Great Western Coffee Shop

I know this subject has come up, in sorts, in other posts - but when the Paddington - Oxford - Bristol - Cardiff routes get electrified what happens with with the Worcester/Hereford and Gloucester/Cheltenham routes, and indeed with other important routes such as Exeter/Plymouth/Penzance and Cardiff/Swansea?

I know there's all the talk about bi-mode trains but, call me old-fashioned, seems a hugely expensive/clumsy way to go about things. Seems to me:

1. Oxford/Worcester/Hereford and Swindon/Gloucester/Cheltenham and others become "Turbotised" or "Adelante-cised" - latter not necessarily so bad if the reliability were fixed except the need to change trains which I think would be totally retrograde;

2. There's a lot of diesels running under the wires as happens on the ECML and WCML - silly really; or

3. Extend the wires - and (forgive me) redouble the whole of the Cotswold line and Worcester/Hereford - makes sense in the long term and might have economic benefits.

OK, I'm no engineer but comments/ideas

Cotswold line will not meet the requirements of a business case required by the ORR.  The route North of Oxford to Birmingham / Coventry and or routes to Plymouth would be higher on the list of routes in the GW area.

I suggested making the Cotswolds line (Oxford to Worcester/Hereford) Turbos to Oxford (or possibly Reading) on here once, and it didn't go down well. Bi-mode trains (or Adelantes under the wires between Paddington and Oxford) probablly really are the only option for that route (although perhaps a few busy services, where 5-car is not sufficent, could retain life-extended IC125s until their 2035 deadline). In my opinion though, even if you go for bi-mode rather than Adelante operation, that doesn't mean a new order of bi-modes is necessary. A cascade of Voyagers from Virgin, by suppling them with more Pendolinos, and pantograph cars for the whole Voyager fleet, might just do it. Swansea is more complicated, if it were electrified a fair amount of the stock would probablly have to be bi-mode anyway because of the weekly diversion when the Severn Tunnel is closed. That means Cheltenham to Swindon and Severn Tunnel Junction would likely also need electrifing. Everything from Paddington to beyond Taunton, in my opinion, remain in the hands of Intercity 125s, so if Swansea and Cheltenham are wired I think that leaves Weston-Super-Mare as the only route I haven't thought up an alternative to IEP bi-mode for yet.

We have seen loco hauled sets with a dvt at the other end .... can we not have a diesel loco at one end and an electric loco that can act as a dvt at the other end so that under the wires its electric and west of england its diesel.... this gives the benifits of adding/removing capacity and quiet comfortable running with no engines underneath.... building a none engined carriage would cost alot less than one for a dmu or emu, there are other benifits.... if a dmu fails thats it service canceled, if a loco fails (subject to another being nearby) the service can be saved ..... im not saying this would work for local services and branch lines where dmu's are without doubt the best option

also.... and i do hesitate to put this but i dont want to start a new topic.... i really think xc should go back to loco hauled with the voyagers being split between swt for the west of england line and fgw for cardiff pompy, freeing up the 159's for fgw and northern to try and get rid of the pacers or at least have the pacers restricted to branch lines

Far too sensible an option especialy as Bombardiar are coming upi with the ideal diesel loco the TRAXX ME. ME standing for multi engine 4 automotive caterpillar engine which switch in out as power is required. Ideal for the Cotswold line trains. Farst push by electric loco to Oxford you'd need a DVT then pull by TRAXX ME to Wocester, lots of stops and uphill and down dale so full power is not needed for a lot of the journey. just like the Bournmouth Weymouth service after 67.

I also agree about just using a diesel locomotive when the wires end rather than go for bi-mode. I think there are a few people in the industry who will agree.
.
Pity they wont just order the full electric sets for the east coast mainline then transfer some of the class 91 & mk4 sets to work the London - Swansea services

Does anyone know why the Inverness and ABerdeen out of Kings Cross are HSTs rather than 91 to Edinburgh and diesel from there. Presumably there weren't enough Mark 4 sets to lose a couple for many hours and there were HST sets going spare after electrification

They used to have a novel solution on the Weymouth line. Extra-powerful 4-car EMU pushes another 8 unpowered "multiple units" with cab ends to the end of the electric. The train is then split leaving the EMU behind whilst the 8 un-powered cars are pulled to Weymouth by a diesel loco. Reverse in the opposite direction. Apparently this worked well.

Also Virgin used to pull pendelinos to Hollyhead using diesel locos. I went on one once, it was very slow.

Perhaps there is a need for a more potent diesel unit to pull all these EMUs around once they're out from under the wires. Deltic anyone?

i would think something like a class 70 or probably even a class 66/67 could do the diesel end..... and then you would just need a electric loco that could also work as a dvt .... and under the wires if the diesel is up front if its possible to use the diesel as a dvt in some kind of low power mode?

The Cotswold Line will not be wired until the XC route from Birmingham to Bristol and the Birmingham Snow Hill-Worcester services are electrified. Given that the Snow Hill services are about to get a brand-new dmu fleet and XC wiring is some way down the queue of future prospects, don't hold your breath.

Rhydgaled, just send a letter to the DfT telling them where they are going wrong and spare us yet another rendition of your theories.


They tried that with one of the many previous incarnations of the IEP design, then had to admit that you simply couldn't get enough traction power out of the diesel end to shift a full-length train.


Eh? Lots of stops and full power is not needed for a lot of the journey? What do you think an HST is using after all those stops to get back up to line speed? And apart from odd short bits of level track the line is a continuous climb from Wolvercot to north of Moreton-in-Marsh for westbound trains and a roller-coaster through the Vale of Evesham for eastbound services before you hit Campden bank. The route is hard work for diesels - illustrated by the ill-starred period of Class 31 operation in the 1970s. They simply weren't up to it - too heavy and not enough power.



Because BR realised that constantly coupling and uncoupling locos from sets of coaches led to lots of problems with the time division multiplex connections needed to drive the locos from driving van trailers. Keep locos and rolling stock semi-permanently coupled (also done on the WCML pre-Pendolinos) and you pretty much eliminate the problem. In any case, I don't think it was ever intended that the Mk4s would work with diesel traction off the core ECML route. The idea was the 91 could be uncoupled from them and used at night on freight and parcels, hence the blunt-end driving cabs.


It's Holyhead and Pendolinos. And Virgin still do, every Saturday. The speed has as much to do with the prevailing limits on the North Wales coast line as the locos used. It is not a racetrack.


Purpose-designed heavy freight locos or a track-bashing Bo-Bo intended for long-distance high-speed parcels work. Just the ticket for stops and starts every eight minutes. Not.

its not every eight mins is it tho.... and i said something 'like'

And importantly, you don't need to have the traditional loco/dvt arrangement to achieve the user requirement of quite carriages.  It's sufficient to have distributed traction (motors) powered an engine elsewhere.

I assumed that was actually the plan based on http://www.agilitytrains.com/agilitytrains_caseforiep.htm (http://www.agilitytrains.com/agilitytrains_caseforiep.htm), which mentions

• "Bi-mode Super Express Trains (formations that include a diesel engine)..."  Note singular engine.
• "The bi-mode variant will support progressive expansion of electrified network and can be converted to full electric capability once electrification is complete."  Surely that precludes multiple diesel units.
• "There will be a reduction in interior noise levels."

So hopefully our ears will get a smooth ride too!

Except, I see that the above page is not accessible from the main site, so maybe it's no longer true...

well, while i agree its possible to have quiet powered carriages , i was more driving at the fact that unpowered ones could cost less.... but if there is no diesel loco in existence that can do this, then there is little point in discussing it more, i had an idea it had no merit

I think this whole dilema of whther to have bi modes and as i understand it teh IEP will have underfloor power packs in some coaches or loco hauled with engine changes at the end of teh wires.

As for their being no suitable diesel locos then I think the TRAXX Multi Engine is way forward. I anm sure it will not be long before oterh manugafactures produce something similar and possibly better. As Ian Walmsey says in his article it's only putting  a four car DMU in one box.

The trouble with our network is that most if not all lines should be electrified as they they are in Holland and Belgium who have a similar dense network of relatively short main lines all linking up. . Hopefully once we get GWML and MML electrified the absurbities of leaving Penzance and Swansea,  Bristol Birmingham Derby, Marylebone Banbury/Aylesbury, Oxford to Birmingham via Banbury and Worcester with Stratford as well as part of the ex GW Birmingham Sububan electrifcation. Will hopefully become apparent even to the DFT.

In fills such as Ore - Ashford, Uckfield Redhill Guildford Ash Wokingham Reading Basingstoke, TV branches including Greenford branch (served by Crossrail via Ealing and North Acton (interchange with Central Line)  plus GOB and other London links  will be essential, Just these alone would eliminate miles of diesel working. 

Before someone says there is no money OUR BANKS could issue 5% 25 year Electrification  bonds which would be snapped up by the institutions. Don't say it's against EU rules ingore them like the French. In fact the EU could pay for GOB as it goes through some of the most deprived Boroughs in London.

Some excellent points, I wonder if the WAG have been to the EU to beg for money to pay for the wires to Swansea & the valleys  yet?

I'm sure WAG will fund it....

They will have underfloor power packs.  The decision has been made surely?

If they'd gone for engine changes (or diesel hauled EMUs) they wouldn't be getting so much all round grief...

Paul

I'm sure it has!

Well, if WAG canceled the few miles of extra lane on the Heads Of The Valleys Road they could pretty much fund 60 3-car Electrostars and wiring of the whole ValleyLines network, including Maesteg, Ebbw Vale, Swanline and Cardiff to Cheltenham. Unfortunatlly they have signed the contract for the first half of HOTVR, still if they put the remaining half up for the rail project would the EU provide match funding to bring the total back up to the required ^600m? That would leave the Westminister government only having to find the money to wire Swindon to Cheltenham to eliminate any need for bi-mode IEP, the only dificulty being Weston-Super-Mare having a reduced number of direct services to London (and possibly insufficent deisel locos to drag the IEP from Bristol as well as the 5 East Coast drags) if you route the Paddington to Taunton and beyond via Bristol services via Westbury instead to reduce the distance the IC125s run under the wires.

No, it's not. Distributed power with a diesel at one end for IEP is dead. As I said, because they finally realised it simply wouldn't work in a full-length train and changed the design - again.

Just to be absolutely clear for anyone who has missed it, the current IEP plan, no doubt subject to yet more change, is to buy five-car bi-modes with underfloor diesel engines, five-car electrics and eight-car electrics, which will all propel themselves. No diesel locos.


a. What else is like a Class 70 or 66? They were designed by GE and EMD for a very specific purpose - heavy freight. If you want something to drag around light passenger trains at speed and with rapid acceleration, you would start with a blank sheet of paper, not a class 70. And people are very quick to condemn bi-mode trains, from which you could potentially remove diesel engines as wires extend, but not quite so quick with suggestions as to what you would do with all these diesel locos they would have us build instead, should more wires go up - and would the wires actually ever be extended were we to shell out for such locos?

b. Typical station to station times on the Cotswold Line, from the September draft timetable: Oxford to Hanborough, 10 minutes; Hanborough to Charlbury, seven minutes; Charlbury to Kingham, nine minutes (Shipton stops are allowed a generous seven and six-minute split on this leg); Kingham to Moreton-in-Marsh, eight minutes; MiM to Honeybourne, 11 minutes, Honeybourne to Evesham, seven minutes; Evesham to Pershore, eight minutes, Pershore to Worcester shrub Hill, 13 minutes. Average interval nine minutes, oh dear me, i do apologise for being a whole minute out.

Are you really trying to suggest that working any type of diesel train on that type of schedule constitutes a recipe for not running at high power much of the time, never mind any gradients that apply? And there is obvious scope to reduce those times, some trains are already shown in the draft as a minute or two quicker on some legs, so in reality eight minutes is a perfectly reasonable figure to work with.


We don't have a dense network of relatively short main lines - certainly not in Low (and rather small) Countries terms - not least the GWML, which is a long spindly thing, with assorted branches feeding into the trunk route. And the same can be said for ECML and WCML - where to this day lots of the feeder lines remain unwired.

HM Treasury is the Government department that actually matters in all this, not the DfT. The Treasury is not going to be allowing anyone to go around issuing bonds that could count against the Government's balance sheet, however you dress it up. And we're not France.

Rhydgaled. There are lots of difficulties with your plan, relying as it does on fantasy rolling stock building programmes and fleet reshuffles, ignoring why certain of the West Country trains run via Bristol, that WAG cannot spend money in England and that there may well be perfectly valid reasons to widen the Heads of the Valleys road - not least that there is no alternative rail route available to do the journeys it allows.

this is the last thing im saying about this will as i dont wish to argue... i have already stated that i threw an idea out there and after you told everyone why it wouldnt work i accepted that and moved on.... there really is no need to carry on, the only last thing i will say is 'since when were the hst's designed for stop start 8 min intervals? and did i imagine fgw hiring in class 67's

If you're going to 'throw an idea out there' maybe you might care to back it up with some reasoning. And no, HSTs weren't exactly designed for the kind of things they now have to do all over the FGW network every day, but the world has changed, travel patterns have changed, driven in large part by the journey times cuts made possible by HSTs, and they are reasonably well suited to take on the challenge, having lightweight, relatively high-power, high-acceleration (for diesel) traction units, which bear no resemblance a Class 70. And just like an HST, 67s are really designed for long-haul running (on now non-existent mail and parcels trains) at speed, not start-stop. At least working for Chiltern they can stretch their legs a bit, which they wouldn't on the Cotswold Line.

I don't tjink FGW has had 67s, no.

WAG has renamed itself WG (Welsh Government)

Correct.  They will have underfloor engines.  Even the "all electric" trains will have one underfloor power-pack per 8 or 9 coaches (for emergency and depot use).  The bi-mode will have 3 power packs per 5 coaches.

I think I heard they'd added a fourth....

That'll be handy on the ECML then, what with the wires there being somewhat prone to failure.

Does anyone know why this is?
I did see some horrible performance figures for some of these designs but I can't figure out why this is such a challenge.
Surely a small number of larger engines should be more efficient and cheaper to maintain than many small ones? I know that shifting several MW of oompf from one end of a train to another is no mean feat, but this has been solved on TGV for decades (and on Eurostar if you need to fit UK loading gauge) and you need to solve this problem on the full electric model anyway. Surely the fact that the vast majority of vehicles would be identical between electric and bi-mode would be the final nail in the coffin?
I'm sure there is something that I don't understand that swings it in favour of under-slung engines. Is there perhaps a problem with having a non-passenger carrying vehicle in the formation? Would it need to fit on the platform?

I'm just a curious engineer by the way, not making a case here...

Roger Ford of Modern Railways (steady ChrisB!) did a pretty through demolition job on the electric power car plus diesel power car version of the IEP. As far as I can recall he basically did a lot of sums that showed it would not perform on diesel at the level an HST does now, whatever Hitachi claimed. Perhaps not surprising with one engine versus two in an HST. And in order to produce a relatively lightweight 125mph four-axle passenger train vehicle, you are pretty limited in the size of diesel engine you could use.

TGVs do not have distributed power. The traction motors are just on the power cars and the end bogies of the adjacent passenger coaches. The rooftop cable is to distribute power from the pantograph to the power cars.



Having an entire vehicle in a five-coach formation full of a diesel engine and alternator, as was proposed at one stage, would have been a bit of a problem, given the train's pitiful passenger capacity in such a configuration.

Small pedantic point. That's only true of the older TGV PSE (Paris Sud Est) sets. They have 12 DC traction motors. The newer TGV Atlantique, R^seau, Duplex and POS (Paris-Eastern France-Southern Germany) sets have 8 three-phase AC synchronous traction motors on the power cars only.

This is probably not the whole story, but diesel engines are difficult because of new emissions directives.  It is simpler to use small under-floor engines cos they can be derivatives of truck engines that have already jumped through all the emissions hoops than it is to use larger engines that are far less common and where they do have commonality with existing engines they will be in things liek ships that don;t have the emissions requirements to meet.

What became lost in the general noise of discussion at the time, but is quite clear from Roger Ford's figures, is that the (lack of) diesel power issue was actually only relevant to the 10 car bi-mode.  As posted earlier it was analagous to running an HST around with a power car only at one end.

However a single 5 car bi-mode had the same diesel power pack as the 10 car - yet it was still tarred with the same 'underpowered' brush. AFAICS most of the rail media went with a simplified story that all the proposed bi-modes were underpowered.

AIUI the fundamental problem with the original 5 car bi-mode was simply the loss of 20% of the potential passenger carrying capacity, but two 5 car bi-modes running together would have been little or no different to a 2+8 HST capacity wise, especially with 26m carriages. But then there's all the other capacity 'pros and cons' such as duplication of catering facilities, first class, train crew and the lack of through access - as seen with Voyagers running in pairs... 

Paul

It occurred to me that there was something in the original spec that called for commonality between the "commuter" stock and the "express" stock. Clearly this would favour the underslung approach as I can't see the separate power car approach working for 2, 3, 4 or 5 car sets, especially when they're working in multiples.

If this were not a requirement, I can't see that there is anything fundamentally wrong with this architecture for fixed sets of 8 vehicles and over.

Bi-mode diesels of one sort or another certainly seem like they're here to stay.