Network Rail and Chiltern Railways apply for train protection (ATP) exemption

[XCTurbostar]

https://www.railadvent.co.uk/2020/0...apply-for-train-protection-exemption.html?amp

Network Rail and Chiltern Railways have applied to the Office of Rail and Road for exemption from the law requiring the provision of automatic train protection.

The application relates to specific Chiltern Railway trains operating south of Aynho Junction.

A consultation has been launched by the ORR to invite the public to express their views on the application.

The application is looking to allow the current Automatic Train Protection system to be used until 30th June 2024.

The existing equipment on some trains will stop operating when disconnected.

The TPWS (Train Protection Warning System) equipment will be upgraded to ‘enhanced TPWS’ with the system operating on all relevant trains by 31st December 2027.

The Railway Safety Regulations 1999 require operators to only permit train operations with protection equipment fitted. This equipment can stop a train if it passes a red signal.

Where it is practicable to use ATP, this must be used, but the ORR may grant an exemption.

A version of ATP is fitted to a number of routes operated by Chiltern Railways south of Aynho Junction. This equipment is now becoming obsolete, and cant be replaced.

Chiltern Railways and Network Rail are proposing to continue relying on TPWS equipment which also protects trains from passing red signals but without the full prevention functionality of ATP systems. Its ‘enhancement’ will increase the locations where this system is in operation.

Thoughts?

 

[Belperpete]

I am a bit puzzled by what is going to happen between 2024 and 2027, if the current ATP is only going to be used until 2024, but enhanced TPWS is only going to be fitted by 2027. And what exactly do they mean by "enhanced TPWS"? Do they mean that they will be fitting the TPWS in more situations than it would normally be fitted, such as automatic signals?

 

[MarkyT]

I am a bit puzzled by what is going to happen between 2024 and 2027, if the current ATP is only going to be used until 2024, but enhanced TPWS is only going to be fitted by 2027. And what exactly do they mean by "enhanced TPWS"? Do they mean that they will be fitting the TPWS in more situations than it would normally be fitted, such as automatic signals?

I would have thought that would be the case, as ATP is at all signals today. Surprised it needs to take that long though as it should be a fairly simple repetitive task and there aren't huge numbers of signals involved, getting quite sparse with 2 aspect sections at the outer reaches. Why should one line take longer than the entire national programme did?

 

[Belperpete]

I would have thought that would be the case, as ATP is at all signals today. Surprised it needs to take that long though as it should be a fairly simple repetitive task and there aren't huge numbers of signals involved, getting quite sparse with 2 aspect sections at the outer reaches. Why should one line take longer than the entire national programme did?

Might they also have to fit TPWS protection to more speed restrictions than would usually be the case, to mirror ATP?

The national fitment programme used a TPWS retrofit method, that didn't require any additional interlocking interfaces trackside. If they can't use this method, then this could involve significant work if additional trackside modules are required to control and monitor the additional TPWS. In which case, it might be better to just get permission to use the retrofit method. This might not be possible, however, if it would be incompatible with the existing TPWS there today.

 

[hexagon789]

Might they also have to fit TPWS protection to more speed restrictions than would usually be the case, to mirror ATP?

The national fitment programme used a TPWS retrofit method, that didn't require any additional interlocking interfaces trackside. If they can't use this method, then this could involve significant work if additional trackside modules are required to control and monitor the additional TPWS. In which case, it might be better to just get permission to use the retrofit method. This might not be possible, however, if it would be incompatible with the existing TPWS there today.

I read it as meaning a far more comprehensive application of TPWS, perhaps even to the point of covering all Permanent Speed Restrictions even where the drop in speed is relatively minor.

 

[mr_jrt]

Just for my own education, roughly how much harder/expensive would it be to fit ETCS-2?

 

[bengley]

Just for my own education, roughly how much harder/expensive would it be to fit ETCS-2?

Compared to fitting a few extra TPWS grids, significantly/significantly.

 

[Domh245]

Not least as none of the rolling stock is ETCS fitted or ready, bar the Cl 68s. All Chiltern stock is TPWS fitted that I'm aware of

 

[MarkyT]

Might they also have to fit TPWS protection to more speed restrictions than would usually be the case, to mirror ATP? The national fitment programme used a TPWS retrofit method, that didn't require any additional interlocking interfaces trackside. If they can't use this method, then this could involve significant work if additional trackside modules are required to control and monitor the additional TPWS. In which case, it might be better to just get permission to use the retrofit method. This might not be possible, however, if it would be incompatible with the existing TPWS there today.

ISTR the main differences being:
1. Separate monitoring of TPWS status and lamp proving which can be combined in retrofit. Same result - if either fail, the signal to rear will not clear, and a tech needs to go out to the site to investigate, although the signaller doesn't know which has failed so that will alter verbal instruction given to driver to pass at red. Wouldn't want to mix methods on a particular panel or workstation. Maybe there are some status inputs from the ATP that might be reused for separate TPWS monitoring. I don't recall anything like that though as, unlike TPWS, Selcab ATP is supposedly intrinsically failsafe so doesn't need proving in signal to rear.
2. Possibly separate outputs from SSI to drive the TPWS units. Can be wired in parallel with lamp drive outputs in retrofit. Again no functional difference.

I read it as meaning a far more comprehensive application of TPWS, perhaps even to the point of covering all Permanent Speed Restrictions even where the drop in speed is relatively minor.

Well they're the easiest, on plain line at least, not requiring any interlocking interface (or will they require proving in signal to rear?), although clearly they need a power supply. If they're going to attempt to supervise junction speeds, that's a whole new level of complexity.

I'd say if they're going for a comprehensive replication of most of the current ATP functionality, an ETCS overlay would be more practical, assuming the trains were ready for that by then, but I wonder if the units will require that anyway in order to emulate Seltrac on the shared LUL Metropolitan sections. Might be a test-bed for a hybrid L1 scheme perhaps.

 

[Belperpete]

You would probably need to fit all the trackside ETCS kit first, before you started converting the rolling stock, as I doubt that you could retrofit ETCS onto the existing rolling-stock in addition to the existing ATP.

Thinking about this further, wasn't the Chiltern lines ATP (like the GW system) just an off-the-peg European system? Has it all been replaced by something else in all the other places it was used?

 

[MarkyT]

Just for my own education, roughly how much harder/expensive would it be to fit ETCS-2?

Full level 2 signals away, probably very, and there's the rolling stock to consider. It may be neccessary to have ETCS on the trains anyway by then for Seltrac emulation on the LUL shared section, unless they're going to retain mechanical train-stops just for the Chiltern trains. There is a hybrid signals-retained L2 ETCS system being rolled out on GWML at the moment for Heathrow Express and Crossrail, so that could provide a reference. I not from this description that as well as RBCs (radio block centres) for movement authorities, the system includes 1000 Programmed Balises (Fixed and Switchable) so that implies at least some local interface to lineside signalling, a possible method for Chiltern?

The RailStaff Awards 2024

The RailStaff Awards started in 2007 with an aim to show recognition of the great work of the people who work in the rail industry.

www.railstaffawards.com

“GWML ETCS Project is the introduction of European Train Control System (ETCS) Level 2 overlay from Paddington Station at 0m to 12m along the Great Western Mainline, including the Heathrow Branch. This programme of works is the first ETCS deployment across a mainline railway and at a terminus station. Network Rail, responsible for the provision of a continuous Automatic Train Protection solution, have chosen ETCS in readiness for the Crossrail Services operated by MTR using the Bombardier Class 345 Rolling Stock. The chosen product for this project is Alstom’s ATLAS Baseline 3 MR1 3.4.0.

 

[Belperpete]

ISTR the main differences being:
1. Separate monitoring of TPWS status and lamp proving which can be combined in retrofit. Same result - if either fail, the signal to rear will not clear, and a tech needs to go out to the site to investigate, although the signaller doesn't know which has failed so that will alter verbal instruction given to driver to pass at red. Wouldn't want to mix methods on a particular panel or workstation. Maybe there are some status inputs from the ATP that might be reused for separate TPWS monitoring. I don't recall anything like that though as, unlike TPWS, Selcab ATP is supposedly intrinsically failsafe so doesn't need proving in signal to rear.
2. Possibly separate outputs from SSI to drive the TPWS units. Can be wired in parallel with lamp drive outputs in retrofit. Again no functional difference.

Agreed, the control of the TPWS should be no problem, it is the indication and proving that are different. I believe that there is a ban on mixing the two methods in the same area.

If I recall correctly, the TPWS for speed-restrictions does need to be monitored in case it fails, but it does not need to be proved in signal aspects.

 

[MarkyT]

You would probably need to fit all the trackside ETCS kit first, before you started converting the rolling stock, as I doubt that you could retrofit ETCS onto the existing rolling-stock in addition to the existing ATP.

Thinking about this further, wasn't the Chiltern lines ATP (like the GW system) just an off-the-peg European system? Has it all been replaced by something else in all the other places it was used?

Selcab on Chiltern is functionally equivalent to German LZB on board but with simplified distributed trackside infrastructure, and it bears a resemblance to Seltrac, originally from the same manufacturer Standard Elektrik Lorenz (SEL), with its lengths of periodically transposed wire between the rails for failsafe track-train comms, just not laid continuously like original Seltrac. It's a discontinued product now but presumably if you paid them enough it could be supported in theory by Thales who own Seltrac now, although that system has changed considerably and they offer a beacon (i.e. balise) and radio approach for new installations. So component parts are probably no longer available and any notional continued 'support' beyond their initial term would most likely mean complete replacement with their latest proprietary system version again on both track and trains, exactly the bind that ETCS is supposed to release railway authorities from.

Here's something interesting about Selcab by someone involved in the train equipment testing

Chiltern Lines ATP

Chiltern Line ATP Pilot Scheme
During the delivery of the new Class 165 DMUs to Aylesbury depot in 1990, for use on the lines between Marylebone, Aylesbury and Bicester, the Alcatel SEL system was fitted to the class 165 fleet and was being put through its paces by GEC Alstom Signalling Ltd (GASL). Alcatel SEL of Stuttgart, Germany had already designed and installed the successful LZB continuous loop system in use in Germany. The system in UK was a development of this and eventually became known as Selcab®. This system is installed in a number of locations around Europe, notably at each end of the standard gauge high speed AVE line between Madrid and Seville in Spain in addition to LZB on the main route.

The system on GW was a development of the TBL1 system used on Belgian railways and developed by former Belgian conglomerate ACEC, the rail business parts of which were eventually absorbed into Alstom. The UK implementation, although using the same track equipment, was far more sophisticated than in Belgium however, which merely implemented a simple distant warning and trainstop function. Infrabel finished removing their system nearly a decade ago, replacing it with a Eurobalise based alternative and expanding fitment to nearly every signal in the country that was not already fitted with ETCS L2 or one of their other protection systems. There is one other installation of the ACEC equipment, on the East Rail Line in Hong Kong which uses the transponders for an AWS like function. That is due to be phased out in 2020, leaving the GWML as the only location remaining in the world.

Also from the train testing guy, something about the GWML system

Great Western Main Line ATP

Great Western Main Line ATP Pilot Scheme
During 1989 and 1990, 89 HST power cars were fitted with the Belgian ACEC TBL Automatic Train Protection (ATP) system at Landore depot, Swansea. Initially running out of Bristol St Phillips Marsh (SPM) depot the HST trials on GWML eventually settled into a pattern of running between Swindon and Bristol Parkway (Stoke Gifford) on the Badminton Line. This was the first part of the route to be fully fitted with the ATP lineside equipment.

 

[hexagon789]

ISTR the main differences being:
1. Separate monitoring of TPWS status and lamp proving which can be combined in retrofit. Same result - if either fail, the signal to rear will not clear, and a tech needs to go out to the site to investigate, although the signaller doesn't know which has failed so that will alter verbal instruction given to driver to pass at red. Wouldn't want to mix methods on a particular panel or workstation. Maybe there are some status inputs from the ATP that might be reused for separate TPWS monitoring. I don't recall anything like that though as, unlike TPWS, Selcab ATP is supposedly intrinsically failsafe so doesn't need proving in signal to rear.
2. Possibly separate outputs from SSI to drive the TPWS units. Can be wired in parallel with lamp drive outputs in retrofit. Again no functional difference.

Well they're the easiest, on plain line at least, not requiring any interlocking interface (or will they require proving in signal to rear?), although clearly they need a power supply. If they're going to attempt to supervise junction speeds, that's a whole new level of complexity.

I'd say if they're going for a comprehensive replication of most of the current ATP functionality, an ETCS overlay would be more practical, assuming the trains were ready for that by then, but I wonder if the units will require that anyway in order to emulate Seltrac on the shared LUL Metropolitan sections. Might be a test-bed for a hybrid L1 scheme perhaps.

ECTS surely would be more practical, as well as arguably more future proof given that's what the network is working towards.

 

[popeter45]

ECTS surely would be more practical, as well as arguably more future proof given that's what the network is working towards.

ECTS and the need to Electrify in the next 20 years makes me wonder if these plus new rolling stock should be bundled together as a Chrilterns Modernisation program like what happened with th GWML (hopefully with far fewer cutbacks)
Order some Aventra with a sub fleet AC/DC capable units that can also run on Aylesbury branch

 

[CyrusWuff]

The consultation and supporting documents can be found on the ORR website: https://orr.gov.uk/rail/consultatio...ain-protection-duties-chiltern-railway-routes

The short version is that Thales declared they would no longer support SELCAB after 31st December 2012, so Network Rail and Chiltern bought up as many spares as they could at that point, which should have lasted until 2018.

The proposal at hand is to install TPWS at every signal between Marylebone and Aynho Junction and upgrade the on-board equipment from TPWS Mk1 to TPWS Mk4 (the Class 68s and 168/3s are already fitted with same).

At the same time, they're applying for an exemption under Railway Safety Regulations to permit trains without functional ATP to remain in passenger service (assuming the AWS and TPWS is functional of course).

 

[MarkyT]

ECTS surely would be more practical, as well as arguably more future proof given that's what the network is working towards.

I think so too and it's interesting that the GWML overlay is using Baseline 3 MR1 which allows for limited supervision techniques, possibly appropriate for an ATP replacement on Chiltern as well as GWML. It's all down to whether the trains can be fitted in time, or at all, or a suitable rolling stock replacement could be arranged. There's also the issue with the LUL Four Lines Seltrac system to consider on the shared section of the Aylesbury line. A moden ETCS train ought to be able to emulate Seltrac onboard using standard techniques, but its also plausible the new signalling could also incorporate 1909 technology mechanical train-stop arms for fixed block working of the Chiltern trains! Thinking right outside the box, that might also be an option worth considering for the Network Rail parts of the infrastructure. At least its intrinsically failsafe!

 

[ForTheLoveOf]

So what is the proposal for ensuring that the current level of safety is not eroded between the point they allow ATP-fitted trains without working ATP to run, and the point the new TPWS+ system is fully commissioned?

Seems extraordinarily short sighted to be planning to invest millions into new TPWS fitments by 2027 - at which point TPWS will already be 30 years old in its UK application. Especially given the whole reason d'être is that its "outdated" predecessor stopped having spares supplied 22 years after installation... And the fact that you are paying to get less safety at the end of the day!

Why is the same money not being put towards ETCS instead? It will be needed sooner or later anyway!

 

[mr_jrt]

Guess the hope is ECTS will be cheaper by the time comes to roll it out on the Chiltern line? Otherwise you'd think given current interest rates it would be the sort of thing borrowing was invented for, assuming the resource was available to design and fit it of course. I suspect they will be more than a little busy on other areas though.

 

[philthetube]

Where does this leave Amersham to Harrow, assuming resignalling does not happen in time. There are speed restrictions on that stretch which presumably would need protection?

 

[The Planner]

The signalling is a long way from life expired on the Chilterns remember, I suspect that has a large part to do with it.

 

[Anthony061]

My understanding of the consultation documents is that Enhanced TPWS is to be fitted by 2024 and is currently expected to operate until 2027 when a national ETCS roll-out strategy should have been developed (ECML currently being fitted). As the 1999 Railway Safety Regulations effectively dictates the use of ATP, there is a need for an exemption. The other exemption to 2024 is so that should the ATP fail before Enhanced TPWS is fitted (i.e. both trackside and Mk4 in cab) then trains can run so long as existing TPWS is operative.

So what is the proposal for ensuring that the current level of safety is not eroded between the point they allow ATP-fitted trains without working ATP to run, and the point the new TPWS+ system is fully commissioned?

The argument is based on railways being relatively safer than roads. Withdrawing stock due to non-functioning ATP would cause overcrowding, transferring passengers on to the road network and resulting in an increase of overall risk of the transport system relative to losing a degree of safety from not using ATP.

 

[alxndr]

Interesting that they’re taking this route for the Chilterns when I’ve heard rumour of some of the equipment for the western version being reverse engineered due to a shortage of spares.

 

[Belperpete]

Interesting that they’re taking this route for the Chilterns when I’ve heard rumour of some of the equipment for the western version being reverse engineered due to a shortage of spares.

The Chilterns must surely be toward the top of any ETCS fitments programme? In which case, it makes sense not to spend a lot of money keeping the existing ATP going.

 

[hexagon789]

I think so too and it's interesting that the GWML overlay is using Baseline 3 MR1 which allows for limited supervision techniques, possibly appropriate for an ATP replacement on Chiltern as well as GWML. It's all down to whether the trains can be fitted in time, or at all, or a suitable rolling stock replacement could be arranged. There's also the issue with the LUL Four Lines Seltrac system to consider on the shared section of the Aylesbury line. A moden ETCS train ought to be able to emulate Seltrac onboard using standard techniques, but its also plausible the new signalling could also incorporate 1909 technology mechanical train-stop arms for fixed block working of the Chiltern trains! Thinking right outside the box, that might also be an option worth considering for the Network Rail parts of the infrastructure. At least its intrinsically failsafe!

That's also one of the advantages is that ETCS can be modified to suit local requirements. Given the Chiltern ATP is apparently life-expired surely the similarly aged GWML one must be as well unless the system employed is less obsolete than the Chilterns one

 

[hexagon789]

ECTS and the need to Electrify in the next 20 years makes me wonder if these plus new rolling stock should be bundled together as a Chrilterns Modernisation program like what happened with th GWML (hopefully with far fewer cutbacks)
Order some Aventra with a sub fleet AC/DC capable units that can also run on Aylesbury branch

It would certainly solve a lot of things in one go as well as future proofing the route for some time to come.

 

[ForTheLoveOf]

The signalling is a long way from life expired on the Chilterns remember, I suspect that has a large part to do with it.

But the signalling system apparently cannot continue as it is. So the choice is throwing good money after bad (locking the Chiltern lines into lights on sticks for probably another 20 years, making capacity improvements more expensive and thus difficult to justify) or accepting that the signalling isn't life expired but this is the right moment to replace it with ETCS as part of a Total Route Modernisation mk2 (or 3 depending on if you count the Evergreen projects).

 

[The Planner]

But the signalling system apparently cannot continue as it is. So the choice is throwing good money after bad (locking the Chiltern lines into lights on sticks for probably another 20 years, making capacity improvements more expensive and thus difficult to justify) or accepting that the signalling isn't life expired but this is the right moment to replace it with ETCS as part of a Total Route Modernisation mk2 (or 3 depending on if you count the Evergreen projects).

The lights on sticks can continue, the ATP cannot. Outside the proposals for trains to OOC, I really cannot see a lot happening on the Chilterns for the forseeable. You have a 3 minute headway Marylebone to Risborough anyway and ETCS is unlikely to make substantial improvements to that, if any at all.

 

[ForTheLoveOf]

The lights on sticks can continue, the ATP cannot. Outside the proposals for trains to OOC, I really cannot see a lot happening on the Chilterns for the forseeable. You have a 3 minute headway Marylebone to Risborough anyway and ETCS is unlikely to make substantial improvements to that, if any at all.

Is the current signalling compatible with 25kV, and if not, how many millions will it cost to make it compatible?

 

[Belperpete]

Is the current signalling compatible with 25kV, and if not, how many millions will it cost to make it compatible?

I think the interlocking on most of the route is SSI, so should be 25kv compatible at minimum cost. Things like point machines and track circuits might need changing, but that would not likely be a significant cost. It wouldn't surprise me if it were done to electrification standards in the first place, considering how much electrification is in the vicinity in the London area.