Corridor connections are really not feasible on 125mph trains due to crashworthiness issues
And aerodynamics too surely? I don't think any loco/unit with a flat leading end (at least in the UK) does more than 110mph.
therefore when there is portion working eg Oxford-London on services which need fewer seats on the Cotswold Line (or perhaps to Stratford-upon-Avon in future as well) this (corridor-less trains in multiple) is the way you will have to do it.
Or you run everything you want to portion-work using 100mph stock with corridor-connections and ensure trains that are designed to go over 110mph have enough carriages in them that they don't need to be run in multiple (for example use a 7-car class 221 bi-mode with Selective Door Openning on London - Worcester instead of 2x 5-car bi-mode IEPs). If you absolutely have to have portion working on London - Worcester to provide enough London - Oxford capacity there is a problem, you need an electric unit and a bi-mode unit in multiple and have some way of ensuring the correct passengers get the correct portion and that passengers for stops before Oxford only get in the portion that terminates at Oxford (so passengers for stations beyond Oxford are more likely to get a seat). Very difficult.
London-Oxford is essentially an outer-suburban length journey. Lots of the passengers doing that run don't want refreshments (or bought them at the station), so doubling up catering is hardly necessary.
That's a good point I suppose, you'd need some 5-car electric units without buffet cars for the PAD - Oxford portion and 6-car bi-modes (reduced to 23m vehicle lengths, hence an extra coach) with buffet for the Worcester portion. I would imagine that some of the Hereford services (those which justify IC125s at present) would need to remain IC125 operated.
As I said back up the thread, on the Cotswold Line you are talking a dozen platforms to extend at the main stations
So what's wrong with a 7-car unit (23m vehicles) with Selective Door Openning?
Money will have to be spent to make some West Country routes able to take 165s and 166s post-2016, or should they not bother with that either?
They should look carefully at where else they could send them. Some of the routes east of the ECML around Newcastle, and of course the Chiltern line, are cleared for 166s and 165s I beleive, they could be deployed there instead. If Chiltern and Northern won't/can't have them, clearing Bristol - Severn Beach and Bristol - Taunton for them might be a good plan, I really hope Bristol - Portsmouth isn't cleared for them as 158s are better suited for the service than 166s/165s I think.
I don't want anything from the Voyager/Meridian family anywhere near a GW express service (hands up anyone else who does, apart from the anti-bi-mode faction) - though now I come to think of it, how about one for Pembroke Dock trains on summer Saturdays, since you're so keen to foist them on others, as this is presumably the "rural branch" you have in mind? (though why an entire rolling stock strategy should be based around a line with a handful of summer Saturday through trains beats me)
A bi-mode Voyager (or a bi-mode anything) for the Pembroke service would be like trying to crack a nut with a screwdriver. All that is needed is 6 mark3s hauled by a diesel loco from Portsmouth (or Bristol if there's a problem with running from Portsmouth), I don't think it really needs to be a London service it just needs the capacity.
An all nine-car fleet is incredibly inflexible (witness the current return of 180s to FGW, where the only option available for London-Oxford/Cotswold services the past three years has been an HST - ie lots of empty seats off-peak - or a Turbo configured for suburban duties).
But you still need something longer in the peaks, would a mix of 7-car and 9-car sets do it without the need to run any 125mph stock in multiple?
As has previously been discussed, the diesel engines will be removable and capable of inserting into other trains.
As has also been discussed, each of these diesel engines will cost £250k. I'd be supprised if you could fit one of these engines under a Sprinter and I wouldn't be supprised if it'd use more fuel than the Sprinter's old engine if you did make it fit. Therefore, I'd guess the engines either have to stay in the IEPs for the full 30-year lifespan or be thrown away (and at £250k each I think throwing them away is unlikely).
If bimode IEP are introduced in 2017 (as is planned) then it may still take a couple of years to electrify all of the proposed GWML lines (assuming of course that everything goes to plan in terms of electrification...).
Apart from Swansea, I think all the GWML wiring was supposed to be finished by the end of 2017, and I'd expect Swansea wouldn't be far behind since I think only Bristol Parkway - Cardiff was scheduled for 2017 and the rest of GWML was meant to be wired up by end of 2016.
the sky will not fall in if you couple up two IEPs that don't have a corridor connection.
No, but if the portion that gets detached at Oxford is at the London end and somebody for Worcester is about to miss the train and boards the Oxford portion they won't be too pleased since they might end up with an hour wait at Oxford (and, it being the London end, they may be more likely to have to stand). The point about passengers having to stand is also relevant, if lots of pepole board the nearest coach in a hurry they can't spread out along all ten coaches because you can't walk between coupled 125mph units.
So are you saying that Swansea should keep HSTs into 2018, irrespective of wires being at Cardiff by spring 2017? Why would you not run bi-modes on Swansea services if you could while wiring is completed west of Cardiff?
Yes, retain IC125s on the Swansea services until you can run a pure-electric train to Swansea under its own power, unless you can run it with bi-modes without having to build more bi-modes than you need once the wires are all up.
And good luck with writing a GWML timetable for that period, given the drastic differences in performance between diesel and electric traction. Even pathing the few West Country trains that go via Bristol will pose a challenge on an otherwise all-IEP railway west of Reading.
It will not be an all-IEP railway west of Reading - the PAD - Oxford slow services will be 100/110mph EMUs will they not (and the Pembroke Dock summer service is in the ITT I believe, so will need non-IEP stock unless IEP is reduced to 23m vehicles or the franchise allows the GreatWestern Pembroke Dock service to be run to/from a destonation other than London Paddington). The timetablers will have a challange on their hands anyway, six months to a year extra IC125 operation on London - Swansea isn't going to make it that much harder is it?
Will it be worth spending several hundred thousand pounds to rebuild trains that are going to see another decade at best and at the same time use engines which are awfully polluting by modern standards? A re-engining programme will put the cost up even further.
The engines under Sprinters may be less modern, but the units are lighter and less powerful than modern units so I'd be supprised if their emmisions aren't similar to modern regional units (and less than Voyagers).
The Class 22x will not require enormously expensive rebuilds to continue in operation, and as far as I can think of there are no routes that East Midlands Trains or similar operate that will be not be electrified at the same time as the Midland Main Line that would have any significant use for them.
A few 222s will be needed for the services that extend beyond Nottingham, Corby and Shefield will they not?
The 1tph Swansea services Off peak, would be 2x5 car bi-modes until Cardiff, with splitting and detaching at Cardiff, with one portion going to Swansea.
That is a right mess, I think Swansea probably will need more than 5-car and it'd be bi-mode under the wires the whole way. There simply are not enough IEP electrics in the plans.[/QUOTE]
I expect Chiltern may ask for a few extra 165s, but they certainly don't need 37 sets, never mind the 21 166s.
Couldn't they have 166s/165s to cascade their 23 168s/172s to other operators? That should reduce the ammount of guage clearance required, provided 168s are convential dimensions not 165/166 dimensions.
If all manner of other dmus are to culled due to DDA, then the 22Xs will have to be used in places that they don't go now, to free Class 170s from their current XC and Scotrail (Aberdeen and Inverness expresses need more capacity than 170s offer) operations to replace 15X and 16X trains elsewhere
In my opinion, without ordering new DMUs it will be hard enough just to replace the Pacer fleets. If we're lucky, the 150/1s might go as well but that's that I think (and they'd better not scrap anything with a higher number until all the Pacers are 150/1s are gone). If the 156s and/or 158s go, we need a new build of similar DMUs to replace them, 170s (with their outer-suburban 1/3, 2/3 doors) are only fit for replacing Pacers and 150s, they aren't regional express trains like 158s (and they need corridor connections, for portion working).
Capping IEP performance? I can see that one going down well in Oxford, Swindon, Bath, Bristol, Newport and Cardiff. "Well, you've endured years of disruption for electrification, resignalling and Reading rebuilding but your shiny new trains aren't actually going to use their superior acceleration to speed up your journeys for well over a year because the wires aren't finished to Swansea."
Just one year, they'll get their accerated journeys eventually, and fairly soon - it's not like they'll have to wait decades for the government to agree to electrify the line.
