Wrong-side signalling failure at Wingfield

[baz962]

Not sure about how the actions of the signallers reduced the chance of a collision , but hey ho .

 

[Annetts key]

It seems like an obvious test would be to place a track circuit clip after the signal, and see if it turns red - is there a reason this isn't part of the procedure?

The already existing testing (for example the aspect test) should have detected this fault.
The aspect test requires that the tester (signal maintenance tester) confirms that the currently displayed aspect in the signal is compared to the expected aspect, the state of the control relays (or if computer interlocking, the control data) and the indication on the signallers panel/workstation (if applicable).

This test is carried out for every aspect that the signal is fitted with, including for any route or junction indicators.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==

How close can you get to recreating Clapham Junction without recreating Clapham Junction? Good grief that's a slightly chilling read in the summary.

You really don’t want to know about all the near disasters that Network Rail have discovered over the last five plus years, but through luck more than anything, did not result in anything bad happening. This has resulted in Network Rail returning to proper practical assessments in proper training centres for all of it’s own S&T engineering staff if they want to retain their Signal Maintenance Testing Handbook (SMTH) competence (this is what enables an S&T technician to be a signal maintenance tester).

 

[alxndr]

Not sure about how the actions of the signallers reduced the chance of a collision , but hey ho .

The signallers warning that something might be amiss (even if they initially surmised that the problem might be poor rail head adhesion) meant that the driver of the second train was approaching at a slower speed than would usually occur.

Para. 54 The signaller advised the driver to reduce their speed and expect signal DY584 to be at red. In response, the driver of train 1F02 maintained a speed of about 40 mph (64 km/h) and further reduced the train’s speed to 20 mph (32 km/h) after passing signal DY584 displaying a yellow aspect.

Para. 172 Once the driver was aware of a potential problem ahead, they had proceeded at a much slower speed than they might have otherwise, which greatly reduced the potential for a collision. Other drivers have remarked that it is common to pass a single yellow aspect at signal DY586 at a much greater speed, due to it being about 1.6 miles (2.5 km) until the next signal.

Ideally the signaller would have immediately clocked on to the fact that the driver of the first train was making an allegation against the signalling system, but nonetheless their actions to provide some warning is probably the reason why this was a near miss rather than a full-on accident. With the second train stopping just 75 meters from the first it already looks like there wasn't much room to spare.

It seems like an obvious test would be to place a track circuit clip after the signal, and see if it turns red - is there a reason this isn't part of the procedure?

The procedure doesn't specify exactly how the tests are to be performed (e.g. asking the signaller to operate the signal or slipping links) although this is taught and practised during training. The Signal Maintenance Testing Handbook is written to be generic and therefore applicable to the wide range of subtly different systems available.

In a track circuited area with automatic signals then you could command a signal to danger by placing a track circuit clip in the track circuit section after the signal, however, this track circuit section could be 200m away due to signal overlaps. If all other testing had been completed properly then this step would be completely unnecessary and essentially duplicating other testing that had already been performed. There were already numerous possibilities that would have highlighted this problem if the testing had been performed properly, adding one more, that would have likely taken more time to complete than some steps that had already been skipped (e.g. operating the Signal Post Replacement Switch) is unlikely to have had any impact. If someone is minded to skip the easy steps they're just going to skip the more ardous steps, especially if in their mind it's repetitive.

 

[baz962]

The signallers warning that something might be amiss (even if they initially surmised that the problem might be poor rail head adhesion) meant that the driver of the second train was approaching at a slower speed than would usually occur.


Ideally the signaller would have immediately clocked on to the fact that the driver of the first train was making an allegation against the signalling system, but nonetheless their actions to provide some warning is probably the reason why this was a near miss rather than a full-on accident. With the second train stopping just 75 meters from the first it already looks like there wasn't much room to spare.


The procedure doesn't specify exactly how the tests are to be performed (e.g. asking the signaller to operate the signal or slipping links) although this is taught and practised during training. The Signal Maintenance Testing Handbook is written to be generic and therefore applicable to the wide range of subtly different systems available.

In a track circuited area with automatic signals then you could command a signal to danger by placing a track circuit clip in the track circuit section after the signal, however, this track circuit section could be 200m away due to signal overlaps. If all other testing had been completed properly then this step would be completely unnecessary and essentially duplicating other testing that had already been performed. There were already numerous possibilities that would have highlighted this problem if the testing had been performed properly, adding one more, that would have likely taken more time to complete than some steps that had already been skipped (e.g. operating the Signal Post Replacement Switch) is unlikely to have had any impact. If someone is minded to skip the easy steps they're just going to skip the more ardous steps, especially if in their mind it's repetitive.

Didn't warn the 3rd train behind properly though. Only gave 1F01 a contact signaller message around Belper . For those not on the railway or unfamiliar with the rulebook as I know some people here will be and others not , a driver isn't required to stop or even respond to a contact signaller message on the move and can wait until the next stop . That next stop was Chesterfield and it's lucky the driver decided that as they were running on greens and slowing for the 80 at Ambergate that they decided to respond. That should of been an emergency stop and not a contact signaller message. Very nearly a third in the section and that would almost certainly be a collision.

 

[2HAP]

OK, I've read the whole of the report, and all posts in this thread. Something is bothering me.

Report states that driver of the first train had a series of greens, then encountered a (false) red and was unable to stop at the signal.

Given that a signal can revert to red at any time for any number of reasons, should the driver have been able to stop from first sighting the red at the speed they were legally doing?

 

[martin2345uk]

OK, I've read the whole of the report, and all posts in this thread. Something is bothering me.

Report states that driver of the first train had a series of greens, then encountered a (false) red and was unable to stop at the signal.

Given that a signal can revert to red at any time for any number of reasons, should the driver have been able to stop from first sighting the red at the speed they were legally doing?

Absolutely not, no. Braking distance is from the first cautionary aspect, to the red.

 

[baz962]

OK, I've read the whole of the report, and all posts in this thread. Something is bothering me.

Report states that driver of the first train had a series of greens, then encountered a (false) red and was unable to stop at the signal.

Given that a signal can revert to red at any time for any number of reasons, should the driver have been able to stop from first sighting the red at the speed they were legally doing?

Although different trains have different speeds the max linespeed around that area is 110 . An IC train takes a good mile plus to stop at those speeds. You would need a very long line of sight to do it. So in about 99.9% of instances no.
Anyway as you stated a red can revert anytime , what if it reverted when the train is 20 yards away.

 

[Annetts key]

I really do recommend people read the full report, all of it.

It’s mentioned, but there are no recommendations or learning points about the lack of lighting when the work on the signalling equipment was taking place. Despite Network Rail having previously decided that when detailed work on signalling equipment is being carried out, the lighting should be good enough that the staff should be able to see without difficulty (that includes lighting that does not result in strong shadows).

An experienced S&T technician, with adequate lighting, should have been able to tell the difference between the external wiring from the external cable and the smaller diameter internal wiring.

The report does include the very sensible comments that the industry must ensure that signalling testers understand the purpose of the tests and why they are required.

It’s also clear that there are still problems where the signalling testers don’t maintain independence from the work.

 

[skyhigh]

OK, I've read the whole of the report, and all posts in this thread. Something is bothering me.

Report states that driver of the first train had a series of greens, then encountered a (false) red and was unable to stop at the signal.

Given that a signal can revert to red at any time for any number of reasons, should the driver have been able to stop from first sighting the red at the speed they were legally doing?

As above, no. Trains are not driven on line of sight. A green indicates to the driver that the line ahead is clear. The drivers in this incident have done nothing at all wrong.

Signals are generally not replaced to red to stop trains in an emergency. That's what the GSMR emergency call function is for.

 

[LAX54]

Not sure about how the actions of the signallers reduced the chance of a collision , but hey ho .

the signaller on the Derby workstation at EMCC contacted the driver of the following train on the Down Main line, which was a passenger train that had just departed from Belper station. The Derby workstation signaller advised the driver of this train to proceed at a reduced speed as the train ahead had passed a red signal in the Wingfield area
At about 07:19 hrs, the passenger train approached the signal that the previous train had passed at red. The signal was now displaying a yellow (caution) aspect. After passing this signal at a speed of about 20 mph (32 km/h), the passenger train driver saw the taillights of the first train,

thus the train was only running at about 20mph.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==

OK, I've read the whole of the report, and all posts in this thread. Something is bothering me.

Report states that driver of the first train had a series of greens, then encountered a (false) red and was unable to stop at the signal.

Given that a signal can revert to red at any time for any number of reasons, should the driver have been able to stop from first sighting the red at the speed they were legally doing?

if you pass a green, then the ext signal is at the very minimum a single yellow, or in 4 aspect areas, double yellow.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==

As above, no. Trains are not driven on line of sight. A green indicates to the driver that the line ahead is clear. The drivers in this incident have done nothing at all wrong.

Signals are generally not replaced to red to stop trains in an emergency. That's what the GSMR emergency call function is for.

I'd argue pull up the signal to red, (if you are close by the button/lever) then send a REC call.

 

[Annetts key]

Signals are generally not replaced to red to stop trains in an emergency. That's what the GSMR emergency call function is for.

Signallers only put a signal to red “in front of” a train in an emergency situation. However, a failure of the signalling system can put a signal to red at any time, regardless or where any trains may be.

If the reason for stopping a train is not an emergency, if needed, signallers normally put a signal to red beyond the point where a driver will see a signal change aspect. Hence in a three aspect area, that would be three signals further on (train approaching the first signal did have a green and still sees a green, the following signal, unseen by the driver, changes to a single yellow, the next signal is the one that the signaller has put back to red). Hence the driver sees a normal sequence of signal aspects: green, single yellow, red.

Unless, the signaller can speak to the driver first, for example if they are already stopped at a station. Then after explaining to the driver, the signaller can put the signal to red.

 

[2HAP]

if you pass a green, then the ext signal is at the very minimum a single yellow, or in 4 aspect areas, double yellow.

And what if a trampoline blows onto the line and short circuits the track circuit? You get a red, don't you? AIUI, all a green signal does is give permission to pass. It says nothing at all about what is ahead.

 

[Annetts key]

And what if a trampoline blows onto the line and short circuits the track circuit? You get a red, don't you? AIUI, all a green signal does is give permission to pass. It says nothing at all about what is ahead.

All colour light signals convey information to a driver only during the time the driver can see them. So, at the time that the driver sees a signal showing green, at that time, the driver knows that the section of line ahead is clear and that they can proceed at the appropriate speed.

Once the driver is no longer able to see the signal, yes, anything can happen.

This is why when a driver sees an irregular signal aspect, they need to inform the signaller as soon as practicable. And the driver and signaller should keep an open mind and not jump to conclusions.

 

[baz962]

the signaller on the Derby workstation at EMCC contacted the driver of the following train on the Down Main line, which was a passenger train that had just departed from Belper station. The Derby workstation signaller advised the driver of this train to proceed at a reduced speed as the train ahead had passed a red signal in the Wingfield area
At about 07:19 hrs, the passenger train approached the signal that the previous train had passed at red. The signal was now displaying a yellow (caution) aspect. After passing this signal at a speed of about 20 mph (32 km/h), the passenger train driver saw the taillights of the first train,

thus the train was only running at about 20mph.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==



if you pass a green, then the ext signal is at the very minimum a single yellow, or in 4 aspect areas, double yellow.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==


I'd argue pull up the signal to red, (if you are close by the button/lever) then send a REC call.

I'm not talking about the train that departed Belper. There was an IC after that running at 100 while the other two trains were already in the section. It wasn't cautioned.

 

[Annetts key]

I'm not talking about the train that departed Belper. There was an IC after that running at 100 while the other two trains were already in the section. It wasn't cautioned.

What do you think should have happened then?

 

[baz962]

What do you think should have happened then?

You are joking. An emergency call perhaps or stop train message. Or was it ok to let it barrel on towards the first two trains. Or call the driver rather than send a contact signaller message.

 

[66701GBRF]

What 3rd train?

I also don’t believe there is any requirement or cause for signallers to send emergency stop messages to trains behind one that is reported to have passed a signal at danger. The signallers acted with the information they had at the time.

 

[Taunton]

Earlier discussion we had here, about the signal head being wired to the wrong aspects, or the colour filters being cleaned but replaced reversed, can now be seen inappropriate as the signal was a more modern LED single lens, multi-colour searchlight" type.

However, what I don't see in the report is the signallers having been advised that the signal had been worked on during the night, or even that test aspects had been worked through by a previous signaller at the end of the works. The subsequent signaller, when a train reported an incorrect sequence, PLUS information that the signal had been worked on during the night, should really have been advised of this to be able to put two and two together, given the number of previous issues after works (some mentioned in the report) to impact the subsequent trains then coming along.

 

[martin2345uk]

And what if a trampoline blows onto the line and short circuits the track circuit? You get a red, don't you? AIUI, all a green signal does is give permission to pass. It says nothing at all about what is ahead.

And if that were to happen it is highly unlikely the driver would be able to stop at the red if they were doing line speed, and would probably hit said trampoline.

 

[80073]

I'm not talking about the train that departed Belper. There was an IC after that running at 100 while the other two trains were already in the section. It wasn't cautioned.

Sorry to ask, but where is the reference to this third train in the Report? The RAIB doesn't seem to cover this in its conclusions.

 

[alxndr]

However, what I don't see in the report is the signallers having been advised that the signal had been worked on during the night, or even that test aspects had been worked through by a previous signaller at the end of the works. The subsequent signaller, when a train reported an incorrect sequence, PLUS information that the signal had been worked on during the night, should really have been advised of this to be able to put two and two together, given the number of previous issues after works (some mentioned in the report) to impact the subsequent trains then coming along.

The report suggests that they did contact the signaller prior to beginning work.

Para. 43 ... At 22:27 hrs, SMT1 called the Derby signaller and signed the affected signalling equipment out of use.

Their attempts at doing testing afterwards would also indicate to the signaller that something had been done during the night that would affect the signal, although how much of this would be recorded in the occurence book or passed on I don't know, signaller's rarely seem to be able to offer much detail unless they were the ones on shift at the time in my experience.

 

[baz962]

Sorry to ask, but where is the reference to this third train in the Report? The RAIB doesn't seem to cover this in its conclusions.

Why would it be. Luckily the driver called the signaller. If he hadn't he would of hit the second train and the driver didn't know exactly why he stopped. Held at Ambergate for an hour or so and then terminated at Chesterfield.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==

What 3rd train?

I also don’t believe there is any requirement or cause for signallers to send emergency stop messages to trains behind one that is reported to have passed a signal at danger. The signallers acted with the information they had at the time.

There was nearly a third train. My point is that an IC train was coming up on Wingfield at 100 mph after the incident. The signaller didn't attempt to stop the train and just sent a contact signaller message . So with two trains in a section already you don't need to stop a third heading towards that. Something needs to change then .

 

[80073]

Didn't warn the 3rd train behind properly though. Only gave 1F01 a contact signaller message around Belper . For those not on the railway or unfamiliar with the rulebook as I know some people here will be and others not , a driver isn't required to stop or even respond to a contact signaller message on the move and can wait until the next stop . That next stop was Chesterfield and it's lucky the driver decided that as they were running on greens and slowing for the 80 at Ambergate that they decided to respond. That should of been an emergency stop and not a contact signaller message. Very nearly a third in the section and that would almost certainly be a collision.

Why would it be. Luckily the driver called the signaller. If he hadn't he would of hit the second train and the driver didn't know exactly why he stopped. Held at Ambergate for an hour or so and then terminated at Chesterfield.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==


There was nearly a third train. My point is that an IC train was coming up on Wingfield at 100 mph after the incident. The signaller didn't attempt to stop the train and just sent a contact signaller message . So with two trains in a section already you don't need to stop a third heading towards that. Something needs to change then .

I'm just surprised that the RAIB is not as concerned as you rightly are. It's somewhat worrying that the RAIB doesn't appear to see the need for change.

 

[Taunton]

The report suggests that they did contact the signaller prior to beginning work.

Yes, and when finished, for testing. But was that passed on to the signaller who handled these first trains through the next morning?

 

[skyhigh]

And what if a trampoline blows onto the line and short circuits the track circuit? You get a red, don't you? AIUI, all a green signal does is give permission to pass. It says nothing at all about what is ahead.

I'm sorry but you're talking rubbish. The railway does not work on line of sight - the driver will not be expecting to stop at the next signal if they pass a green. If that were the case, trains would have to crawl around the network.

 

[AndrewE]

I'm sorry but you're talking rubbish. The railway does not work on line of sight - the driver will not be expecting to stop at the next signal if they pass a green. If that were the case, trains would have to crawl around the network.

Quite.
A Virgin Driver mananger (ex driver) once said to me "A green is an absolute promise to the driver that the line is clear."

It was after an investigation into why trains were losing time between Piccadilly and Stockport, apparently the signals never cleared to green but stayed on yellow(s?). It turned out that the signalmen were in the habit of not pushing the miniature levers fully back, which prevented a green showing, hence drivers going only as fast as would allow a stop at the red the signals were warning them of.

 

[Signal Head]

Quite.
A Virgin Driver mananger (ex driver) once said to me "A green is an absolute promise to the driver that the line is clear."

It was after an investigation into why trains were losing time between Piccadilly and Stockport, apparently the signals never cleared to green but stayed on yellow(s?). It turned out that the signalmen were in the habit of not pushing the miniature levers fully back, which prevented a green showing, hence drivers going only as fast as would allow a stop at the red the signals were warning them of.

That makes no sense at all, and there are no 'miniature levers' in that area.

What was found during the WCRM works, was that some of the Auto signals in the Down direction didn't provide full braking distance from YY to R. As this signalling dated from the original electrification around 1960, it had presumably been wrong since installation.

As a 'temporary' fix, the aspect sequence was adjusted so that some signals required a G on the next signal before they could show G themselves, which would lead to consecutive YY aspects, and I think there was a case of requiring the following signal 'Off' or approach TC occupied.

I have no idea if the situation was ever resolved, if so how (given that no signals have been moved), or if the 'temporary' controls are still applied.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==

Seems a rather similar scenario to Clapham, where the driver noted an irregular aspect and stopped at the next signal to report it. The first signal then gave a false proceed aspect to the following train.

Very similar in appearance yes. 'The railway', and all involved here have had a very lucky escape in my opinion.

 

[43066]

AIUI, all a green signal does is give permission to pass. It says nothing at all about what is ahead.

I think perhaps you’re confusing main aspect signals with shunt or subsidiary “calling on” signals.

A proceed main aspect means the line ahead can be assumed to be clear, and the worst thing that will be encountered is the next most restrictive aspect at the next signal. On greens you’d therefore typically proceed at line speed, absent a good reason not to.

A shunt/subsidiary signal (generally used in yards/depots/sidings, for mainline shunt moves, or for entering an occupied platform) means essentially “you have permission to pass, but should expect the line ahead to be occupied”.

 

[Tomnick]

Why would it be. Luckily the driver called the signaller. If he hadn't he would of hit the second train and the driver didn't know exactly why he stopped. Held at Ambergate for an hour or so and then terminated at Chesterfield.

== Doublepost prevention - post automatically merged: 23 Oct 2023 ==


There was nearly a third train. My point is that an IC train was coming up on Wingfield at 100 mph after the incident. The signaller didn't attempt to stop the train and just sent a contact signaller message . So with two trains in a section already you don't need to stop a third heading towards that. Something needs to change then .

Do you actually *know* what happened to the third train? I'm amazed that it's not been mentioned by the RAIB nor the ORR (who interviewed both drivers involved). From the signaller's point of view, there would've been no reason to suspect anything other than a (right side) reversion to danger in front of the ECS by the time 1F01 should've been passing Ambergate.

 

[baz962]

I d

Do you actually *know* what happened to the third train? I'm amazed that it's not been mentioned by the RAIB nor the ORR (who interviewed both drivers involved). From the signaller's point of view, there would've been no reason to suspect anything other than a (right side) reversion to danger in front of the ECS by the time 1F01 should've been passing Ambergate.

I do . Read my posts. I know the driver very well and was travelling with. Received a contact signaller message and decided to call signaller as running on greens and slowing down for the drop to 100 before the drop to eighty . Signaller was hoping for 1F01 to stop at next signal which wasn't possible and ironically might have been possible if requested or called , rather than waiting for the driver to call. They had cautioned the previous stopping service but didn't for the next non stop fast train. They also knew it might be something bad as a network rail employee that boarded 1F01 after finishing a night at Derby told us that something bad was going on , but not exactly what. So the signaller was concerned enough to 1. Caution a previous train . 2 . Try and get 1F01 to stop at the next signal , but not enough to send anything other than a contact signaller message. Also the two trains must have been in the section and not just the incident with the first train as it's a mere three or four minutes from Belper to Wingfield in a fast IC.
Just thought I would add that the driver didn't realise the exact problem until back in London and as he was stopped and no incident with that train had nothing to report. Very upset though , so probably no reason to be interviewed.