. Can't it be replaced like with the ex-LU stock on the Isle of Wight?
 

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The difference is 3 car 308s replaced 2 car DMUs in Yorkshire. The North West and Valley Lines already have 4 car operation on peak services so 5 or 6 car EMU operation will be required to have the same effect.

What effect replacing a 6 car DMU between Manchester and Preston via Bolton with a 4 car operation via Bolton and a 4 car operation via Wigan will have is unknown.
Note though that even just a 3-carriage class 315 is the same length, and probably offers slightly greater capacity, as a pair of Pacers, which are most frequently used on doubled up formations on the Valley Lines and often appear in the North West too. Leave the 315s as 4-car units and it means that you have the equivalent capacity of the longest formation used on the Valley lines (A pair of 150s) on every train, rather than just on a select few services.

That is likely to have a big effect on smoothing out the peak demand profile, rather than squeezing as many passengers onto a 2-car unit, and then leaving people behind who couldn’t get on to add to the numbers waiting for the following 4-car unit, rather than the 4-car train only catering for those passengers who have turned up after the preceding train departed.
 

Peter Sarf

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And where would those units go when the 319s and 315s are replaced by the Thameslink and Crossrail orders? Let me think - maybe replacing the 315s that have been cascaded elsewhere? In which case why not order new units for elsewhere to start with, instead of ordering new units with a spec to match lines they'll only spend a few years on?

By the way the North West lacks station toilets at many interchange stations and the service frequency won't be something like very 10 minutes, so they'll need to be a lot of investment in station toilets if you're planning on sending toilet-less trains up here.
I was thinking a follow on order of 377s for Southern was more likely to go QUICKLY to Derby. But yes I wonder how likely a surplus of electric units is later. Basically the supply of electric stock is a bit screwed up in the short term without the order. Long term I suspect there might not be as much surplus stock as currently looks possible.

As far as loos go. Dont forget there are less loos than should be expected in the South East as well. I dont know for sure but there are probably very few stations providing loos on the routes 315s work, certainly none at the stations I have used except Liverpool Street. I do know that I failed to find a loo on a journey from Gospel Oak to West Croydon last year and that is served by brand new toilet-less 378 trains. Its over an our with one change. At Highbury and Islington the local pub was suggested !. At Dalston (pre the connection opening) I found a superloo outside which took my money only, so I looked for an alley. At West Croydon - I asked and was told no loo.

I would say the advantage of 315s is that they are DDA compliant as they have no loos !.
 

John55

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Electrification bringing extra passengers? More likely better service frequency and newer trains attracting the extra passengers. Some Sunday services have seen exponential growth when a Pacer/Sprinter service has become more frequent.


What about where that is not possible e.g. at Liverpool South Parkway you can't build an 8 car platform unless you knock down the dual carriageway bridge which takes the B5171 over the track.
I think you mean the bridge that carries the railway over Woolton Road (B5171). Given the current state of Blackfriars station I don't think carrying the platforms over the bridge at Liverpool South Parkway (or extending 3 & 4 southwards) would be impossible if there was the demand to justify spending the money. East Midlands stop 7 car trains there 6 times per year with SDO!
 
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