Great Western Railway Future Stock

[swt_passenger]

Indeed I don't think there's much left up there now. What was left was in the process of becoming an NR depot for their track machines, but I can imagine that all the fueling equipment was removed when the new depot opened.
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I think the main 'shed' is still there, and the sidings were generally shortened, but am also pretty sure the new feeder lines and new access road layout within the upper triangle took out the fuel tank area, which was near the southernmost part of the site.

 

[jimm]

Indeed I don't think there's much left up there now. What was left was in the process of becoming an NR depot for their track machines, but I can imagine that all the fueling equipment was removed when the new depot opened.

It has been talked about, that Bedwyn is likely to be reached by a 387 on Batteries. That's why the GW 387s were ordered with the similar batteries to that tried on the 379 trial unit. I suppose a Turbo could be retained for the Reading to Bedwyn services, but IIRC the through ones are set to be turned into 387 operated.

GWR may have been looking at the idea of acquiring some battery-equipped 387s but it's still no more than an idea right now - the economics of the 379 project didn't look brilliant when projected over a long period in an analysis Modern Railways did - as for batteries, I'm not sure what you mean. The 379 conversion required six rafts of batteries to be fitted under the train to provide the traction power off the wires.

And in their response to the Network Rail Western Route strategy consultation in January last year, the then FGW said clearly they wanted an early extension of electrification to Bedwyn.

 

[Class 170101]

To be honest the sooner the wires get from Newbury / Bristol / Chppenham / Bath to Plymouth, filling in that triangle, the better.

 

[leomartin125]

I don't think that a 365 would have any chance of fitting on the Marlow branch, given that a 2-car class 165 or 166 will literally only just fit into Bourne End

Well Network Rail want to electrify the Henley Branch and Marlow Branch, so I doubt these will see 166's for much longer in all honesty. No idea what will replace them.

 

[swt_passenger]

Well Network Rail want to electrify the Henley Branch and Marlow Branch, so I doubt these will see 166's for much longer in all honesty. No idea what will replace them.

Depends which sources you take as showing current policy. The Western route study last year showed all branches being electrified.

But NR's current enhancement plans (post the Hendy review) still show the Marlow branch has been kicked into the long grass, it was dropped from the CP5 plans quite a while back whereas the other branches, (now including Reading to Basingstoke), were left in...

This is the latest available statement, note the bolding I've added:

Thames Valley Branch Lines and Southcote Junction to Basingstoke Electrification
W003
[...]
Network Rail’s Obligation
 Deliver a 25kv AC electrification solution for the Twyford to Henley-on-Thames, Slough to Windsor and Eton Central to enable electric traction to operate.
 For the avoidance of doubt, electrification of Maidenhead to Bourne End and Marlow branch lines is not included, but Network Rail will support Great Western Railway and other stakeholders to develop their capacity improvements proposals for this section
 Develop to GRIP Stage 3, 25kv AC electrification solution between Southcote Junction and Basingstoke.

 

[JN114]

Bourne End was always going to be a problem.

The "Down" (Marlow) platform is very tight, there's approximately 55m useable length between the stops and the points - not long enough for any currently available AC EMU. There's also little to no possibility of extending the platform at either end, certainly not by the 30+ metres required to operate EMUs

Current musings are to remodel the junction slightly at Bourne End to allow trains off the Marlow branch to access either platform (a layout that existed in the 1960s) to enable trains to "pass" at Bourne End. This would allow a similar morning peak frequency to that currently enjoyed, while continuing to allow Marlow - Paddington to be done with only 1 change post crossrail (albeit at Maidenhead as opposed to Marlow)

Service would operate with 2x 2/165 - a pool of ~8 units based at Reading could then operate Marlows (2), Greenford (1), N Cotswold halts shuttle to Oxford (1-2), Bedwyn stoppers (2) with 1 spare/maintenance. They would join 8-10 3/166 kept to work Basingstokes and North Downs services.

Kennet line service would be re-jigged. Existing 1Kxx Paddington - Bedwyn fasts would terminate at Newbury and be operated by EMUs (likely 387s). Reading Newbury stoppers would extend through to Bedwyn. Kintbury and Hungerford would retain their London through trains by being called at by the Semi-Fast Paddington- Exeter Bo-modes.

 

[SpacePhoenix]

Depends which sources you take as showing current policy. The Western route study last year showed all branches being electrified.

But NR's current enhancement plans (post the Hendy review) still show the Marlow branch has been kicked into the long grass, it was dropped from the CP5 plans quite a while back whereas the other branches, (now including Reading to Basingstoke), were left in...

This is the latest available statement, note the bolding I've added:

Is a 2 car AC EMU even physically possible anyway, with the space needed for everything (compressors, transformer, etc)?

 

[AM9]

Is a 2 car AC EMU even physically possible anyway, with the space needed for everything (compressors, transformer, etc)?

Why not. The transformer would only need to be sized for 750-1000 MW, - there would only be a need for one or maybe two motor bogies, and with just eight axles, the compressor would be smaller. Most of the MKIII ac EMUs (except the 319s) I believe have all of the equipment (rated for a 4-car set) accomodated within a 20m motor car, the other three being simple trailers.
The only issue would be the location of the pantograph as the 2-car class 309/1s were disliked by many drivers owing to arcing at the pantograph being immediately above the driving cab.

 

[Class172]

Is a 2 car AC EMU even physically possible anyway, with the space needed for everything (compressors, transformer, etc)?

There's the Class 456, which is the sole example of a EMU currently, though I don't know if the AC/DC difference would have an influence. I suspect it would be possible though.

 

[AM9]

There's the Class 456, which is the sole example of a EMU currently, though I don't know if the AC/DC difference would have an influence. I suspect it would be possible though.

As an additional thought, if there is room to fit a (nearly) 500hp diesel motor, a gearbox/drive, a fuel tank, a compressor and an air conditioning unit in a 23m turbostar body, finding space for just a transformer, electronics, compressor and air conditioning unit should be relatively easy.

 

[Philip Phlopp]

There's the Class 456, which is the sole example of a EMU currently, though I don't know if the AC/DC difference would have an influence. I suspect it would be possible though.

Yes, no issues with building a 2 car AC unit, the Class 456 has more than enough space under the driving trailer vehicle for a transformer (as an indicator of space/scale), but you really wouldn't want to run a 2 car EMU.

The problem is pantograph spacing for multiple working, and running a decent length formation - 3 pantographs is the limit for 110mph operation on the Series 1 OLE, that only buys you a 6 car formation. The design would be very non standard too, having a driving vehicle with a pantograph well.

All doable, but all at a cost and with significant disadvantages.

 

[Mikey C]

There's the Class 456, which is the sole example of a EMU currently, though I don't know if the AC/DC difference would have an influence. I suspect it would be possible though.

The 466s are a more recent example.

The number of AC 2 car EMUs for such branches would be tiny though, and likely to be non standard with the 365s and 387s operating the other GWR services

 

[edwin_m]

Yes, no issues with building a 2 car AC unit, the Class 456 has more than enough space under the driving trailer vehicle for a transformer (as an indicator of space/scale), but you really wouldn't want to run a 2 car EMU.

The problem is pantograph spacing for multiple working, and running a decent length formation - 3 pantographs is the limit for 110mph operation on the Series 1 OLE, that only buys you a 6 car formation. The design would be very non standard too, having a driving vehicle with a pantograph well.

All doable, but all at a cost and with significant disadvantages.

Presumably if coupled together they would need a speed restriction or one unit would have to be dead with pan down. But with only a small fleet of 2-car units on specific diagrams this wouldn't happen very often.

A 2-car coupled to a 4-car would be no worse than two 3-cars coupled to each other - would two (or 3) 3-cars be permitted to run at 110mph?

However I do agree a short EMU is very unlikely because I don't believe any of the EMU product ranges designed for the UK allow for the possibility of a driving transformer/pantograph vehicle.

 

[AM9]

Presumably if coupled together they would need a speed restriction or one unit would have to be dead with pan down. But with only a small fleet of 2-car units on specific diagrams this wouldn't happen very often.

A 2-car coupled to a 4-car would be no worse than two 3-cars coupled to each other - would two (or 3) 3-cars be permitted to run at 110mph?

However I do agree a short EMU is very unlikely because I don't believe any of the EMU product ranges designed for the UK allow for the possibility of a driving transformer/pantograph vehicle.

It's looking very much like the Marlowe/Bourne End branch will have to one day (soon) lose its direct service to Paddington as it would just be too big a waste of a mailine path.

 

[jimm]

It's looking very much like the Marlowe/Bourne End branch will have to one day (soon) lose its direct service to Paddington as it would just be too big a waste of a mailine path.

The through services are slated to stop in May next year - when GWR electric trains are expected to start running between London and Maidenhead.

 

[AM9]

The through services are slated to stop in May next year - when GWR electric trains are expected to start running between London and Maidenhead.

Then despite the inevitable protestations of the (relatively few) passengers who come from stations on that branch, that will surely become permanent.

 

[swt_passenger]

The through services are slated to stop in May next year - when GWR electric trains are expected to start running between London and Maidenhead.

I see that the Western Route study also ends the Henley through services by 2019. It gives that same date for cessation of Marlow through running, but that was written before the recent idea to start electric services on the mainline as soon as wiring was complete to Maidenhead.

 

[43096]

The 466s are a more recent example.



The number of AC 2 car EMUs for such branches would be tiny though, and likely to be non standard with the 365s and 387s operating the other GWR services

Going back in time there were some 2-car Class 309s which were later extended to 4-car.

 

[jimm]

Then despite the inevitable protestations of the (relatively few) passengers who come from stations on that branch, that will surely become permanent.

Certainly will be permanent, whatever eventually happens in terms of wiring to Bourne End and/or Marlow.