The best way to electrify the Chiltern Network and the Snow Hill Lines

[Trainbike46]

From https://www.railforums.co.uk/threads/chiltern-tender-for-20-70-units.252837/page-4

Make electrification plans now! Or maybe use other diesels which will be withdrawn soon.

What is the best way to go about electrifying the Chiltern Network and the Snow Hill Lines?
- where to start?
- Any particular problem areas?
- Dual electrification for the 4th rail areas shared with LU, or dual voltage units?

Personally, I would start at the Birmingham end, by electrifying the Snow Hill lines, and then work outwards towards the termini, including London Marylebone. For the section that is shared with LU, I would retain 4th rail, possibly with slight extensions, and use dual voltage units

 

[Bletchleyite]

Start from both ends, with the Wycombe local service and the Snow Hill Lines first. Then fill in the middle.

It's such a shame Aylesbury wasn't brought into Crossrail as was in the original BR plan (with relevant significant housing development). But we are where we are. I'm inclined to think battery is the way to deal with that (and the Risborough branch) provided the fourth rail can provide enough to keep them topped up, but if you wanted to wire the lot to make the depot stuff easier (unless you built a new EMU depot elsewhere on the route) then just use dual power units for that, with OHLE north of Amersham and fourth rail south of it.

 

[HSTEd]

Personally I think the solution to the Aylesbury problem is to cut a deal with TfL to extend the Metropolitan line out there.
The third rail prohibition specifically excluded TfL four rail installations and only a handful of footbridges would be needed for the conversion.

Post coronavirus there is likely space for two trains per hour at Baker Street, and Chiltern could continue to serve Aylesbury (and Vale Parkway) via Princess Risborough

 

[cle]

If Didcot-Oxford was wired, I would aim for Oxford first. That would mop up 3-4tph instantly. Those time savings alone could probably enable another service to flight.

But as it stands, the whole route is valuable. You’d try tack on Leamington-Coventry too (with some more passing opps or doubled).

The Birmingham lines are a little messy: two routes to Stratford, other side extends to Worcester sometimes etc - ex-London is more self-contained and frequent.

But the Met is a whole other thing and I guess Aylesbury like Stratford has a second, rural way in.

Do the lot, inc Didcot and Cov.

 

[anthony263]

Personally I think the solution to the Aylesbury problem is to cut a deal with TfL to extend the Metropolitan line out there.
The third rail prohibition specifically excluded TfL four rail installations and only a handful of footbridges would be needed for the conversion.

Post coronavirus there is likely space for two trains per hour at Baker Street, and Chiltern could continue to serve Aylesbury (and Vale Parkway) via Princess Risborough

More fast trains on the MET line even off peak but yes definitely think an extension to Aylesbury is needed.

Don't know about Aylesbury parkway though

 

[Bletchleyite]

Don't know about Aylesbury parkway though

AVP is likely to become much busier as a load of housing estates continue to go up around it (it was formerly in the middle of a field). I suspect in time given that Aylesbury isn't really a regional destination it will be busier than that.

Slowing its service to nearly 90 minutes to Marylebone or serving it only with East West Rail (if it ever happens) wouldn't be a good plan, so if going the Met way you'd need to take the Met all the way out there.

 

[HSTEd]

AVP is likely to become much busier as a load of housing estates continue to go up around it (it was formerly in the middle of a field). I suspect in time given that Aylesbury isn't really a regional destination it will be busier than that.

Slowing its service to nearly 90 minutes to Marylebone or serving it only with East West Rail (if it ever happens) wouldn't be a good plan, so if going the Met way you'd need to take the Met all the way out there.

I think the 90 minute journey time for AVP to Marylebone is mostly a function of multiple changes isn't it?
In this situation, wouldn't you run a through AVP to Marylebone train, at which point journey times would be more like 65 minutes, which isn't really much slower than now.

 

[Bletchleyite]

In this situation, wouldn't you run a through AVP to Marylebone train, at which point journey times would be more like 65 minutes, which isn't really much slower than now.

You could run a faster one that way but could it be pathed? The few through services are all stations at about 1h15 to Aylesbury (add another 5 for AVP), which is really too slow.

Downgrading an up and coming station doesn't seem sensible - it's going to need an increased service (all trains rather than half of them) at some point as its popularity grows.

 

[Energy]

Part of the Chiltern route used to be single track, how feasible is it to run a quiet mid-day service and revert to single track operation in sections with the other being used to pile for twin track cantilevers? I presume they don't have the required signaling.

 

[HSTEd]

You could run a faster one that way but could it be pathed? The few through services are all stations at about 1h15 to Aylesbury (add another 5 for AVP), which is really too slow.

Downgrading an up and coming station doesn't seem sensible - it's going to need an increased service (all trains rather than half of them) at some point as its popularity grows.

I guess the obvious solution is to send the Met all the way to Aylesbury Vale Parkway, although that might annoy people if they want access to Aylesbury from the North for East-West Rail at any point.
I do think that Met conversion to Aylesbury is the way to go however, it solves a lot of annoying difficulties and turns the Chiltern system into just any other railway.

 

[Trainbike46]

I guess the obvious solution is to send the Met all the way to Aylesbury Vale Parkway, although that might annoy people if they want access to Aylesbury from the North for East-West Rail at any point.
I do think that Met conversion to Aylesbury is the way to go however, it solves a lot of annoying difficulties and turns the Chiltern system into just any other railway.

I see your point, and I don't think sharing between EWR and the metropolitan for the section between Aylesbury and Vale parkway would be an issue if it ever happens.

However, with the depot in Aylesbury it is worth considering whether it would cause issues if it can only be accessed via Princes Risborough. And if it does cause issues, whether those issues justify a different approach, or moving the depot?

 

[HSTEd]

I see your point, and I don't think sharing between EWR and the metropolitan for the section between Aylesbury and Vale parkway would be an issue if it ever happens.

However, with the depot in Aylesbury it is worth considering whether it would cause issues if it can only be accessed via Princes Risborough. And if it does cause issues, whether those issues justify a different approach, or moving the depot?

The depot doesn't appear to have much storage space for trains, is it a primary maintenance facility?

If it is a relatively minor facility the question should be asked of how critical that facility is in a world where Chiltern doesn't have to provide trains for Aylesbury-London via Harrow any more.
Ofcourse, for a large part of the current Chiltern fleet, the only option is already via Princes Risborough - if they don't have trainstops fitted.

 

[cle]

Could Aylesbury-Amersham survive as a shuttle? Maybe Amersham is where the EWR MKC service begins. I expect there would be many howls. But then again, there would be for the whole thing being a tube journey, even if the speed is about the same.

Ideally the Princes Risborough route would be used more - as it is faster (or could be, with stopping patterns) - if not more direct - and serves High Wycombe too.

But the decision to not invest in doubling/speeding up that route for EWR (and Chiltern) makes it very difficult. It's very short too.

 

[Trainbike46]

Could Aylesbury-Amersham survive as a shuttle? Maybe Amersham is where the EWR MKC service begins. I expect there would be many howls. But then again, there would be for the whole thing being a tube journey, even if the speed is about the same.

Forcing transfers in Amersham would make the journey much less attractive - better to either extend the met line or retain chiltern via Amersham

 

[HSTEd]

Could Aylesbury-Amersham survive as a shuttle? Maybe Amersham is where the EWR MKC service begins. I expect there would be many howls. But then again, there would be for the whole thing being a tube journey, even if the speed is about the same.

I think it is somewhat instructive that Amersham sees comparable passenger numbers for the tube and national rail, with approximately comparable service levels.
I don't think there is a strong antipathy to the Met, and indeed it has several advantages.

I'm not sure there would be true outrage if two trains per hour to Marylebone via Harrow were replaced with two trains per hour to Bakers Street.

 

[zwk500]

If Didcot-Oxford was wired, I would aim for Oxford first. That would mop up 3-4tph instantly. Those time savings alone could probably enable another service to flight.

Personally I'd still aim for Oxford regardless of what happens with the GW side.

The Birmingham lines are a little messy: two routes to Stratford, other side extends to Worcester sometimes etc - ex-London is more self-contained and frequent.

Messy but worth tackling (especially with battery trains) as one 'Snow Hill lines' task, with Chiltern happening to contribute the benefits as well

Part of the Chiltern route used to be single track, how feasible is it to run a quiet mid-day service and revert to single track operation in sections with the other being used to pile for twin track cantilevers? I presume they don't have the required signaling.

There's certainly Bi-Di in parts of the Chiltern Main Line. I highly doubt there's enough capacity for using it during the day without thinning the service too far though. There's also the move away from keeping adjacent lines open to factor in. NR are very conscious of the additional risk to staff if an adjacent line is open to traffic.

 

[Trainbike46]

The depot doesn't appear to have much storage space for trains, is it a primary maintenance facility?

It is a maintenance facility - though how important it is for Chiltern as a whole I do not know. Apparently it maintains 165s and 168s

If it is a relatively minor facility the question should be asked of how critical that facility is in a world where Chiltern doesn't have to provide trains for Aylesbury-London via Harrow any more.
Ofcourse, for a large part of the current Chiltern fleet, the only option is already via Princes Risborough - if they don't have trainstops fitted.

I guess there is four possible outcomes if extending the met line to Aylesbury (Vale Parkway):
- depot acces exclusively via Risborough is fine as-is
- dual-track the line via risborough to ease depot access (as well as the timetable)
- Have a maintenance depot elsewhere on the Chiltern system to replace Aylesbury
- retain Chiltern access to Aylesbury via Amersham

I do not know which is best, but it is something that needs considering

 

[The Planner]

Part of the Chiltern route used to be single track, how feasible is it to run a quiet mid-day service and revert to single track operation in sections with the other being used to pile for twin track cantilevers? I presume they don't have the required signaling.

Apart from Princes Risborough to Aynho, none of it is bi-di. Even then you wouldn't be able to run much of a service.

From https://www.railforums.co.uk/threads/chiltern-tender-for-20-70-units.252837/page-4


What is the best way to go about electrifying the Chiltern Network and the Snow Hill Lines?
- where to start?
- Any particular problem areas?
- Dual electrification for the 4th rail areas shared with LU, or dual voltage units?

Personally, I would start at the Birmingham end, by electrifying the Snow Hill lines, and then work outwards towards the termini, including London Marylebone. For the section that is shared with LU, I would retain 4th rail, possibly with slight extensions, and use dual voltage units

It will be done from the southern end.

 

[Trainbike46]

Apart from Princes Risborough to Aynho, none of it is bi-di. Even then you wouldn't be able to run much of a service.

It will be done from the southern end.

Are there actual plans happening? (fingers crossed)

 

[The Planner]

Are there actual plans happening? (fingers crossed)

Its being looked at, which is about it. None of its funded.

 

[Nicholas Lewis]

Needs wiring at 25kV and thats coming from someone who spent the 80's constructing the Southern DC infill schemes but will need a fleet of BEMUs to cover Aylesbury otherwise you will no doubt be in a whole world of pain with power supply capacity on the Met line. Anyhow aint going to happen anytime soon

 

[eldomtom2]

Would there be any issues with converting Amersham - Harrow-on-the-Hill to whatever the precise term is for the system used by sections shared by the Overground and Underground?

 

[Mr. SW]

If the Met were extended to Aylesbury, this presents several questions. Initially, would the present/future trains handle that sort of traffic? It's quite a long way and riding on a longitudinal seat on a train really built for a metro service with its multiple doors and 60mph/100kmph top speed sounds a little grim for the distance involved.

Would they need to construct dedicated vehicles with a higher top speed with more transverse seating, retention toilets etc. If there was a higher top speed, would the 4-rail power supply be able to handle it? And would the trains be capable of running beyond Baker Street?

This suggests to me that the Met should be left as it is.

As for Birmingham Snow Hill: No comment. Brum isn't a place I really know.

 

[Mikey C]

If the Met were extended to Aylesbury, this presents several questions. Initially, would the present/future trains handle that sort of traffic? It's quite a long way and riding on a longitudinal seat on a train really built for a metro service with its multiple doors and 60mph/100kmph top speed sounds a little grim for the distance involved.

Would they need to construct dedicated vehicles with a higher top speed with more transverse seating, retention toilets etc. If there was a higher top speed, would the 4-rail power supply be able to handle it? And would the trains be capable of running beyond Baker Street?

This suggests to me that the Met should be left as it is.

Agreed. Aylesbury is a significant distance past Amersham, I like the S stock, but they're not ideal for such a long journey. Low backed seating, much of it sideways, and designed for acceleration rather than top speed.

Also worth noting that the Amersham to Aylesbury line is faster and serves more important intermediate stops than the Princes to Aylesbury line, which is a slow and sleepy branch line. Hence the use of the bubble car on it for many years.

 

[cslusarc]

I would start electrification from Marylebone because Chiltern's 165 are older than any Turbostar at WMR.

 

[Irascible]

Would they need to construct dedicated vehicles with a higher top speed with more transverse seating, retention toilets etc. If there was a higher top speed, would the 4-rail power supply be able to handle it? And would the trains be capable of running beyond Baker Street?

You would, presumably, need new stock anyway, so it might as well be dedicated. Is there really a problem in changing at Baker St though?

 

[HSTEd]

If the Met were extended to Aylesbury, this presents several questions. Initially, would the present/future trains handle that sort of traffic? It's quite a long way and riding on a longitudinal seat on a train really built for a metro service with its multiple doors and 60mph/100kmph top speed sounds a little grim for the distance involved.

Would they need to construct dedicated vehicles with a higher top speed with more transverse seating, retention toilets etc. If there was a higher top speed, would the 4-rail power supply be able to handle it? And would the trains be capable of running beyond Baker Street?

The line between Amersham is only about 22km, and has a top speed of 75mph.
A train running at 60mph, even if both trains have infinite acceleration, would only lose 2 minutes.

Given the far superior acceleration of S-Stock compared to a Networker Turbo, I am not even sure any time would be lost at all! The current service manages to take 22 minutes to cover 22 kilometres!

If another batch of Movia vehicles was required to make up the numbers, it could be built with more of the S8 style tranverse seeting but I don't think toilets would really be workable.
London Underground has no facilities to work with toilets, it would be far more sensible to make sure toilets were available at Aylesbury and Amersham.

If you just built S-stock then the trains could operate wherever you wanted on the subsurface lines, although Baker Street is pretty clearly already a superior terminus to Marylebone in terms of connectivity.

I don't have a sectional appendix for the LU lines so I can't speak to journey time lost over that section, but people are apparently happy to ride LU in from Amersham!

 

[Energy]

I don't have a sectional appendix for the LU lines so I can't speak to journey time lost over that section, but people are apparently happy to ride LU in from Amersham!

70mph max speed for most of Aylesbury - Amersham. The 8mph max speed lost would be easily compensated by better acceleration.

After electrification, the biggest problem is Aylesbury depot. Chiltern undertakes heavy maintenance on 165 and 168s there, and assuming the route (apart from the branch) goes to London Underground only, it would only be accessible on a single-track route from Aylesbury, which would only be accessible on a single-track branch line. If Chiltern received new stock at the same time it would make sense to have the new depot elsewhere, like Banbury.

 

[Mgameing123]

Personally I think the solution to the Aylesbury problem is to cut a deal with TfL to extend the Metropolitan line out there.
The third rail prohibition specifically excluded TfL four rail installations and only a handful of footbridges would be needed for the conversion.

Post coronavirus there is likely space for two trains per hour at Baker Street, and Chiltern could continue to serve Aylesbury (and Vale Parkway) via Princess Risborough

Or make an exception to the third rail ban for Chiltern. I doubt TFL would want to extend the Met Line.


From: https://www.railforums.co.uk/threads/chiltern-tender-for-20-70-units.252837/page-4#post-6764889

That would be down to NR, not Chiltern and it would take many years to complete, hardly a quick fix.

But if we buy new diesel trains now then we will ruin the business case for electrification.

 

[zwk500]

Or make an exception to the third rail ban for Chiltern. I doubt TFL would want to extend the Met Line.

The grounds for an exemption would be quite weak, as Dual-voltage trains and OLE are viable on this line, especially for future extensions of the OLE netwrok.

But if we buy new diesel trains now then we will ruin the business case for electrification.

It makes no difference to the electrification case, as new trains would need to be procured anyway. If anything, potential electrification harms the case for new diesel trains (although enough stock is needed nationally that new diesel could be relatively easily cascaded, heaven knows GWR are short of Stock).