Braking issue on Caledonian Sleeper causes train to "run away" at Edinburgh

[aleggatta]

Reading through this, it all sounds quite troubling, however I always was surprised that they went with dellners and seperate electrical connections (I know ETS can't be autocoupled!) However having an electrical head on the coupler would enable the possibility of automatically opening air valves upon coupling(This may even be able to be done mechanically, mind you), in the same way a conventional multiple unit operates, removing the risk of someone forgetting to open an isolation cock. yes the twin pipe brake system has worked for years, however just because something is a legacy standard that 'doesnt go wrong unless you do it wrong' as such, shouldn't we still be aiming to prevent wrong side failures and this should not preclude looking at a better way to operate legacy systems? maybe not a complete redesign, just an addition of interlocks to not allow a wrong side failure situation.

 

[modernrail]

At risk of going all Donald Rumsfeld, it was either known known or an unknown unknown. If there is a systemic risk, due to the set up, then it’s a brave or foolhardy person who runs the risk.

If it’s systemic, it will be amazing if it hasn’t cropped up elsewhere before. And what everyone else will do about it.

You comment that the railway doesn’t take chances. It clearly does. Or it didn’t know how lucky it has been. Now it is aware, it has to remove the risk.

I would tend to agree with this. If the RAIB can't do anything at this stage then that is even more troubling.

I don't see that you need to take every piece of rolling stock with this breaking system out of service, but I do see that you have to take every piece of Mark 5A rolling stock out that you uncouple as standard out of service until you have isolated and treated the reason that the risk has in this case turned into reality. I can see the risk on a TP set being a lot smaller from what has been reported so far as they will remain coupled and so perhaps you do not take those out of training/service but then again if they are swapping the 68's around a lot maybe there is cause for concern.

How many times do we see in investigation reports some of the ingredients we have here...disorganised operating company, desperate not to allow any more adverse publicity, general feelings that the railway/other sector does not take adverse risks despite the clear near miss that has clearly come from somewhere.

 

[bastien]

Imagine how much simpler (and less error-prone) this operation would be if these trains were EMUs.

 

[Bald Rick]

I would tend to agree with this. If the RAIB can't do anything at this stage then that is even more troubling.

You need to read up about the role of the RAIB and ORR.

The RAIB is purely an investigatory body, and does not have (and never has had) powers to latter rests with the ORR.

This is exactly the same principle as the AAIB / CAA for air safety. Are you troubled that the AAIB doesn’t enforce safety for the air transport industry?

 

[mcmad]

some of the comments on here, its a wonder some people get out of bed in the morning!

The fact the ORR didn't pull the safety case for the stock shows that the issue is one which has suitable controls and the RAIB report will detail why the fell down on this occasion and what more could potentially be done.

 

[Darandio]

I would tend to agree with this. If the RAIB can't do anything at this stage then that is even more troubling.

As has been outlined multiple times already, even in direct response to some of your posts, the RAIB cannot really do anything at any stage. They can investigate, identify and recommend, but they certainly cannot do the things you are suggesting they can.

It all feels a bit like the Sleeper's 737 Max moment, with a lucky escape in this case.

This is so over the top and not at all comparable.

 

[Bald Rick]

Imagine how much simpler (and less error-prone) this operation would be if these trains were EMUs.

It’s not exactly complex.

The industry has been coupling and uncoupling coaches for around 200 years.

This is by no means the first time a train has failed to brake correctly when commanded to do so, and will not be the last. I well remember a train out of Euston braking for a Watford stop and eventually stopping at Hemel. Shunter’s error that time.

 

[Surreytraveller]

How were the brake applications made, if the train was isolated from the loco?

Because there is air in the brake cylinders. Over time, air leaks out. Air is also used up as a brake application is made and subsequently released to atmosphere when the brakes are released

 

[FQTV]

From the sound of what's been said on this thread and elsewhere if they were to ground trains they'd need to ground every single train which uses the twin pipe brake system. Which I think is basically everything on the entire network. It doesn't appear that this was down to an issue specifically with the new rolling stock. The fact that it is still in service and not grounded should be the big clue to that. The railway doesn't take chances, indeed it's perhaps the most risk averse mode of transport going in this country!

I think that, generally-speaking, (Western) aviation will trump rail for risk aversion and a focus on what they refer to as 'Crew Resource Management' - ie making sure that flight deck superiority can be challenged and that 'blame' is replaced with 'learn from your human mistakes'.

It's quite right to draw the distinction between what the RAIB can do, and what the CAA, EASA, or FAA (for example) can do.

However, to go back to the aviation comparison, time and time again, post-event investigation concludes that many disasters have occurred when more than one circumstance that would, on its own, have been recoverable-from, has co-incided with one or more other similarly recoverable-in-isolation circumstance(s).

It looks as though this is where the 737MAX investigations will likely end up, too.

In the case of aviation, it would also be easy to look at individual circumstances in isolation, and conclude that they're a manageable risk. MCAS on the 737MAX being a case-in-point. However, if MCAS characteristics are such that, reasonably-speaking, the chance of a coincidental circumstance is unreasonably high - whether that's inconsistent training, human reflex response, adverse weather etc., etc., - then it's no use continuing to claim that MCAS is perfectly OK and that there's nothing to worry about.

In the case of the MkVs, then, it may be that (as has also been alluded-to above) the specific complexity of the rolling stock, and/or the software, and/or the training, and/or the human resource, and/or the operating conditions etc., etc., could be the real risk. If that doesn't apply to other rolling stock, or other operations, or other operators, then if a 'grounding' were to occur, I would have thought/hoped that those specifics would be taken into account and the entire network wouldn't grind to a halt.

Subjectively, though, from an industry that does portray a (well-earned) image of being safety-first, it does concern me personally that there are individuals and corporate entities who may be prone to looking too narrowly at individual circumstances, and not appreciating-fully the implications of two things going wrong at the same time, nor that the risk of that may be heightened by complexity and/or lack of resource.

 

[BRX]

Because there is air in the brake cylinders. Over time, air leaks out. Air is also used up as a brake application is made and subsequently released to atmosphere when the brakes are released

Yes, but to make the applications, the driver would have to have control over the system. I don't see how the driver can have control over the system if it's isolated from the loco.

 

[bastien]

It’s not exactly complex.

The industry has been coupling and uncoupling coaches for around 200 years.

This is by no means the first time a train has failed to brake correctly when commanded to do so, and will not be the last. I well remember a train out of Euston braking for a Watford stop and eventually stopping at Hemel. Shunter’s error that time.

So as you say, shunting is something that should be avoided if at all possible.

 

[O L Leigh]

Is there really any need to be giving the pot another stir?

You comment that the railway doesn’t take chances. It clearly does.

No it doesn't. What happens is that it suffers from mistakes, and I firmly believe that this is what the RAIB will report back to say.

I am hugely intrigued if the RAIB has decided to overlook all this and let the train continue to run.

Who are we to gainsay the RAIB? None of us know for certain what has happened to cause this incident (although a good number have a very good idea) so none of us can criticise them.

 

[a_c_skinner]

It's a serious incident no doubt but we don't at this point know whether it had anything at all to do with the new stock.

Yes, but we do need to know (and I assume we do) that it won't happen again. I'd have more faith in CS management if they had said this was a very serious incident, we believe we know what caused it but in any case we have put into place measures that will stop it happening again. As it is we just got flannel. I know, I used to compose flannel in a very tiny part of my old job.

 

[Leo1961]

some of the comments on here, its a wonder some people get out of bed in the morning!

The fact the ORR didn't pull the safety case for the stock shows that the issue is one which has suitable controls and the RAIB report will detail why the fell down on this occasion and what more could potentially be done.

We really do need to find a "LIKE" button for this forum...

 

[InOban]

On the BBC website, it's stated that the train was eventually halted by the application of the emergency brake by the train manager. I'm sure others can explain the nature of the emergency brake in modern stock.

 

[hexagon789]

On the BBC website, it's stated that the train was eventually halted by the application of the emergency brake by the train manager. I'm sure others can explain the nature of the emergency brake in modern stock.

Air vents from brake pipe, brakes come on.

Presumably there was sufficient air left in the coaches to allow an emergency application to be made by the TM, but the lack of connection between coaches and loco meant the driver couldn't control the brakes on the coaches.

 

[alxndr]

Yes they are last resort, so anything else should be even more safe ! , so no need for any new systems ,just use the current systems properly and if not safe dont work.Been the case for years.

As has already been pointed out to you, if the brakes on the train are ineffective no amount of red signals, marker boards, or dets will stop a train coming through. It is a risk we take, albeit a small one, that trains will stop at such signals.

If the “orange army” were working under the protection of a lookout (which is certainly allowed outside Scotland, if not inside it), then it’d be no different to any other train approaching.

If they were working under the protection of a line blockage, and therefore not expecting any trains to approach, things would be different and they would be at risk should a train approach unexpectedly.

It would indeed seem fortunate that no-one was working under a line blockage east of the station.

You've explained it far better than I have! The only thing I'd add is that if failed brakes cause the train to overspeed anyone using lookout protection is still at risk as their warning time will be reduced.

 

[BRX]

Is it a standard procedure that if a train runs through a booked stop, on-board staff should pull the emergency brake, or only after consultation with the driver?

Reading the earlier comments about how stopping other trains might not be desirable in the case of a runaway; if a train runs through a booked stop, it might be for good reasons that the on-board staff don't know about.

 

[matacaster]

It would appear that the same rigorous 100% approach taken to fail safety of the manual / hardware / software interface in signalling systems has not been replicated and adequately considered or applied in this case.

Whilst I feel that there is sometimes a bit of overkill on railway safety (as compared to say road where deaths / injuries which are entirely avoidable often lead to little or no subsequent action to prevent reoccurrence - indeed our local council highways will not introduce new safety measures UNLESS sufficient accidents have occurred!!!) I'm afraid that failsafe electronic interloccking of brakes to prevent train moving if the braking system is incorrectly configured or inoperable is manifestly necessary. If its found to be human error in the first instance, say in connecting pipes or cables (all humans make mistakes) or in maintenance then one must look at the manufacturer, its employees , its safety case and regulators who approved the DESIGN, TESTING and IMPLEMENTATION of the failsafe system, as its clearly NOT failsafe. Caledonian sleeper operatonal personnnel (or whoever they subcontract to) training should be examined, but that is a side issue, with braking, no one individual person on the coalface should have to be solely responsible.

 

[jthjth]

As someone who doesn’t really understand modern train braking systems at all, could someone knowledgeable please explain the following?:

I’m assuming the problem started when the train was split. When this happens why isn’t the air released from the system putting the coach brakes on? Then this would require the locomotive to recharge the system and the train would be unable to move until a properly working braking system was established. I’m not sure I understand the exact meaning behind the brakes being “isolated” and why this is necessary.

 

[O L Leigh]

I'm afraid that failsafe electronic interloccking of brakes to prevent train moving if the braking system is incorrectly configured or inoperable is manifestly necessary. If its found to be human error in the first instance, say in connecting pipes or cables (all humans make mistakes) or in maintenance then one must look at the manufacturer, its employees , its safety case and regulators who approved the DESIGN, TESTING and IMPLEMENTATION of the failsafe system, as its clearly NOT failsafe. Caledonian sleeper operatonal personnnel (or whoever they subcontract to) training should be examined, but that is a side issue, with braking, no one individual person on the coalface should have to be solely responsible.

...and the RAIB will be looking into all of this.

However, the call to install what is, in effect, and electrical brake continuity wire to every single piece of loco-hauled rolling stock (freight and passenger) together with every single loco is overkill. This is most likely to have been a procedural failing as any technical issue with the brakes becoming isolated on Mk5 stock would have been discovered by now. As such, this is a learning point for the staff and operators on these trains.

My own personal feelings on this matter is that this stock's use of Delner autocouplers with built-in air connections may have been confusing to the shunter, as the instructions for coupling and brake-testing these trains will be new and different to all other loco-hauled stock. These couplers will use star valves or similar that are effectively automatic in operation (they are held closed by the air pressure in the pipe and are opened when pressed together during coupling) and, as such, I'm wondering if the air cock on the loco bufferbeam controlling the supply to the coupler head had been left open. This may have confused the shunter who will have been used to coupling trains and opening the air cocks prior to departure and tricked him/her into accidentally isolating the supply.

But then, the RAIB will tell us once they've finished their investigation.

 

[37057]

As someone who doesn’t really understand modern train braking systems at all, could someone knowledgeable please explain the following?:

I’m assuming the problem started when the train was split. When this happens why isn’t the air released from the system putting the coach brakes on? Then this would require the locomotive to recharge the system and the train would be unable to move until a properly working braking system was established. I’m not sure I understand the exact meaning behind the brakes being “isolated” and why this is necessary.

I think that's what a lot of people are failing to understand.

I'm guessing there aren't many on this forum who are familiar with the brake system on the Mk5s and the procedure for coupling and uncoupling (professionally trained), therefore there is a lot open to interpretation based on peoples experiences with more traditional methods of attaching trains and configuring brake systems.

May as well wait until there's a report but then that may not even be made public.

 

[Bertie the bus]

My own personal feelings on this matter is that this stock's use of Delner autocouplers with built-in air connections may have been confusing to the shunter, as the instructions for coupling and brake-testing these trains will be new and different to all other loco-hauled stock. These couplers will use star valves or similar that are effectively automatic in operation (they are held closed by the air pressure in the pipe and are opened when pressed together during coupling) and, as such, I'm wondering if the air cock on the loco bufferbeam controlling the supply to the coupler head had been left open. This may have confused the shunter who will have been used to coupling trains and opening the air cocks prior to departure and tricked him/her into accidentally isolating the supply.

If somebody is confused by their job it suggests either poor recruitment or poor training. If somebody in a safety critical role is confused that makes it more serious. Hasn’t the Lowlander been solid Mk5s for a while? It isn’t as though the sleeper through Carstairs is sometimes Mk 3s and sometimes Mk 5s.

 

[O L Leigh]

If somebody is confused by their job it suggests either poor recruitment or poor training. If somebody in a safety critical role is confused that makes it more serious.

I'm not going to speculate any further on this. As I said, it is just my personal feelings. No-one yet knows precisely what has happened to cause this incident, so I could be spectacularly wide of the mark and the causes could come down to something entirely different. What I wanted to try and do was to deflect some of the wilder speculation regarding technical issues, as all the signs are currently pointing away from this being the cause.

However, to take the broad thrust of your post, human factors could be at work here, and these are far more complex than simple recruitment and training. There's a whole galaxy of reasons why an experienced, well-trained person can make a mistake in their everyday duties.

 

[edwin_m]

How were the brake applications made, if the train was isolated from the loco?

The train brake pipe was still connected and continuous, but something had been isolated that prevented the air from the brake pipe replenishing the reservoir on the loco. After the loco lost braking it wouldn't have been that noticeable to the driver as the wagons were still braked. [Referring to the incident from my previous post, not the one that is the subject of this thread].

Imagine how much simpler (and less error-prone) this operation would be if these trains were EMUs.

They would still have needed diesel haulage for the Highland sleeper north of Edinburgh. I suspect there is more potential for errors when hauling an EMU dead than when coupling a loco to hauled stock.

It would appear that the same rigorous 100% approach taken to fail safety of the manual / hardware / software interface in signalling systems has not been replicated and adequately considered or applied in this case.

Signalling relies on the driver obeying the signals and not isolating the TPWS, and on driver and signaller following procedures to keep trains moving when the signalling has failed. Every on-board safety system that can stop the train has an isolation facility, as being failsafe it also stops the train in the event of a fault and again there needs to be a way of keeping things moving.

All these are examples where the railway relies for safety on people following correct procedure. Achieving failsafe braking is the same. I guess loss of braking serious enough to warrant at RAIB report happens about every five years, and off the top of my head I can't think of any casualty accidents in the last few decades in the UK (though it was the cause of a serious accident in France). So while it is right to investigate and learn lessons from this, I don't think it's a case of knee-jerk reactions. Adding an extra monitoring system to the brakes may just create yet another thing that can fail safe and need isolating according to a procedure.

 

[Tomnick]

As someone who doesn’t really understand modern train braking systems at all, could someone knowledgeable please explain the following?:

I’m assuming the problem started when the train was split. When this happens why isn’t the air released from the system putting the coach brakes on? Then this would require the locomotive to recharge the system and the train would be unable to move until a properly working braking system was established. I’m not sure I understand the exact meaning behind the brakes being “isolated” and why this is necessary.

I don't know exactly how the braking system works on these trains or what went wrong, but most braking systems on the railway are necessarily more complex than "no air supply = brakes held on" because there are situations where you need to move the train without a properly working braking system on one or more vehicles (hence "isolated") or - much less so nowadays - shunt vehicles unbraked. The principle behind a twin-pipe system is that the brakes are held on by air pressure (supplied by the train pipe which should be maintained at pressure and with substantial reservoirs on each vehicle to ensure a decent supply), with air admitted to an adjacent chamber in each brake cylinder (supplied by the brake pipe where the pressure is varied to control the strength of a brake application) to reduce the pressure differential and partially or completely release the brakes. If the train pipe fails for whatever reason, the pressure in the brake reservoirs should instead be restored via the brake pipe when the brakes are released. It's all reasonably fail-safe and with some sensible precautions (e.g. to prevent the train and brake pipes being cross-connected), but not entirely foolproof, hence the importance of following proper procedure and the various brake tests...

 

[ComUtoR]

But going back to the braking system issue, when was the last time something like this happened?

Not quite the same but Southeastern had a runaway in 2016 (I think)

Also similar (were a train couldn't stop) Again on Southeastern. The Stonegate incident.

 

[O L Leigh]

Not quite the same but Southeastern had a runaway in 2016 (I think)

Also similar (were a train couldn't stop) Again on Southeastern. The Stonegate incident.

I can't find your first incident in the archive, but the Stonegate overrun was quite different in that the train's brakes were working fine but the sanders were empty.

 

[158756]

If this train had been originally routed into a dead end platform would this have been a full on crash?
.

If the signaller wasn't alerted until too late, if the through platforms were occupied, if there was some very low speed pointwork involved... Yes.

Also if the train had been required to wait at a junction, at Haymarket, for a platform at Edinburgh, if for any reason there wasn't a clear route to Abbeyhill....

But the loco stays attached to the Glasgow portion rather than being added in the Edinburgh case

It would have stopped a mile or so after the booked call at Motherwell.

True, in normal operations a train in this condition probably wouldn't reach Glasgow Central. But that isn't by design. Accidents often involve a number of problems occurring at once, or some unusual situation that allows an issue to escalate where it wouldn't otherwise.

If one day the loco was for some reason swapped on the Glasgow portion, and there was a diversion away from Motherwell, a train running without working brakes could end up on the concourse in Glasgow. Unlikely, but so should be any train running without functioning brakes, and we've seen that can happen.

 

[yorkie]

I would tend to agree with this. If the RAIB can't do anything at this stage then that is even more troubling.

I don't see that you need to take every piece of rolling stock with this breaking system out of service, but I do see that ....

Did you not see @ainsworth74's reply to your previous post, clarifying your misunderstanding about the role of RAIB?

I'll take the rest of the post with a pinch of salt!