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Serious Accident in Bavaria

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BRX

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Not sure that I agree that a signaller talking past Vs a PoSA are the same.
In talking past, there is a two way conversation. The signaller might say, 'Fault on the signal, can't get it to clear, but I'm authorising you to pass it' and the driver might say 'What about the train I normally pass here? Where will I pass it? Cue lightbulb moment.
With a PoSA, the driver just sees it and proceeds, assuming that the signaller has their reasons for lighting it.

Also, presumably with a conversation a certain amount of time passes by between the signaller deciding they're going to give permission, and actually giving permission.
 
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ComUtoR

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Not sure that I agree that a signaller talking past Vs a PoSA are the same.

It's visual authority instead of verbal.

In talking past, there is a two way conversation. The signaller might say, 'Fault on the signal, can't get it to clear, but I'm authorising you to pass it' and the driver might say 'What about the train I normally pass here? Where will I pass it? Cue lightbulb moment.

This is what happens.

The Signaller : "Driver of [headcode], Due to [insert reason] I am unable to give you a clear aspect. I am authorising you to pass [signal number] at danger then obey all other aspects".

The Driver : "Ok Signaller, due to [insert reason] you are unable to give me a clear aspect and are authorising me to pass [signal number] at danger then obey all other aspects, is that correct ?"

The Signaller : "That is correct Driver. Signaller out."

The Driver : "Driver out."

The Signaller is giving me an instruction. We are not having a conversation. I repeat back to show I have a clear understanding and then make the movement.

The extent of my involvement is to obey the Signallers instructions to the letter. Not start questioning them. Before authority to proceed is given many other checks have already taken place. All the relevant safety checks have been carried out, the line has been examined and conflicting moves been secured using block instruments and the interlocking is doing its job. It is like where they have stopped stating for us to proceed at caution... and telling us to remember to isolate the TPWS. Our actions are explicitly set out in the rule book and the expectation is for us to carry out our duties correctly. They don't need to remind us but it is still a safe method of working. All I need to know is can I pass and how far for. (PoSA is until the next signal)


With a PoSA, the driver just sees it and proceeds, assuming that the signaller has their reasons for lighting it.

Yep. The PoSA is replacing the conversation. That all. Once everything has been checked and its considered safe to run trains through the affected section the Signaller would typically stop every train and caution them through verbally, every, single, time. Now you can just PoSA each train through instead but all the checks have been carried out already. There is a lot of trust and I do see it being hard to give that complete trust to someone miles away.

We may call them many names and swear at the GSMR but we do trust the Signaller and signalling system and I have no doubt that they also trust us to understand that its safe to proceed. When its not safe, they tell us.

The PoSA is probably the simplest concept to grasp in the rule book.
 

Bletchleyite

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So a driver is not allowed to question a signaller even if they have a niggling doubt?

Madness. Someone needs to throw the book of Cockpit Resource Management at the railway.
 

D1009

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It's visual authority instead of verbal.



This is what happens.

The Signaller : "Driver of [headcode], Due to [insert reason] I am unable to give you a clear aspect. I am authorising you to pass [signal number] at danger then obey all other aspects".
Does the signaller not tell the driver at what speed to proceed to the next signal, or is the driver supposed to know that from the rules?
 

ComUtoR

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Nothing is stopping the Driver from questioning. The standard rule is if you believe its unsafe, don't do it.

You were NEVER allowed to pass the signal without a reason given and it had to be a reason that was on the accepted list. People used to go past signals at red without being given a reason and it would sometimes have serious consequences. That is with Driver/Signaller in full communication.

When we are authorised to pass then yeah, we have total faith and trust in the Signaller. That is a core part of the role.

As I mentioned, I have heard radio tapes from incidents and many start of with the Driver and Signaller falling into conversation and each one questioning each other. Again, its safe to get the PoSA because everything is explicitly implied. There will be no question of authority not given and no question of what signal it applies to. It has become very very black and white.

It would truly worry you if you heard the conversations I have. The most unsafe part of passing a signal at danger IS the conversation between Driver and Signaller. - Scary.

If you got a PoSA and still felt unsure then absolutely question it. The first time through feels odd and like there is something wrong. With everyone doing their job then its still very very very safe and possibly safer than a conversation.
--- old post above --- --- new post below ---
Does the signaller not tell the driver at what speed to proceed to the next signal, or is the driver supposed to know that from the rules?

It is implied. You MUST proceed at caution. Yes it is a rulebook instruction. They used to but now its accepted that we will ALWAYS proceed at caution. Even with the German Zs1 signal they are restricted to 40kph so IF that was what was given to the Drivers in this incident then they should not have been going linespeed
 
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edwin_m

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Thanks for the explanation. I don't recall ever seeing one, but having had a quick google I read that they were only introduced in December so that would explain why.

I shall have to look out for one next time I'm out and about on the rails.

It's a bit hard to tell because they just look like normal subsidiary aspects until they are lit up. The only place I've seen them is the Thameslink core.
 

Bletchleyite

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Even with the German Zs1 signal they are restricted to 40kph so IF that was what was given to the Drivers in this incident then they should not have been going linespeed

I think the problem here might have been (and we will no doubt find out in due course) that the Zs1 was given only to one of the drivers; the other one got a green and was proceeding at linespeed.

If both were driving on sight I would not have expected any collision, or at worst a minor prang.
 

the-gog

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It's a bit hard to tell because they just look like normal subsidiary aspects until they are lit up. The only place I've seen them is the Thameslink core.


According to Railsigns.uk: "The first line to be equipped with PoSAs was the East London Line, in 2010."
 

BRX

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It would truly worry you if you heard the conversations I have. The most unsafe part of passing a signal at danger IS the conversation between Driver and Signaller. - Scary.

Why is this?
 

ComUtoR

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Why is this?

Because the weakest link is people.

The system will fail safe and the interlocking will prevent a conflicting move. The human aspect is where the system fails. When people question and fall into casual conversation it leads to mistakes and lack of concentration. Which is why we keep conversation to be "Safety Critical Communication" only.

As an example I know of an incident where someone was authorised past a signal into a station. The conversation went along the lines of "you are authorised to pass signal x at danger then you are clear into station" Unfortunately there was another signal before the station, also at red.

We have had trains authorised past signals but the wrong train was given authority and as no-one had confirmed the headcodes.

Lack of understanding to how far the movement is to take place. We had a SPAD onto a mainline as the Driver believed he was being authorised to carry out the shunt move but he wasn't. There was an expectation for him to stop at the position light.

There was almost a head on collision because there wasn't a clear understanding as to which signal was allowed to be passed because the Driver was in one place and the Signaller thought they were somewhere else and there was confusion over which signal.

I have heard stand up blazing rows on the radio tapes where Driver/Signaller have had a disagreement or the Driver has questioned the Signallers actions.

We have even had trains authorised past a signal by the incorrect signaller because the CSR connected to the wrong box.

People do not fail safe.

It is not my place to question if the 0834 is in front or behind me, or usually passed the junction first. My job is the safety and running of my train and I have full confidence that when given authority by the one person who is responsible for the signal then I happy to accept that.

With a PoSA it is an absolute.

With this incident if we accept the premise that the system was working correctly then human error has caused the crash. If we accept that all the humans involved carried out their duties to the letter then the system caused the crash. It is reasonable to accept the first premise.

Many incidents are due to communication errors.
--- old post above --- --- new post below ---
I think the problem here might have been (and we will no doubt find out in due course) that the Zs1 was given only to one of the drivers; the other one got a green and was proceeding at linespeed.

If both were driving on sight I would not have expected any collision, or at worst a minor prang.

Potentially I agree. I don't know what is interlocked and what isn't or from viewing the video if there even is a Zs1 signal. Even if it is what we both believe then the line wasn't checked and authority to pass was given whilst a train was in the section. That is not a failure of the system. It will be human error.

Or one had a SPAD but then INDUSI should have intervened.

My other suspicion is that the signals for the level crossing are only interlocked for the crossing (again doubtful) but one of the units must have passed the level crossing signal for some reason. Again it sounds like human error there.

My understanding is that being given the Zs1 means 40kmp as far as instructed/expected (next signal ?) and that would have been the crossing. The other train would/should of had a red. More human error by the sounds.

Again we would need confirmation from those who know that before being given the Zs1 the line must be checked.
 
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BRX

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Because the weakest link is people.

The system will fail safe and the interlocking will prevent a conflicting move. The human aspect is where the system fails. When people question and fall into casual conversation it leads to mistakes and lack of concentration. Which is why we keep conversation to be "Safety Critical Communication" only.

As an example I know of an incident where someone was authorised past a signal into a station. The conversation went along the lines of "you are authorised to pass signal x at danger then you are clear into station" Unfortunately there was another signal before the station, also at red.

We have had trains authorised past signals but the wrong train was given authority and as no-one had confirmed the headcodes.

Lack of understanding to how far the movement is to take place. We had a SPAD onto a mainline as the Driver believed he was being authorised to carry out the shunt move but he wasn't. There was an expectation for him to stop at the position light.

There was almost a head on collision because there wasn't a clear understanding as to which signal was allowed to be passed because the Driver was in one place and the Signaller thought they were somewhere else and there was confusion over which signal.

I have heard stand up blazing rows on the radio tapes where Driver/Signaller have had a disagreement or the Driver has questioned the Signallers actions.

We have even had trains authorised past a signal by the incorrect signaller because the CSR connected to the wrong box.

People do not fail safe.

It is not my place to question if the 0834 is in front of behind me, or usually passed the junction first. My job is the safety and running of my train and I have full confidence that when given authority by the one person who is responsible for the signal then I happy to accept that.

With a PoSA it is an absolute.

With this incident if we accept the premise that the system was working correctly then human error has caused the crash. If we accept that all the humans involved carried out their duties to the letter then the system caused the crash. It is reasonable to accept the first premise.

Many incidents are due to communication errors.

Given that some of these incidents seem to be a result of errors by the signaller, I'm not sure why you put absolute and total trust in the signallers!

I can see that using the lights removes any ambiguity about which signal the signaller is giving the authority to pass.

But presumably it doesn't remove any ambiguity about which train is sitting at it, whereas a conversation potentially could remove this.

And if the signaller and the driver are having a row, then the problem is with one or both of those individuals rather than the system.

Seems like both methods have their pros and cons - surely the safest would be a conversation, followed by the actual authority being given via the lights.
 

ComUtoR

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Given that some of these incidents seem to be a result of errors by the signaller, I'm not sure why you put absolute and total trust in the signallers!

People make mistakes. That will never change. We can't be running about questioning everyone and with the belief that everyone isn't doing their job correctly. Possibly one of the hardest things to get your head round as a Driver is to put that trust in others and in the system. Also, part of our job is to make sure we are doing it correctly too. It is easy to be talked into doing something wrong and a single word can change the entire meaning of a sentence.

I can see that using the lights removes any ambiguity about which signal the signaller is giving the authority to pass.

I'm happy you can see that. It is integral

But presumably it doesn't remove any ambiguity about which train is sitting at it, whereas a conversation potentially could remove this.

The importance of the Train describer and setting up correctly. It still allows it to be passed safely just the wrong train. I hope that the Signaller side has that protection where the correct train must be signalled past.

And if the signaller and the driver are having a row, then the problem is with one or both of those individuals rather than the system.

Exactly. People are where it fails.

Seems like both methods have their pros and cons - surely the safest would be a conversation, followed by the actual authority being given via the lights.

Interesting and worthy of discussion, just not in this thread.
 

nom de guerre

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It's visual authority instead of verbal.



This is what happens.

The Signaller : "Driver of [headcode], Due to [insert reason] I am unable to give you a clear aspect. I am authorising you to pass [signal number] at danger then obey all other aspects".

The Driver : "Ok Signaller, due to [insert reason] you are unable to give me a clear aspect and are authorising me to pass [signal number] at danger then obey all other aspects, is that correct ?"

The Signaller : "That is correct Driver. Signaller out."

The Driver : "Driver out."

The Signaller is giving me an instruction. We are not having a conversation. I repeat back to show I have a clear understanding and then make the movement.

The extent of my involvement is to obey the Signallers instructions to the letter. Not start questioning them. Before authority to proceed is given many other checks have already taken place. All the relevant safety checks have been carried out, the line has been examined and conflicting moves been secured using block instruments and the interlocking is doing its job. It is like where they have stopped stating for us to proceed at caution... and telling us to remember to isolate the TPWS. Our actions are explicitly set out in the rule book and the expectation is for us to carry out our duties correctly. They don't need to remind us but it is still a safe method of working. All I need to know is can I pass and how far for.

S5/3.1 clearly states that we must instruct drivers to proceed at caution when talking them past (barring a handful of exceptions, eg SLW, TBW).

The parts that have been removed recently are the additional instruction to "be prepared to stop short of any obstructions" - which I find some drivers still 'repeat' back to me, even though I haven't said it in the first place! - and the TPWS reminder. I still issue the latter, whenever applicable, as drivers do occasionally forget to press the override (which can then cause delays at inconvenient places). The way I do it is simply to state: 'Just to remind you driver, signal X is fitted with TPWS' - there is (was) no requirement to tell you how to act upon that information, as it is assumed you will know. I certainly would never tell a driver to "isolate the TPWS" (in an S5 situation): not required, none of my business and it could potentially cause dangerous and completely unnecessary misunderstandings.
--- old post above --- --- new post below ---
I have heard stand up blazing rows on the radio tapes where Driver/Signaller have had a disagreement or the Driver has questioned the Signallers actions.

The most-played one of these is actually quite instructive: it shows how poor the signaller's S5 script was a few years ago, as well as the ridiculously pedantic approach to comms at the time.

Thankfully it's a bit less anal these days.
 
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ComUtoR

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none of my business and it could potentially cause dangerous and completely unnecessary misunderstandings.

Yep. Works both ways too. What is happening to other trains is none of my buisness :)

The most-played one of these is actually quite instructive: it shows how poor the signaller's S5 script was a few years ago, as well as the ridiculously pedantic approach to comms at the time.

I think I know the one. Are you thinking of the one where they refused to agree about giving authority ? The Driver refused to move because the Sig didn't specifically state "I am authorising you.." then there was a mexican standoff ?

Your totally right. The tapes are very instructive. Silly things like "isolate the tpws" caused miscommunication like you rightly said. It has two meanings. WE have also had issues where Drivers have been told to "set back"

Even "caution" can be misunderstood :/ I must admit that the German instruction to have a specific limited speed seems like a sensible option.
 
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This is how I thought it was, and is much more reassuring than that a signaller could, without being forced to involve someone else, press a button to clear a signal onto a single line where another train could be proceeding at linespeed with no knowledge of the issue.

Regardless of how the authority is conveyed to the driver whether it be by phone/radio conversation or PoSA, to my mind it just cannot be right that if there is a failure of a single line system that the signalman can authorise a train into the section without recourse to anyone else or appointing pilotmen etc.
This sounds like an accident waiting to happen, which unfortunately it did.

Another point as has been said by others. The Down train was only 4 minutes late, so whatever was done, was done in haste to save a few minutes. Otherwise the signalman would have just held the Up one at Kolbermoor and done the cross as per the WTT. I was a signalman on the Cambrian for a number of years and there were situations where you sometimes had to change plans at the last minute, due to late running, stock working, crew relief etc but we had the 100% surety of the token system.
There have been many accidents caused by signalman acting in haste, very few caused by signalman doing nothing. When I was at signalling school the instructor always said, "If in doubt, put your signals to danger and put the kettle on". In other words, stop and think what you're doing first.
 

BRX

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We can't be running about questioning everyone and with the belief that everyone isn't doing their job correctly.

No, but at the same time, there is some value in a system that allows people to point out things that others have missed when appropriate.

There was a case some time ago where someone died in an operation. Whatever the surgeons were trying to do, it wasn't working. A nurse was observing and could see that they had missed an alternative course of action which probably would have saved the patient's life. But they weren't able to say this, either because they felt they couldn't challenge the authority of the doctors or because the doctor woudln't listen to them.

In response to this and other incidents many emergency departments around the world now have a checklist system which they go through at the beginning of each operation (and safety has improved markedly as a result). Going through stuff verbally can be a good way of making sure simple things aren't missed by otherwise very competent people. It also provides an opportunity for others in the room to comment within a formal structure, so that the risk of valid concerns being ignored is reduced.

This checklist system was inspired by those within the aviation industry where the pilot and co-pilot go through various checklists verbally. They have to jointly verify that simple but vitally important things have been done properly.

Another case I have read about is a supposed "bermuda triangle" disappearance; some trainee pilots flying in formation with their instructor. The instructor mistook, visually, an island for another location and from that point on refused to take notice of the fact that certain things weren't making sense. All of the trainees were telling him that the compass bearing was wrong. But he decided that the error was with all of the compasses rather than that he'd got something wrong. Again, the system failed to allow others to effectively question the decision of someone who was competent but had made the kind of error that all humans are liable to make - not giving sufficient heed to information that contradicts what they have already decided is the correct course of action.

Of course, I'm limited in my ability to say how relevant all this is to the practicalities of railway operations.
 

30907

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The number of head-on collisions in this list of German railway accidents, even in recent times, is quite surprising.

https://en.wikipedia.org/wiki/List_of_German_rail_accidents

The list is instructive.

Warngau 1975 - which I remember being reported in the UK - signallers' misunderstanding, compounded by poor timetabling practice and absence of safety backup.
Schweinsberg-Culten 1972 in the DDR - driver error, fog.

Bad Bramstedt - driver error, radio based verbal authorisation system (the line is a Nebenbahn, with simpler operating requirements)

Hordorf near Magdeburg in 2011 - this one caused a real stir in Germany, as at the time PZB was not mandatory where linespeed for the route was 100km/h or lower.

It's worth pointing out that single line working on significant routes is much more common in Germany than here (and the Soviets singled a lot of DDR routes for war reparations), so I'm not sure the number of incidents was significantly higher.
 

fulmar

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what is the current procedure to authorise a UK driver to pass a signal onto a single line section at danger? Assume track circuited so no token or train staff.

In addition to modified working, this is from Section P2 of the Rule Book, "Working single and bi-directional lines by pilotman" which relates to situations when working by pilotman does not need to be introduced -

1. The signal or signalling equipment has failed or has been
disconnected
Working by pilotman is not needed on:
• lines where a token is provided and the driver has the token
• track circuit block lines or ERTMS lines if all the track circuits
relating to the affected portion of single line are clear.
2. A track circuit or signalling equipment has failed
Working by pilotman is not needed:
• on lines where a token is provided and the driver has the
token
• on bi-directional lines if trains are allowed to proceed in one
direction only
• on track circuit block or ERTMS lines if authorised in the
Sectional Appendix.
3. Level-crossing equipment has failed
Working by pilotman is not needed:
• on lines where a token is provided and the driver has the
token
• on track circuit block or ERTMS lines if authorised in the
Sectional Appendix
• on track circuit block or ERTMS lines if all track circuits relating
to the affected portion of single line are clear.
 
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EAD

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Hello again all - afraid work has kept me from commenting on the thread. Very interesting discussion around PoSA, in particular because in many ways it achieves the same goal as the Zusatz or Zs i.e. additional signals do in German practice. Thanks in particular for the kind words about my posts on the German signalling system.

I have a couple of things to add picking up various points made since I last posted (apologies for not calling out the various individual users).

1) This is a relay interlocked signalling panel set up, so everything is fully interlocked at mainline standards and it is fully track circuited. Most likely this is through axel counters (but I would need to check).

2) In standard operation as under any signalling system on a single line only one train can enter the section and clearly you can't signal another move into that section. Likewise if another train entered the section you would see it on the panel and signals would fall back to fail safe red for both trains.

3) I have spent some time looking through the (very Germanic i.e. long) signalling manuals governing all operations. It is quite complex, but in essence for any signalling move there is always a very clear responsibility to check step by step that a route is set and proved correctly. Normally this is automatic - you push to set the route and you will see all points move and confirm locked on the panel, then the signals will clear. Where there is any route that will not clear the signaller has to step through what is causing the problem and confirm that everything is in order - no train in section/last routed train confirmed out of section, points set and locked, no issues with level crossing on route, etc. It is quite detailed but it is clear that by the book there is a clear procedure to follow and this should never have happened as it would have been obvious within seconds there was a train in section already. Leaving speculation to one side, as with all such incidents the facts conspired against all concerned to lead to this tragic outcome.

4) In German practice main signals fall broadly into entry signals, exit signals and block signals. This makes quite a difference as to what a Zs signal means. In this case, if either train was signalled out of the station by Zs1 then this would apply as 40Km/h in the station area, i.e. until clear of the last set of points. Zs1 is there to cover the most common issues such as a lamp failure and if a track circuit has failed after last train passage. In any event, it has to be proved that there is an issue before it can be used. Most signals in Germany have a Zs1 built in to avoid the original written order procedure (though nowadays there is of course radio as well). Interestingly, given more recent use of centralised control in these cases signals are being equipped more with Zs7 which means travel on sight (a bit like UK practice) and be ready to stop short of any obstruction (max 40 Km/h), the logic being you cannot perform the on the ground checks you can in an older box to confirm the line is clear.

5) Some initial information from the on train data recorders is being leaked. Officially all that is confirmed is that all systems were functioning normal on the trains, however the train from Kolbermoor apparently left correctly and at the distant signal for the block signal at the level crossing before (based on its direction of travel) the level crossing, it received a 500Hz INDUSI for red aspect expected, which will have set off the braking curve on the system, was acknowledged and so it was slowing down to stop at the block signal. It was travelling at 55 Km/h at the time of the crash which is consistent with the braking for the signal. Now, two things here: a) this does not expressly say it left under a normal signal, but the implication is that it did and German forums are saying so and b) this is odd as any route would be set station to station and not to the block signal, so that may imply that it had fallen back to red as the other train had entered the section, but that makes no sense as that train would have had to pass 2 red signals to do so which would have been INDUSI armed. There other speculation on this is a level crossing fault, but that would not fit as the train in the other direction had left the halt and gone over the level crossing which was protected by the block signal...all odd and we need to wait and see.

6) The observations on high number of head-ons is I think overstating it a bit. The biggest issue has been that in the former DDR there was not full INDUSI on many such lines to protect a head-on. For years there was a plan to catch up and as has been said a view was taken around line speed to get this done in terms of cost v safety benefit. Since the more recent ones (as has been commented) it was ruled full PZB 90 would be rolled out on all such lines and it has been. There are however smaller Nebenbahn which work on a telephone block system - let's not get into that but of course that has very strict rules and brings with it its own risks and I can't say I am huge fan but a Nebenbahn has a technical definition in terms of speeds, simplified signalling, traffic etc.

EAD
 

ComUtoR

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No, but at the same time, there is some value in a system that allows people to point out things that others have missed when appropriate.

Its still the same with the railway. If I don't believe something is safe then I don't do it.

If the Signaller gives me an instruction and I didn't think it was safe I would refuse (and have done)

@EAD Many thanks.
 
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D1009

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5) Some initial information from the on train data recorders is being leaked. Officially all that is confirmed is that all systems were functioning normal on the trains, however the train from Kolbermoor apparently left correctly and at the distant signal for the block signal at the level crossing before (based on its direction of travel) the level crossing, it received a 500Hz INDUSI for red aspect expected, which will have set off the braking curve on the system, was acknowledged and so it was slowing down to stop at the block signal. It was travelling at 55 Km/h at the time of the crash which is consistent with the braking for the signal. Now, two things here: a) this does not expressly say it left under a normal signal, but the implication is that it did and German forums are saying so and b) this is odd as any route would be set station to station and not to the block signal, so that may imply that it had fallen back to red as the other train had entered the section, but that makes no sense as that train would have had to pass 2 red signals to do so which would have been INDUSI armed. There other speculation on this is a level crossing fault, but that would not fit as the train in the other direction had left the halt and gone over the level crossing which was protected by the block signal...all odd and we need to wait and see.
EAD, many thanks for this very helpful insight. On the day of the crash, I recall some BBC footage showing one end of the wreckage with Km marker 30.2 showing prominently, though I have no idea which end of the wreckage it was. Looking again at the cab ride video posted earlier you can see the back of a distant signal in the vicinity of Km 30.5. If this is where the INDUSI warning for the eastbound train occurred, wouldn't it have been too close to the crash site to make much difference?
 

ComUtoR

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For whatever reason the oncoming train was going a reported 100 kph.

Whatever happened the instant the second train entered the section a crash was almost inevitable.

Trying to figure out :

Why a second train was allowed to enter the section. Both the interlocking and procedures should have prevented this.

Why INDUSI may have slowed one train but not the other. Before either train got to the block signal it should have stopped both as the section was occupied.

If there was a fault why did it not (on the surface) fail safe and why was the fault not detected.

Where there was potentially human error.
 

AlexNL

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Why a second train was allowed to enter the section.
Perhaps the signaller made a huge mistake, and inadvertently gave the driver a Zs1 (PoSA)?

Both the interlocking and procedures should have prevented this.
I would expect the driver to protest if he sees that the points behind the signal at danger at Bad Aibling are pointing away from his train, while the signaller gives him an Ersatzsignal.

However, if those had not yet been set (maybe because the other train was not yet in the block?) then I can see the driver just obeying the Ersatzsignal.
 

455driver

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Regardless of how the authority is conveyed to the driver whether it be by phone/radio conversation or PoSA, to my mind it just cannot be right that if there is a failure of a single line system that the signalman can authorise a train into the section without recourse to anyone else or appointing pilotmen etc.
This sounds like an accident waiting to happen, which unfortunately it did.

I have done that (I had only been driving a couple of months) and after getting the authority (and repeating back) I said-
I am going to ask a silly question now but bear with me, have any trains passed your box in the last 10 minutes heading my way.

The siggy laughed and said-
No driver, the line is yours, all points and the flow indicator are set for you to proceed, the only problem is a signal power failure.

I just said-
Thank you for that but you cant be too careful.


I have to say temporarily isolating the TPWS, passing the signal and proceeding through the points onto the single line was just a little unnerving.

At no stage did I fell uneasy with any instructions given by the siggy in Ash Vale box.

I wouldn't have a problem doing it again either!
 
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ComUtoR

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The siggy laughed and said-
No driver, the line is yours, all points and the flow indicator are set for you to proceed, the only problem is a signal power failure.

I just said-
Thank you for that but you cant be too careful.


I have to say temporarily isolating the TPWS, passing the signal and proceeding through the points onto the single line was just a little unnerving.

At no stage did I fell uneasy with any instructions given by the siggy in Ash Vale box.

I wouldn't have a problem doing it again either!

100% agree. The first time we do anything after passing out or even when new rules (PoSA's etc) are introduced its a little unnerving. The bit in bold is why I have such confidence in the Signallers. I've seen the flow indicators, I know a Driver would have been sent to examine the line (which is also unnerving), I've seen the block instruments and yes you can even look out the window and check the points for yourself.

It's odd when things like this happen because the non industry people are surprised it can happen. We are too but it is something we all face every day and this kind of danger is a reality to us.

The first Driver to go through Bad Aibling after this will no doubt be nervous as hell but even if they got the Zs1 I guarantee they will still accept the signal.
 

nom de guerre

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This checklist system was inspired by those within the aviation industry where the pilot and co-pilot go through various checklists verbally. They have to jointly verify that simple but vitally important things have been done properly.

Of course, there have been several fatal air crashes caused by distracted/pressurised crews either not completing checklists, or in some cases, forgetting them completely.



3) ... but in essence for any signalling move there is always a very clear responsibility to check step by step that a route is set and proved correctly... it is clear that by the book there is a clear procedure to follow

Interesting and informative post - thanks.

Alas, human factors can defeat even the most rigorous procedures.
 

Llanigraham

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Its still the same with the railway. If I don't believe something is safe then I don't do it.

If the Signaller gives me an instruction and I didn't think it was safe I would refuse (and have done)

@EAD Many thanks.

And the TRB would read something like:
Instruction given to driver of..............to do whatever. Driver refused to carry out instruction. Control informed @ time"
--- old post above --- --- new post below ---
100% agree. The first time we do anything after passing out or even when new rules (PoSA's etc) are introduced its a little unnerving. The bit in bold is why I have such confidence in the Signallers. I've seen the flow indicators, I know a Driver would have been sent to examine the line (which is also unnerving), I've seen the block instruments and yes you can even look out the window and check the points for yourself.

It's odd when things like this happen because the non industry people are surprised it can happen. We are too but it is something we all face every day and this kind of danger is a reality to us.

The first Driver to go through Bad Aibling after this will no doubt be nervous as hell but even if they got the Zs1 I guarantee they will still accept the signal.

Don't worry, it even makes us siggies sweat too!
We're the ones who end up in Court!
 
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