Why not more tilting stock?

supervc-10

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Regarding cant deficiency- does the increased wear still apply to tilting stock? My understanding was that tilting was purely a passenger comfort issue. Does this mean that a Pendo pays higher track access charges than an equivalently heavy and quick train?
 
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Bald Rick

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Regarding cant deficiency- does the increased wear still apply to tilting stock? My understanding was that tilting was purely a passenger comfort issue. Does this mean that a Pendo pays higher track access charges than an equivalently heavy and quick train?

Yes, the track can’t tell what the train is doing. All it experiences is the cant deficiency.
 

gsnedders

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2) Linslade Tunnel is 125mph EPS, but only 90mph PS. Part of this is curvature (it’s the one part of the WCML that still scares me) but part of it is air pressure for passengers on trains. Pendolinos, Voyagers, (and one assumes) the Hitachi trains are pressure sealed for this responsibility. Most other passenger trains are not. So what should the linespeed be there?
Ignoring the curvature, would it be plausible to add a new differential which covers pressurised stock?
 

Railperf

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Ignoring the curvature, would it be plausible to add a new differential which covers pressurised stock?
Of course it could. Italian main line tracks have PSR boards with three sets of numbers covering three classes of train. A fourth classification for tilting trains exists but the speeds are only found in the Italian version of their sectional Appendix 'fascicolo linea' ...and in the working timetable 'scheda treno' which displays linespeeds for the train plus any recommended limits.
 

Railperf

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It could but I doubt Network Rail would like to or would
They do indeed! In this country we have multiple classifications - MU, DMU, EMU /E , HST, EPS etc etc - which apply to various combinations of EMU/DMU Classes.

The EPS limits have are also unit specific, where Class 390's have one limit, while 221's can be 5, 10, 15mph lower. Crazy as it is, that is the situation.
So why not another variant?

In East Anglia for example, the 80/90 DMU limit from Maryland to Shenfield has the followng additional instruction in the sectional appendix:

trains formed of the following classes may travel at the higher emu/dmu speed: Class 321/322/345/360/379 720 and 745 EMU's, 755 bi-mode and Class 90 electric loco hauling/propelling mark 111 stock.

interestingly Class 317's not permitted!

In Italy, there are no TASS beacons as far as I can tell - probably due to the fact that rolling stock clearances are much greater. I do recall being on a CLass 485 unit where the buffet car was clearly not tilting due to some sort of failure - but we were still maintaining the higher 'P' pendolino limits. It was a lively ride to say the least in that carriage.

Could TASS beacons be fitted to Class 397's and Avanti Class 80X to monitor for overspeed - even if there is no tilt system to manage?
 
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The Planner

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They do indeed! In this country we have multiple classifications - MU, DMU, EMU /E , HST, EPS etc etc - which apply to various combinations of EMU/DMU Classes.

The EPS limits have are also unit specific, where Class 390's have one limit, while 221's can be 5, 10, 15mph lower. Crazy as it is, that is the situation.
So why not another variant?

In East Anglia for example, the 80/90 DMU limit from Maryland to Shenfield has the followng additional instruction in the sectional appendix:

trains formed of the following classes may travel at the higher emu/dmu speed: Class 321/322/345/360/379 720 and 745 EMU's, 755 bi-mode and Class 90 electric loco hauling/propelling mark 111 stock.

interestingly Class 317's not permitted!
Standards don't allow for more than three signed differentials as far as I am aware.
 

Railperf

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Standards don't allow for more than three signed differentials as far as I am aware.
Can we have an EPS/non EPS and one other - say HST+ which would cover pressure sealed stock able to run at higher than non EPS?
Or does the 90/EPS115/125 at Linslade count as three posted limits?
In that case an extra instruction in the sectional appendix could state that the lower EPS limit applies to Classes......

Or you post new 90/EHST 110/EPS 125 and reduce the Class 221 Voyager limits to EHST speeds? Assuming that non tilt stock could be allowed 110mph. Lower or higher as necessary.
Either way the Class 221's are being phased out and the difference between Class 221 tilt, and a new higher non EPS limit COULD be relatively minor.
 
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LNW-GW Joint

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Standards don't allow for more than three signed differentials as far as I am aware.

I assume that the change being sought will be for MU speeds to replace the lower EPS one (ie tilting 221).
Whoever gets the 221s won't want to use the WCML in tilt mode.
So we'd be back to 3 differential speeds, PS/MU/EPS (though the transition period, when both 80x and 221 were in service, would be interesting)
It probably then depends on the definition of "MU", eg loco hauled stock would still have to stick to PS limits.

Either way, there are likely to be more (maybe a lot more) speed signs needed, as the MU non-tilt speed profile will have to deal with places like Wolverton, Rugby, Lichfield, Rugeley and Whitmore, which I think are simply signed 110/EPS125 today over quite long stretches.
I also don't understand the TASS implications, which is currently mandatory over 110mph.
 

Railperf

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I assume that the change being sought will be for MU speeds to replace the lower EPS one (ie tilting 221).
Whoever gets the 221s won't want to use the WCML in tilt mode.
So we'd be back to 3 differential speeds, PS/MU/EPS (though the transition period, when both 80x and 221 were in service, would be interesting)
It probably then depends on the definition of "MU", eg loco hauled stock would still have to stick to PS limits.

Either way, there are likely to be more (maybe a lot more) speed signs needed, as the MU non-tilt speed profile will have to deal with places like Wolverton, Rugby, Lichfield, Rugeley and Whitmore, which I think are simply signed 110/EPS125 today over quite long stretches.
I also don't understand the TASS implications, which is currently mandatory over 110mph.
Yes but MU covers Class 350's which are not pressure sealed! It could be simply that Class 80x could be defined as being able to run at the lower EPS limit -changed to suit Class 80X capabilities - which could likely be lower than Class 221 speeds, but higher than the standard PSR. Class 80x will accelerate quicker from 100 or 110mph to 125mph than a Class 221 Voyager from 115mph to 125mph.
But clearly in places where only a single EPS figure is posted, some additional lower EPS limits might therefore need to be posted!

And isn't TASS only applicable to tilting stock? Nevertheless the Speed supervision could still be handy on 397's and 80x - provided the cost of equipping them is not too prohibitive. In eithercase aren't they supposed to be ETCS 'ready" - where TASS uses the EURO Balise designed for ETCS?
 

HSTEd

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Standards don't allow for more than three signed differentials as far as I am aware.

Essentially we can't do anything about this until ETCS arrives - at which point the number of things on a lineside speed sign is no longer a constraint
 

hwl

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Ignoring the curvature, would it be plausible to add a new differential which covers pressurised stock?
How to you guarantee that non pressurised stock isn't on the other track in the "middle"* tunnel going in the other direction?

That is the fundamental problem! ... to which an ETCS based solution is only likely one.

*With the UF and DS in
 

Bald Rick

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I see I have led the thread down a certain route with respect to pressure sealed trains. That was just one example.

There’s lots of other factors of course. Another example is passenger comfort. If the ‘MU’ speed is proposed to be lifted for the new Hitachi trains requiring increased cant deficiency (which means a more lively ride for passengers), other operators that have MU stock may not be willing to subject their passengers to the excitement, and therefore not agree to the increase.

Three differentials on the ground is the most that can be signed, and one of those must be the base that all trains can safely run at. I other words, ETCS is the answer, IF the Hitcai trains are to have a different speed profile to the three in existence.

Of course, that’s not going to happen. What will happen is that the passenger train speed (non EPS) will be lifted in those places where it is straightforward to do so.
 

hexagon789

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They do indeed! In this country we have multiple classifications - MU, DMU, EMU /E , HST, EPS etc etc - which apply to various combinations of EMU/DMU Classes.

The EPS limits have are also unit specific, where Class 390's have one limit, while 221's can be 5, 10, 15mph lower. Crazy as it is, that is the situation.
So why not another variant?

In East Anglia for example, the 80/90 DMU limit from Maryland to Shenfield has the followng additional instruction in the sectional appendix:

trains formed of the following classes may travel at the higher emu/dmu speed: Class 321/322/345/360/379 720 and 745 EMU's, 755 bi-mode and Class 90 electric loco hauling/propelling mark 111 stock.

interestingly Class 317's not permitted!

In Italy, there are no TASS beacons as far as I can tell - probably due to the fact that rolling stock clearances are much greater. I do recall being on a CLass 485 unit where the buffet car was clearly not tilting due to some sort of failure - but we were still maintaining the higher 'P' pendolino limits. It was a lively ride to say the least in that carriage.

Could TASS beacons be fitted to Class 397's and Avanti Class 80X to monitor for overspeed - even if there is no tilt system to manage?

There may be several different differential speeds but I meant that I don't believe Network Rail would want to add another, posts by other members previously in sone infrastructure related threads rather suggested NR prefer to use as few of them as possible generally.
 

Bald Rick

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There may be several different differential speeds but I meant that I don't believe Network Rail would want to add another, posts by other members previously in sone infrastructure related threads rather suggested NR prefer to use as few of them as possible generally.

It’s not about preference, but about group standards. Too many signs increase the chance of driver error. Having restrictions for specific rolling stock unsigned but only in the sectional appendix or other instructions even more so.
 

hexagon789

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It’s not about preference, but about group standards. Too many signs increase the chance of driver error. Having restrictions for specific rolling stock unsigned but only in the sectional appendix or other instructions even more so.

I can completely understand that, I marvel at how much drivers are expected to remember and unnecessarily increasing that is if course to be avoided if possible.
 

Bald Rick

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I can completely understand that, I marvel at how much drivers are expected to remember and unnecessarily increasing that is if course to be avoided if possible.

To put it into perspective. Let’s say Ledburn curves can’t have its non EPS speed increased, but the speed for the Hitachi trains can be increased from 90-100mph. This can’t be signed, so is covered by a special instruction.

On Monday - Thursday driver Jones drives the 0907 Pendolino to Liverpool, and passes through at 125mph. On Friday, Jonesy is rostered the 0910 to Chester, a Hitachi train. He forgets he’s on a Hitachi and takes Ledburn at 125mph. Unfortunately, a passenger just leaving the toilet gets thrown against the vestibule bulkhead, enough to break some bones. Another passenger carrying 4 hot coffees throws them all over a family of four including two young kids who get scalded.

Who gets to sit in the dock in court?
 

hexagon789

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To put it into perspective. Let’s say Ledburn curves can’t have its non EPS speed increased, but the speed for the Hitachi trains can be increased from 90-100mph. This can’t be signed, so is covered by a special instruction.

On Monday - Thursday driver Jones drives the 0907 Pendolino to Liverpool, and passes through at 125mph. On Friday, Jonesy is rostered the 0910 to Chester, a Hitachi train. He forgets he’s on a Hitachi and takes Ledburn at 125mph. Unfortunately, a passenger just leaving the toilet gets thrown against the vestibule bulkhead, enough to break some bones. Another passenger carrying 4 hot coffees throws them all over a family of four including two young kids who get scalded.

Who gets to sit in the dock in court?

I can understand the potential problem. As I understood it though, the new non-tilt speeds wouldn't be Hitachi specific rather ordinary non-EPS speeds would be raised where possible.

I can see you reasoning though adding to the case against introducing another speed differential category though, but I really don't see Network Rail creating one purely for pressure-sealed non-tilt trains that couldn't be signed.

The tunnel on the SWML with a restriction for 442s and HSTs due to pressure blowback was as I recall signed with an HST differential which on the Southern Region 442s were permitted to use, so no confusion with that one.
 

Bald Rick

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I can understand the potential problem. As I understood it though, the new non-tilt speeds wouldn't be Hitachi specific rather ordinary non-EPS speeds would be raised where possible.

It’s the only way it can be done, my example was intended to help others reach that conclusion.

My point is that if the non-EPS speed is to be lifted, then it has to be capable for all passenger trains, and not just the Hitachi. And that brings signal sighting into the equation. It’s all good fun!
 

Taunton

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Although south of Rugby it's irrelevant anyway. The non-EPS trains are largely fitted into the timetable in capacity that is 'wasted' for other reasons - e.g. the xx15 LNW path uses the path lost by the xx10 calling at Milton Keynes, etc.
It arises significantly elsewhere. The Watford Junction stops were mostly lost because of "capacity" (to run three instead of two times an hour to Birmingham, for example, an overprovision which can result in some such services wholly under the wire being formed of 5-car Voyagers). It completely disabled the service being of much value to the onetime high fare payers from Hertfordshire and Bucks, to the extent that when I wanted to travel from Watford to Carlisle the most effective routing was to go up to Euston and come back down again.
 

hexagon789

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My point is that if the non-EPS speed is to be lifted, then it has to be capable for all passenger trains, and not just the Hitachi. And that brings signal sighting into the equation.

Ignoring any consideration of pressure-sealing, if an 805/807 (or whatever it is) can be passed for 115 on an 110/EPS 125 section is there any reason that a Class 220 Voyager couldn't run at 115, obviously there are many variables regarding why a speed limit is what it is but the braking capacity of even a loco-hauled IC225 meets the W125 curve which I assume is what trains have to meet on the WCML for higher-speed operations regardless if the more modern trains with fully electrically actuated brakes can pull up well inside the curve.
 

Bald Rick

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Ignoring any consideration of pressure-sealing, if an 805/807 (or whatever it is) can be passed for 115 on an 110/EPS 125 section is there any reason that a Class 220 Voyager couldn't run at 115

Probably. But possibly not. It would need checking.
 

LNW-GW Joint

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Ignoring any consideration of pressure-sealing, if an 805/807 (or whatever it is) can be passed for 115 on an 110/EPS 125 section is there any reason that a Class 220 Voyager couldn't run at 115, obviously there are many variables regarding why a speed limit is what it is but the braking capacity of even a loco-hauled IC225 meets the W125 curve which I assume is what trains have to meet on the WCML for higher-speed operations regardless if the more modern trains with fully electrically actuated brakes can pull up well inside the curve.

There isn't a requirement for 220s (or 222s/180s/HSTs) to run on the WCML at 125mph.
Avanti (and TPE north of Preston) are the only users for the forseeable future.
Non-pressure-sealed stock (eg 350s) will not be operating above 110mph, nor will 730s.
221s will be gone.
NR really only has to deal with 80x and 397, and the future HS2 stock when it is known.
 

CW2

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One thing that gets overlooked when considering adding to the lineside speed signs is that you need to find somewhere to place the sign where it will be visible for long enough to be read by the driver. The more signs you have, the longer the reading time, as the driver needs to see the signs and then work out which one applies to him / her. The restricted loading gauge means that on 4-track sections it can be very difficult to find a site for signs, especially between the middle pair of lines. Ultimately ETCS is the answer, with in-cab signalling doing away with all lineside speed signs. Until then, it's a compromise.
 

LNW-GW Joint

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One thing that gets overlooked when considering adding to the lineside speed signs is that you need to find somewhere to place the sign where it will be visible for long enough to be read by the driver. The more signs you have, the longer the reading time, as the driver needs to see the signs and then work out which one applies to him / her. The restricted loading gauge means that on 4-track sections it can be very difficult to find a site for signs, especially between the middle pair of lines. Ultimately ETCS is the answer, with in-cab signalling doing away with all lineside speed signs. Until then, it's a compromise.

Which (I think) is why TASS is important at higher speeds, on curving track.
 

Bald Rick

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Which (I think) is why TASS is important at higher speeds, on curving track.

Partly, but the main reason for TASS is in the first letter of the acronymn. The key functionality is to stop the train going over the non-tilt speed if the tilt isn’t working. Drivers are still expected to know and use the lineside signage.
 

The Planner

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One thing that gets overlooked when considering adding to the lineside speed signs is that you need to find somewhere to place the sign where it will be visible for long enough to be read by the driver. The more signs you have, the longer the reading time, as the driver needs to see the signs and then work out which one applies to him / her. The restricted loading gauge means that on 4-track sections it can be very difficult to find a site for signs, especially between the middle pair of lines. Ultimately ETCS is the answer, with in-cab signalling doing away with all lineside speed signs. Until then, it's a compromise.
It is causing problems at a couple of locations with the Avanti led work too.
 

James James

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It's just the typical British thing that everything has to be a headache and cheaper but not the case in Europe or countries like Japan.
Errm that is exactly what is happening in Germany - they're not wanting any tilt in future.
And in Switzerland, the decision to go for tilt on one line has caused a lot of argument, because... it was supposed to be the cheap way out (pay less for tilting on a new train - which isn't even proven to work yet - instead of building a newer straighter line for the problematic segment). No one knows if this will even work out. And they're also removing tilt when possible - e.g. with the new Gotthard route. That said there's still some future for tilt due to decentralisation and therefore needing to maintain more IC style lines, which might only be possible with tilt (e.g. Jura routes).
Poland didn't bother with Tilt on their so-called Pendolinos.
Plenty of other countries where they're just building new straight routes instead of trying to make do using tilt.

(Japan's a bit special in any case.)
 

LNW-GW Joint

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Errm that is exactly what is happening in Germany - they're not wanting any tilt in future.

DB/OeBB use tilt on Vienna-Frankfurt (from Wels into Germany via Passau), using ICE-T sets.
Tilt stock is also due to be used on EC services on the newly electrified route in Bavaria between Munich and Zurich.
 

RailWonderer

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Eliminating tilt by ordering the 805s and 807s has opened a can of worms it seems. I can understand wanting to lower maintennance costs but is that cost saving worth the headache of drivers forgetting EPS speeds, many lineside signs to read, and passenger comfort falling by juggling coffees and trying not to spill them onto a family of small children?
 

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