Welshpool crossing crash (22/06/20)

[Belperpete]

For ETCS/ERTMS, you require trackside balises and an on-board odometry system that calculates where the train is between balises. For an enhanced GPS-based system, you still need the on-board odometry system to validate the GPS positioning, and you still need some trackside balises to work out which track the train is on in multi-track areas. So what is the saving? OK, it wouldn't need nearly so many trackside balises, but they are not "expensive trackside infrastructure" - they are simple, cheap and largely maintenance-free. It looks to me like the solution is more expensive and more complex than the "problem" it is trying to solve.

 

[edwin_m]

A system such as bus operators use, which reports a GPS position back to a controller by radio every few seconds, is standard technology that can be, and probably has been, fitted to trains very easily. There is no interface to any on-train system other than needing a power supply. The problem, as mentioned above, is that those systems are reliable enough for routine applications such as monitoring punctuality and working information systems, but not to be used as the basis of what might be a life-or-death decision such as whether a train has passed a crossing or not.

 

[philthetube]

The problem with relying on gps is finding a solution for if Donald Trump switches it off!!!!!!!!!!

 

[GB]

The problem with relying on gps is finding a solution for if Donald Trump switches it off!!!!!!!!!!

That won't happen anymore than he would launch nuclear missiles off his own back.

 

[gsnedders]

The problem with relying on gps is finding a solution for if Donald Trump switches it off!!!!!!!!!!

The odds of GPS and Galileo and GLONASS all getting turned off simultaneously is really low. If we end up in a state where they are, we're almost certainly in a much worse place (i.e., WW3).

 

[InOban]

The US tried switching it off at the start of the first Iraq war. But all the tank crews had bought hand helds and were using them to find their way in the desert.

 

[Taunton]

An enhanced GPS-based system of locating trains precisely would have many benefits to the railway, not just in the UWC area. RSSB did a lot of work on this about five or six years ago.

It's a shame. The railway was long in the forefront on comms, right back in history. First with the telegraph, even before there was a public service. First with teleprinters back in the 1920s. Etc. Nobody said don't put telegraph wires along the line because they're not cost-effective. But steadily it was caught up, then overtaken, by the rest of the world. Now, with the old innovative spirit gone and developments taking years if not decades to implement it just seems things have fallen way behind.

Maybe we should get Space-X to take over management of technological development.

 

[Dunfanaghy Rd]

A system such as bus operators use, which reports a GPS position back to a controller by radio every few seconds, is standard technology that can be, and probably has been, fitted to trains very easily. There is no interface to any on-train system other than needing a power supply. The problem, as mentioned above, is that those systems are reliable enough for routine applications such as monitoring punctuality and working information systems, but not to be used as the basis of what might be a life-or-death decision such as whether a train has passed a crossing or not.

EWS fitted its engines with this. There is (was?) a program called TCMS which could display a train's progress. I remember the day when waiting for a train in So'ton Docks (TRUST was down), to find that my train was over the Dogger Bank! Bit of an OOPS moment.
Pat

 

[Belperpete]

It's a shame. The railway was long in the forefront on comms, right back in history. First with the telegraph, even before there was a public service. First with teleprinters back in the 1920s. Etc. Nobody said don't put telegraph wires along the line because they're not cost-effective. But steadily it was caught up, then overtaken, by the rest of the world. Now, with the old innovative spirit gone and developments taking years if not decades to implement it just seems things have fallen way behind.

Maybe we should get Space-X to take over management of technological development.

The innovative spirit was killed off by privatisation, with the killing-off of BR Research, with Railtrack deciding that any innovation and development work was the responsibility of the contractors, with the lack of any incentive to innovate, and the hurdles introduced to getting anything new accepted. From being one of the world leaders in railway technology, we are unfortunately reduced to accepting what others are developing.

 

[BayPaul]

Something I find difficult about the railway is it seems from an outsider's point of view that if there isn't a way to make a 100% reliable safety critical system, the preference seems to be to not have a system at all.

There have been too many accidents at UWCs recently, and they are not intuitive for the general public to use. It would not be too difficult or expensive to come up with a system using GPS and mobile phone technology that switches a green light to red at a crossing when a train is around 2 minutes away, or switches on a flashing red 'contact the signaller' light if it loses contact with the next train (or if that train's GPS says it is on the dogger bank) , but because this couldn't be made 100% accurate (even though in this case it would fail safe), the preference is to keep the current system, which isn't remotely fail safe, especially if the user doesn't need to phone back.

 

[ForTheLoveOf]

Something I find difficult about the railway is it seems from an outsider's point of view that if there isn't a way to make a 100% reliable safety critical system, the preference seems to be to not have a system at all.

There have been too many accidents at UWCs recently, and they are not intuitive for the general public to use. It would not be too difficult or expensive to come up with a system using GPS and mobile phone technology that switches a green light to red at a crossing when a train is around 2 minutes away, or switches on a flashing red 'contact the signaller' light if it loses contact with the next train (or if that train's GPS says it is on the dogger bank) , but because this couldn't be made 100% accurate (even though in this case it would fail safe), the preference is to keep the current system, which isn't remotely fail safe, especially if the user doesn't need to phone back.

This is so very true. The fact that UWCs are considered acceptable due to being grandfathered in seemingly means that anything that doesn't comply with modern safety and failsafe standards can't be implemented, even if safer than what is there already.

 

[6Gman]

Something I find difficult about the railway is it seems from an outsider's point of view that if there isn't a way to make a 100% reliable safety critical system, the preference seems to be to not have a system at all.

There have been too many accidents at UWCs recently, and they are not intuitive for the general public to use. It would not be too difficult or expensive to come up with a system using GPS and mobile phone technology that switches a green light to red at a crossing when a train is around 2 minutes away, or switches on a flashing red 'contact the signaller' light if it loses contact with the next train (or if that train's GPS says it is on the dogger bank) , but because this couldn't be made 100% accurate (even though in this case it would fail safe), the preference is to keep the current system, which isn't remotely fail safe, especially if the user doesn't need to phone back.

I assume it's a matter of cost. Some UWCs do have green/red lights for users (the one I occasionally use certainly does). Not sure that it's correct to say that "it would not be too difficult or expensive" to use the technology you cite in the way you suggest. And I would suggest that it is indeed intuitive to most people to read the signs, follow the procedure set out, open both gates before crossing, close them after use and not to park a vehicle on a railway line # .

# This is a general point about what some users do/ fail to do. It's not a specific reference to what happened in this case which will only emerge in due course.

 

[QueensCurve]

I find that last post surprising since both ships and, increasingly, aircraft use GPS at the core of their navigation.

I may be out of date on this, my understanding is that, for approaches to runways, when precision is needed in a GPS position, it is subject to correction by comparison with a ground-based GPS receiver at a known nearby location.

 

[Mcr Warrior]

Don't commercial aircraft land primarily using ILS (= Instrument Landing System) which essentially is a set of radio beams giving pilots vertical and horizontal guidance when on final approach?

 

[BayPaul]

I assume it's a matter of cost. Some UWCs do have green/red lights for users (the one I occasionally use certainly does). Not sure that it's correct to say that "it would not be too difficult or expensive" to use the technology you cite in the way you suggest. And I would suggest that it is indeed intuitive to most people to read the signs, follow the procedure set out, open both gates before crossing, close them after use and not to park a vehicle on a railway line # .

# This is a general point about what some users do/ fail to do. It's not a specific reference to what happened in this case which will only emerge in due course.

I would tend not to believe a sign that tells me to cross a live railway line 5 times, and doesn't tell me to phone back to say I've finished. I would (eventually) decide to follow it, but I think it's far from intuitive.

I must admit I was thinking more of simple pedestrian crossings for my mobile phone tech based system, though I think it would also have a place for UWCs. I still think it could be implemented quite cheaply, with a single standard piece of equipment, solar powered, at each crossing, connected by 4G to a national database of train locations, mainly fed from the signalling system, with a timer from the nearest signals in both directions, and not going green until the train has confirmed past the crossing, by signal, GPS or another method.

 

[6Gman]

I would tend not to believe a sign that tells me to cross a live railway line 5 times, and doesn't tell me to phone back to say I've finished. I would (eventually) decide to follow it, but I think it's far from intuitive.

How else can you cross?

1. To open the far gate
2. To return to the vehicle
3. To cross with the vehicle
4. To close the (now) far gate
5. To return to the vehicle

 

[BayPaul]

How else can you cross?

1. To open the far gate
2. To return to the vehicle
3. To cross with the vehicle
4. To close the (now) far gate
5. To return to the vehicle

But it isn't at all difficult to misunderstand and do 1 and 4 with the vehicle stopped between the 2 gates. You and I might not do it, but that would be the instinctive thing to do, as it would be the way you would open farm gates, for example.

 

[Mcr Warrior]

Surely the process should be...

1. Contact the signaller for permission to cross.
2. Open the near gate.
3. Cross on foot and open the far gate.
4. Return on foot to vehicle.
5. Drive vehicle over and park up somewhere beyond crossing / far gate.
6. Return on foot to near gate (now far gate) and close same.
7. Cross on foot and close remaining gate.
8. Advise signaller that crossing procedure is completed and you're on your way.

I make that five crossings in total (four on foot and one in the vehicle). Am I missing something?

 

[Taunton]

I still think it could be implemented quite cheaply, with a single standard piece of equipment, solar powered, at each crossing, connected by 4G to a national database of train locations, mainly fed from the signalling system, with a timer from the nearest signals in both directions, and not going green until the train has confirmed past the crossing, by signal, GPS or another method.

You can get a lot simpler than that, without any equipment at the crossing at all. If I SMS the displayed bus stop number to Transport for London I get an SMS back about 1 second later with how long to the next bus, based on GPS on the buses and some logic at the centre.

 

[QueensCurve]

Don't commercial aircraft land primarily using ILS (= Instrument Landing System) which essentially is a set of radio beams giving pilots vertical and horizontal guidance when on final approach?

ILS was the definitive system for instrument approaches but my understanding, somewhat dated, was that ground-referenced GPS was proposed for GPS approaches.

 

[LOM]

VAMOS and EBI Gate 200 overlay miniature stop lights are already in service and are being fitted to hundreds of UWCs across the country. They use a stand-alone axle counter, red/green light unit and PLC to control it all. Cheap, reliable, fail-safe, proven and simple without introducing novel technology or relying on mobile phone networks or needing trains to be GPS fitted, or a ‘national database of train locations’ which does not exist.

 

[6Gman]

But it isn't at all difficult to misunderstand and do 1 and 4 with the vehicle stopped between the 2 gates. You and I might not do it, but that would be the instinctive thing to do, as it would be the way you would open farm gates, for example.

I've opened a few farm gates in my time and where two gates are close to each other I would open both (unless there are livestock about).

 

[Bald Rick]

But it isn't at all difficult to misunderstand and do 1 and 4 with the vehicle stopped between the 2 gates. You and I might not do it, but that would be the instinctive thing to do, as it would be the way you would open farm gates, for example.

But, surely, anyone with the slightest modicum of common sense wouldn’t park a vehicle across a railway track anymore than they would park a vehicle across a dual carriageway.

I know common sense is an increasingly rare commodity, but even then...

 

[Mcr Warrior]

Please be mindful when posting comments that this thread is being monitored by a relative of the unfortunate individual involved in the incident near Welshpool.

 

[Llanigraham]

You can get a lot simpler than that, without any equipment at the crossing at all. If I SMS the displayed bus stop number to Transport for London I get an SMS back about 1 second later with how long to the next bus, based on GPS on the buses and some logic at the centre.

So that presumes that:
1/ The user has a mobile phone.
2/ That the crossing has a mobile signal. I can assure you that there are LOTS of crossings around here that don't.

 

[ForTheLoveOf]

Don't commercial aircraft land primarily using ILS (= Instrument Landing System) which essentially is a set of radio beams giving pilots vertical and horizontal guidance when on final approach?

ILS was the definitive system for instrument approaches but my understanding, somewhat dated, was that ground-referenced GPS was proposed for GPS approaches.

GPS based approaches (albeit usually with some form of secondary augmentation) are common practice on the approach to runways not fitted with ILS equipment - a surprisingly common occurrence at secondary airfields.

Individual carriers' and aircraft manufacturers' procedures will dictate which is used if both ILS and GPS are available for an approach.

 

[BayPaul]

But, surely, anyone with the slightest modicum of common sense wouldn’t park a vehicle across a railway track anymore than they would park a vehicle across a dual carriageway.

I know common sense is an increasingly rare commodity, but even then...

All too easy to open the first gate, drive forward, and then realise the 2nd gate is shut, surely. I don't think anyone would do it on purpose, but it's not unlikely.

 

[edwin_m]

But, surely, anyone with the slightest modicum of common sense wouldn’t park a vehicle across a railway track anymore than they would park a vehicle across a dual carriageway.

I know common sense is an increasingly rare commodity, but even then...

There may appear to be enough space to park a vehicle between the tracks and the gates, but someone not familiar with the dimensions of trains may not realise they are actually fouling clearances. Or they may be driving a larger vehicle than they are used to. I'm not suggesting these are specifically what happened here, more what could happen with crossings of this type.

 

[BayPaul]

All too easy to open the first gate, drive forward, and then realise the 2nd gate is shut, surely. I don't think anyone would do it on purpose, but it's not unlikely.

It just strikes me that this is an industry that quite rightly takes precautions that many would consider excessive to stop someone stepping out of a door that isn't above a platform, but is happy to rely on a sign to instruct the general public on a procedure that is not simple, and is easy to get wrong.

 

[6Gman]

It just strikes me that this is an industry that quite rightly takes precautions that many would consider excessive to stop someone stepping out of a door that isn't above a platform, but is happy to rely on a sign to instruct the general public on a procedure that is not simple, and is easy to get wrong.

Aren't the vast majority of such crossings not for general public use, but for landowner access?