Doing away with signalling?

[BigDog]

Would it have any implications for engineering or maintenance works, effecting line blockages & possessions?

 

[jfowkes]

Would it have any implications for engineering or maintenance works, effecting line blockages & possessions?

There would be less track-side cabling and equipment to maintain, though as mentioned by others, it certainly doesn't remove all of it.

So in theory that translates to shorter/fewer blockages and possessions, or more work able to be carried out in the same blockage/possession.

 

[plugwash]

I'd assume there would also need to be some changes the procedures for a train entering an engineering possession to account for ETCS.

 

[Bald Rick]

I'd assume there would also need to be some changes the procedures for a train entering an engineering possession to account for ETCS.

As per the rule book for ETCS.

 

[Deepgreen]

Do you want to split hairs over the choice of words? Would you rather significant? It's certainly pretty common on secondary intercity and rural lines

It's not "splitting hairs", it's an important difference. There are pockets of semaphores left, but I would estimate that 90+% of today's railway is not semaphore signalled.

 

[Lurcheroo]

5. It should reduce the need to route knowlege on the part of drivers (though how this will play out politically I have no idea)

Point 5 - I don't predict any point in the future where drivers' route knowledge would be allowed to be any less extensive and detailed than it is currently.

I don't see that happening. Drivers will not be expected to use ETCS as some kind of SatNav and will still need to know the associated speeds and route indications for the journey they are making, otherwise how will they know if they've been wrong routed?

Apologies, it’s a bit of a long one but hope it gives a reasonable in sight as to ERTMS and clears up some common misconceptions about driving with it.

When you have full supervision all the speeds are displayed to you via the DMI so it is certainly helpful but you still need a good idea of where they are so that you can drive effectively.
What is really really key though, is that sometimes you are driving not fully supervised.

There are 2 other modes ‘on sight’ (OS) and ‘staff responsible’ (SR).

OS gives you permission to pass one block marker and is the kids you should get when starting a journey, such as having terminated at a terminus station, swapping ends and beginning and journey going the other way. It is also the mode given for permissive working such as entering an occupied platform.
OS has a maximum speed of 40KPH.

SR is an unsupervised mode in which you would not normally be using on a running line. There are a number of reasons you might end up in SR such as soaking to transition to level 2 or losing connection with the Radio Block Centre.
Crucially it does not give you permission to pass any block markers or begin a movement, that is done via a written order from the signaller.

Once you are in SR, by default the max speed is 40KPH but if given permission you may raise the parameters which will allow a maximum of 80KPH. You must be prepared to stop in the distance you can see to be clear so you would not just travel at 80KPH the entire time.
There are no line side speed boards for normal running but for degraded running such as in OS and SR which will not limit your speed there are degraded speed boards. Where line speed is over 80KPH generally it will be 80KPH and where it is lower, eg 65KPH normally then the degraded speed Board will show 65KPH but there are some places where the degraded speed does not match the normal speed in that sense.

You must also be prepared to stop at the next block marker, I’m not sure what it will be like on mainlines but we can have many miles between block markers so you could be travelling 10+ miles before you get to the next one.

As you approach the block marker you should be offered on sight (which you must accept) but need to be prepared to stop in case it does not happen.

SR will not prevent you from passing a block marker that you don’t have permission to so would be a SPAD. Block markers have by them a balise which if passed in SR will apply the emergency brake (same as TPWS really).


So in essence, you need to know 2 speed profiles (kind of) and the locations of block markers is essential, along with all the normal route features a driver would be expected to know plus a few extra bits such as where you want your MA to extend by otherwise you need to start braking for the end of authority.

As for routing, in some places you can tell by the speed profile that is given where you’re being routed but the driver is essentially washed of any responsibility of wrong routing as we’re not expected to check it.

Unfortunately due to the way it’s setup we can not stop just before the junction have and have the route set correctly for us as ERTMS locks the route out and the signaller can not change it. If you spotted it and stopped at the block marker before hand then you could call the signaller and the route can be taken off you and then re given correctly but I’ve not heard of that happening as you would have to notice it and get stopped very early!

 

[Omnishambles]

From memory of a plan maybe 7 or 8 years ago there was a view that the last remaining renewals would be done in 2064, one of the last being Tyseley No.1.
The a) ramping up to 4,000SEU pa and b) the funding to carry out cab fitment has always been where my scepticism kicks in.

 

[The Planner]

From memory of a plan maybe 7 or 8 years ago there was a view that the last remaining renewals would be done in 2064, one of the last being Tyseley No.1.
The a) ramping up to 4,000SEU pa and b) the funding to carry out cab fitment has always been where my scepticism kicks in.

That plan is worthless now.

 

[MarkyT]

You must also be prepared to stop at the next block marker, I’m not sure what it will be like on mainlines but we can have many miles between block markers so you could be travelling 10+ miles before you get to the next one.

ERTMS really should have distant boards available for these circumstances, also equipped with a balise that alerts and requires action like a modern AWS. Perhaps a yellow arrow on a black board or maybe a yellow and black version of the purple shunt marker. I support advance warning boards and balises for temporary speed restrictions too that would automatically modify MA speed in any mode. It'd all be passive lineside kit so no significant maintenance, and it's inspected and tested by every passing train.

 

[Omnishambles]

That plan is worthless now.

Worthless not long after it was written to be fair. Remember seeing a version back in 2015/16 which at the time was version 22 of the plan. Said it all really

 

[Lurcheroo]

ERTMS really should have distant boards available for these circumstances, also equipped with a balise that alerts and requires action like a modern AWS. Perhaps a yellow arrow on a black board or maybe a yellow and black version of the purple shunt marker. I support advance warning boards and balises for temporary speed restrictions too that would automatically modify MA speed in any mode. It'd all be passive lineside kit so no significant maintenance, and it's inspected and tested by every passing train.

That is potentially a rather good idea.

No need for TSR’s as they can be added and removed from the ERTMS system with ease so your Speed profile is already modified.

 

[InkyScrolls]

Apologies, it’s a bit of a long one but hope it gives a reasonable in sight as to ERTMS and clears up some common misconceptions about driving with it.

When you have full supervision all the speeds are displayed to you via the DMI so it is certainly helpful but you still need a good idea of where they are so that you can drive effectively.
What is really really key though, is that sometimes you are driving not fully supervised.

There are 2 other modes ‘on sight’ (OS) and ‘staff responsible’ (SR).

OS gives you permission to pass one block marker and is the kids you should get when starting a journey, such as having terminated at a terminus station, swapping ends and beginning and journey going the other way. It is also the mode given for permissive working such as entering an occupied platform.
OS has a maximum speed of 40KPH.

SR is an unsupervised mode in which you would not normally be using on a running line. There are a number of reasons you might end up in SR such as soaking to transition to level 2 or losing connection with the Radio Block Centre.
Crucially it does not give you permission to pass any block markers or begin a movement, that is done via a written order from the signaller.

Once you are in SR, by default the max speed is 40KPH but if given permission you may raise the parameters which will allow a maximum of 80KPH. You must be prepared to stop in the distance you can see to be clear so you would not just travel at 80KPH the entire time.
There are no line side speed boards for normal running but for degraded running such as in OS and SR which will not limit your speed there are degraded speed boards. Where line speed is over 80KPH generally it will be 80KPH and where it is lower, eg 65KPH normally then the degraded speed Board will show 65KPH but there are some places where the degraded speed does not match the normal speed in that sense.

You must also be prepared to stop at the next block marker, I’m not sure what it will be like on mainlines but we can have many miles between block markers so you could be travelling 10+ miles before you get to the next one.

As you approach the block marker you should be offered on sight (which you must accept) but need to be prepared to stop in case it does not happen.

SR will not prevent you from passing a block marker that you don’t have permission to so would be a SPAD. Block markers have by them a balise which if passed in SR will apply the emergency brake (same as TPWS really).


So in essence, you need to know 2 speed profiles (kind of) and the locations of block markers is essential, along with all the normal route features a driver would be expected to know plus a few extra bits such as where you want your MA to extend by otherwise you need to start braking for the end of authority.

As for routing, in some places you can tell by the speed profile that is given where you’re being routed but the driver is essentially washed of any responsibility of wrong routing as we’re not expected to check it.

Unfortunately due to the way it’s setup we can not stop just before the junction have and have the route set correctly for us as ERTMS locks the route out and the signaller can not change it. If you spotted it and stopped at the block marker before hand then you could call the signaller and the route can be taken off you and then re given correctly but I’ve not heard of that happening as you would have to notice it and get stopped very early!

This was a very interesting read, thank you.

 

[zwk500]

ERTMS really should have distant boards available for these circumstances, also equipped with a balise that alerts and requires action like a modern AWS. Perhaps a yellow arrow on a black board or maybe a yellow and black version of the purple shunt marker. I support advance warning boards and balises for temporary speed restrictions too that would automatically modify MA speed in any mode. It'd all be passive lineside kit so no significant maintenance, and it's inspected and tested by every passing train.

Isn't the whole point of ETCS L2 that the distance of the remaining Movement Authority is displayed to the Driver in the cab, so there's no need for distant boards?

 

[MarkyT]

Isn't the whole point of ETCS L2 that the distance of the remaining Movement Authority is displayed to the Driver in the cab, so there's no need for distant boards?

Yes in normal operations, but this would be for degraded modes when there's no other information available and drivers have difficulty knowing where they are relative to the next block marker where they must be prepared to stop. It's a particular problem in very long single line blocks typical on the Cambrian.

 

[zwk500]

Yes in normal operations, but this would be for degraded modes when there's no other information available and drivers have difficulty knowing where they are relative to the next block marker where they must be prepared to stop. It's a particular problem in very long single line blocks typical on the Cambrian.

Ah fair enough, yes I guess the Mile/KM Posts wouldn't be sufficient for that purpose.