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Devon & Filton banks - could electrification on uphill sections be possible?

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ac6000cw

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In the Down direction the line limits from Teignmouth are 60/80/90 then 60mph through Newton Abbot. Shortly past Newton Abbot it drops to 55mph and stays at that value to Totnes. Through Totnes the limit is 60mph which stays until Hemerdon where it increases to 80 as far as Tavistock Junction at which point it drops to 60mph. There is a short burst to 70mph past Laira and then a crawl into North Road.

The Up road is similar.

The issue is curvature - spending some money on raising the line limit to a constant 80mph between Newton Abbot and Plymouth would make a considerable difference. Electrification with the existing curves would make no difference to the Exeter - Plymouth times at all.

Yes - when BR did the Crewe - Glasgow electrification, a major component of the modernisation was realigning the track to flatten and raise the speed profile as much as possible and hence make the most of the new motive power. That was what really improved the running times over using double-headed class 50s on the important trains.
 
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Taunton

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when BR did the Crewe - Glasgow electrification, a major component of the modernisation was realigning the track
A lot of this was done on the northern WCML, and especially the ECML, in the late 1960s-70s. It was not rocket science for engineers to calculate which points gave the best return on realignment work, where a restricted curve interrupted full-speed sections. However very little was done south of Weaver Junction because the costs skyrocket when you have overhead equipment already in place to re-site as well. Electrification really does freeze the formation long term.
 

Cowley

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In the Down direction the line limits from Teignmouth are 60/80/90 then 60mph through Newton Abbot. Shortly past Newton Abbot it drops to 55mph and stays at that value to Totnes. Through Totnes the limit is 60mph which stays until Hemerdon where it increases to 80 as far as Tavistock Junction at which point it drops to 60mph. There is a short burst to 70mph past Laira and then a crawl into North Road.

The Up road is similar.

The issue is curvature - spending some money on raising the line limit to a constant 80mph between Newton Abbot and Plymouth would make a considerable difference. Electrification with the existing curves would make no difference to the Exeter - Plymouth times at all.

I thought that's what the line speeds were and they've been similar to that for many years.
Would an electric tilting train knock much time off a Newton Abbot to Plymouth journey? I'd assume they'd climb banks quickly even compared to a Voyager. I'm just asking the question, I don't know the answer...
Interesting thread by the way, especially the last few posts.
 

najaB

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Would an electric tilting train knock much time off a Newton Abbot to Plymouth journey? I'd assume they'd climb banks quickly even compared to a Voyager.
Yes, and additionally your assumption seems sound. The increased speed would come at the cost of higher wear on the track though.
 

ac6000cw

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So I think if you want to reduce journey times between Newton Abbott and Plymouth, spend money on track realignment first to get the most out of the existing (and immediate future rolling stock), then electrify it as part of a larger scheme (to put the icing on the cake).

I get the distinct feeling that tilting trains (with their higher initial and maintenance costs due to extra complexity, as well as higher track stresses/wear and less interior space) have gone out of favour again.
 

najaB

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I get the distinct feeling that tilting trains (with their higher initial and maintenance costs due to extra complexity, as well as higher track stresses/wear and less interior space) have gone out of favour again.
I don't think that they've totally gone out of favour, just that realignment benefits all trains so it's the better option if it's affordable.
 

tbtc

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So I think if you want to reduce journey times between Newton Abbott and Plymouth, spend money on track realignment first to get the most out of the existing (and immediate future rolling stock), then electrify it as part of a larger scheme (to put the icing on the cake)

(as someone who is in the "pro electrification" camp) I'm getting desperate to find crumbs of comfort from recent developments... but at least the bi-modes through Devon mean it's feasible to wire up certain strategic/ shortish sections - not ideal but we don't need to wire over a hundred miles of the GWML to achieve it.

Clutching at straws, I realise!
 

Cowley

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I suppose that having a few tilting trains wouldn't achieve an entirely sped up service when all of the others would be running at the present speed limits. In the current situation which companies would buy the trains anyway?
Maybe as others have said, smoothing out some of the curves and putting wires up would help somewhat. The line does run through some very hilly terrain, running around the bottom edge of Dartmoor as it does. It would be interesting to see where any potential speed gains could be made by easing some of the curvature.
 

randyrippley

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If the Okehampton route was reinstated, how would the grades compare? Is the route potentially quicker?
 

jimm

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Aren`t we supposed to be against coal fired power stations due to climate change ? I would have thought the chances of one being built were slim.

I was referring to the GWR scheme in the 1930s. There was no national power grid then, so a power station on or near the line would have been needed.
 

HSTEd

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I was referring to the GWR scheme in the 1930s. There was no national power grid then, so a power station on or near the line would have been needed.

Regional grids came into being by 1933 and by 1938 the National Grid was established.
It was on the horizon even in 1930 however.
 

GRALISTAIR

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Mods have kindly reopened this thread in view of the article about "spot electrification"

This post serves to bump the thread to the top. :)
 

MatthewRead

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I've wanted them to electrify this stretch for years and I was told in 2011 by a fellow train enthusiast that it just wouldn't happen in any of our life time unless you were a new born baby so basically anyone born before 2011 you won't live to see electrification in Devon :(
 

coppercapped

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Until line speeds are improved, electrification - even 'spot' electrification - will not give any significant journey time reductions on this stretch.

Spend the money where it will be more useful.
 

GRALISTAIR

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I've wanted them to electrify this stretch for years and I was told in 2011 by a fellow train enthusiast that it just wouldn't happen in any of our life time unless you were a new born baby so basically anyone born before 2011 you won't live to see electrification in Devon :(

An enthusiast colleague in the 1980s (30 years older than me) told me Devon Banks was first mooted in the 1930s but I have never been able to find any source/reference for that.
 
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Taunton

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Colind

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Until line speeds are improved, electrification - even 'spot' electrification - will not give any significant journey time reductions on this stretch.

Spend the money where it will be more useful.

I was growing up in Plymouth in the 60s and I remember how the diesel-hydraulics really struggled over these banks. From memory, 1 in 37 in places.

You're right, Coppercapped, electrification might not improve current timings, but it might help us keep what we've got should anyone want to run heavy, underpowered bi-modes on the route.

But nobody would do such a thing, surely??:lol:
 

MarkyT

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It would help with noise and emissions in a sensitive area, and the equipment would not have to be so heavily specified for 140MPH as that will never be possible on that part of the network without new alignments! More discontinuous sections of catenary such as this would strengthen the case for a bimode fleet for the Cross Country and for local trains in Devon and Cornwall. A special mast design might be employed, perhaps a lattice post finished in green to blend in better with the landscape.
 

coppercapped

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I was growing up in Plymouth in the 60s and I remember how the diesel-hydraulics really struggled over these banks. From memory, 1 in 37 in places.

You're right, Coppercapped, electrification might not improve current timings, but it might help us keep what we've got should anyone want to run heavy, underpowered bi-modes on the route.

But nobody would do such a thing, surely??:lol:

:D But I think you might find the results of some calculations of the power-to-weight ratios for D800s and D1000s for their maximum permitted loads over the banks and those for an HST and an Class 802 to be quite interesting.

There are also some other points to be considered - the 800s and train had only 4 driving axles, the 1000s and train only 6. The HSTs have 8 and the 802s even more. To simplify the power circuits the HSTs do not have field weakening so are limited in low speed grunt and the Class 802 have inherently slip-resistant variable frequency 3-phase drives.

They might, just might, get up the banks without too much of a problem.
 

Woody

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The big problem I foresee with even this proposed cut price ‘spot electrification’ scheme is the mostly 60 mph ‘ish' maximum sustainable line speeds that predominate west of Exeter to Penzance. Even an electric powered Hitachi class 802 train could perform little better than the current 40 year old HST trains west of Exeter. So any Dft cost/benefit analysis would probably conclude especially in these austere times that such a scheme was poor value for money.
 

LNW-GW Joint

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Mr Grayling has just re-iterated that there are better solutions than electrification. He should know - he has a 2:1 BA in History

Andrew Adonis also has a degree in Modern History, and a doctorate on the British Aristocracy.
That didn't stop him being a decent Secretary of State for Transport (backing electrification), and now head of the National Infrastructure Commission.
https://en.wikipedia.org/wiki/Andrew_Adonis,_Baron_Adonis

Michael Portillo also had a history degree.
Patrick McLoughlin doesn't have a degree.
Philip Hammond (PPE) and Justine Greening (Economics) were the ones who (with George Osborne - also History) opened the coalition government's wallet for the £38 billion CP5 settlement ("the biggest investment in railways since Victorian times").

.
 

edwin_m

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Michael Portillo also had a history degree.
Patrick McLoughlin doesn't have a degree.
Philip Hammond (PPE) and Justine Greening (Economics) were the ones who (with George Osborne - also History) opened the coalition government's wallet for the £38 billion CP5 settlement ("the biggest investment in railways since Victorian times").

That may have more to do with the fact both parties in the Coalition agreed railway electrification was a Good Thing, but didn't agree on much else in transport (roadbuilding, buses, Heathrow etc). So when a Good News announcement was needed someone would agree another electrification.

Perhaps the answer here is to suggest to DfT that if Devon has banks it must also have bankers, who need high-quality transport links like the bankers in London.
 

The Ham

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Perhaps the answer here is to suggest to DfT that if Devon has banks it must also have bankers, who need high-quality transport links like the bankers in London.

Electrification is more to do with the sheer number of people that are carried on the trains in London and the South East, rather than who is carried on them.

Assuming that electrification was only there for bankers then with 145,000 staff in London (assuming working 220 days a year) that's 64 million passenger journeys a year.

Assuming that they all come in on SWR services into Waterloo then they would take up about 2/3's of the number of people who did so (mostly allowing for the WofE services, which wouldn't be carrying any bankers!). However ALL the other stations in London which are electrified would then would not need to be. That also assumes that none of those bankers live within London.

64 million is tiny compared to the nearly 1 billion (heavy) rail journeys that are made in London and the South East. Even if every one of those bank Industry staff in London made a further return journeys a day (not including Intercity travel) to get above 10% of all (heavy) rail journeys in London and the South East. Even then there would be about 9 other people who were not bankers for every banker on every train.

Even if you meant the wider professional and financial services sector London has circa 700,000, which is less than three times the number in Manchester (240,000) yet with a urban population of something like five times as many as Manchester. Therefore, chances are that Manchester has a higher level of bankers per million people than London. However, definitely has a higher level of people working in finance per million people in London.

(Yes I got that your post wasn't serious, but there are some on here who would think that such retoric was sound and that other regions need to have more investment but are missing out due to the bankers on London getting it all for their trains. Whilst the reason that other regions aren't getting the same, perceived, investment is more to do with less people per million using rail. Of course, that could be due to not having the investment in the past and isn't a reason not to invest in rail in other regions. Which is why I think that there should be more investment in rail than there had been. However even so it is unlikely to look like the same sorts of level, just because there's still a fair amount of train lengthening that can be done fairly easily elsewhere -
even if trains only make it to 8 coaches long - whilst London has a significant number of services which are at the maximum 10-12 coaches long during the peaks).

P.S. personally I would love to see the Devon Banks electrified, but feel that chances are it will be done off the back of the local services justifying it (Devon Metro and all that) with the longer distance services being an added bonus. However, I would also like to see a significant percentage of the rail network being electrified and I'm fairly disappointed that more electrification appears to be off the table for the time being.

If for no other reason than so other reasons than so other reasons could have more of London's cast offs, as there's not enough of a market for all their second hand EMU's yet and with the reduction of DUM's that can be cascaded from London (what with the electrification of the GWML) as otherwise that's going to become more of a problem going forward.

P.P.S. for those that missed it; that last paragraph may have been slightly tongue in cheek.

P.P.P.S. maybe not so slightly and less of the maybe
 

DynamicSpirit

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Until line speeds are improved, electrification - even 'spot' electrification - will not give any significant journey time reductions on this stretch.

I'm confused by this. I've always been lead to believe that the journey-time benefit of electrification usually (for non-high-speed lines) comes from better acceleration, not higher top speeds.

I'm not familiar with the line in question, so maybe I've got it wrong - but as I understand it from this thread, the line is very curvy. Doesn't that imply that there would be lots of places where trains need to slow down and then speed up again, which would therefore make it exactly the kind of route where electrification would give time savings (from the better acceleration)?
 

Peter Mugridge

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I'm confused by this. I've always been lead to believe that the journey-time benefit of electrification usually (for non-high-speed lines) comes from better acceleration, not higher top speeds.

I'm not familiar with the line in question, so maybe I've got it wrong - but as I understand it from this thread, the line is very curvy. Doesn't that imply that there would be lots of places where trains need to slow down and then speed up again, which would therefore make it exactly the kind of route where electrification would give time savings (from the better acceleration)?

Correct on both counts - and electrics do have excellent performance on gradients; after the West Coast Main Line phase 2 works from Weaver Junction to Glasgow were commissioned, the speed restriction of 75mph imposed on Shap at the time was not because they couldn't go faster but because they needed to restrict the locomotives of the time to that speed on the climb in order to stop them from overloading themselves.

In other words - the long hard gradient itself was no longer the restricting factor on speed.
 

Taunton

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I was growing up in Plymouth in the 60s and I remember how the diesel-hydraulics really struggled over these banks. From memory, 1 in 37 in places.
Not so much a feature of poor power as substantial trains. In the 1960s Plymouth services made up to 12 or 13 coaches, at infrequent intervals, were common in summertime. Warships, with just four driving axles, could find this a real challenge in the rain. One of the main advantages of a Western over a Warship was the additional driving axles. More power, but less per axle, which of course helped adhesion. I remember Warships slipping in the rain when leaving Taunton station on the flat.

Be glad the WR was not given Class 40s, which staggered up the 1 in 75 of Shap at about 25mph flat out, compared to the 1 in 36 of Dainton. I always felt the best WR hydraulic performance was on the heaviest trains on the region, the Paddington to South Wales services, which for the first couple of years of their dieselisation were given nothing more than a Hymek. They used to come singing over the top of the long climb out of the Severn Tunnel, rising up under the A38 road bridge into Patchway station with about 13 on at a really good clip.
 
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