Report of collision Bedford (Elstow) - 19/06/26

[Belperpete]

Bit if, due to eye movement / saccading the unconscious bits of the brain were feeding the conscious bit, made up data based on 'last input'. as described in the link, along with how to mitigate it (from RAF) , then he might not have seen a last minute change

I don't see the point you are trying to make. If he didn't see the last minute change of the junction signal from yellow to green, his last input would have been it at yellow. Which should have led him to expect the next signal to be at red.

 

[westcoaster]

A good driver teaching the route will point out potential read through sites, read across sites. There's only a couple on the whole line London to Sheffield, this is not one of them. As he made the move from up slow to up fast, at Bedford South junction, WH356 stepped to one yellow,

This should have told him that the 810 that just passed him up fast has not cleared the following section and stood out as unusual. Instead of keeping the acceleration and speed within limits preparing to stop next signal, it was full demand.

The next signal is on the crest of a hill climbing away and visible from the junction. But he just kept on accelerating, why ?, convinced himself that previous was green as normal received, does not explain why he didn't react to the oncoming Red.

As a driver of 38 years on the route, I am mystified .

I have my Hypothesis on what happened, and as someone who drives this route daily. I always treat the signal as single yellow (as taught by my DI) on all moves with the stepping up of the signals on either the down to up moves or the up to up moves.

 

[Belperpete]

I think the driver not reacting to the yellow on the junction signal is readily understandable. If he was accustomed to it stepping up at the last minute, and got momentarily distracted, he might well have failed to register that it didn't step up on this occasion. So he could well have expected the following signal to be off.

Likewise his failure to react quickly to the train ahead is understandable, if his brain refused to accept the situation.

But what I cannot understand is his apparent total failure to react to the red aspect. Even if he was expecting it to be off, you would expect some kind of reaction on finding it actually at red, and it failing to clear, even if it were too late to do much about it.

I can understand his routine cancellation of the AWS on the red signal, as he might still have been expecting a cautionary aspect following the train he knew was ahead.

The only plausible explanation I can think of for him apparently failing to notice the red aspect is him being distracted by something, either inside or outside the cab.

I can understand him being distracted by the need to keep his speed in check until the rear of the train was over the junction. How close would he likely have been to the red aspect and it's AWS by then? However, I assume that drivers don't look back to check that their train.is clear, that they estimate this while still looking forward ?

 

[edwin_m]

I can understand him being distracted by the need to keep his speed in check until the rear of the train was over the junction. How close would he likely have been to the red aspect and it's AWS by then? However, I assume that drivers don't look back to check that their train.is clear, that they estimate this while still looking forward ?

Going by Google the signal is over 500m after the end of the crossovers, so even if it was a 12-car unit (it was a 4) the train would not be close to the signal on clearing the crossovers. Some freight locos have a distance counter that can be set to the length of the train but I don't believe any passenger units do.

 

[Hairy Bear]

Don't think your connection to saccades and the raf are relevant in train driving.The head is relatively steady during driving. We are not looking for fast changing objects, The relevent signal was on a gantry, fixed, line of sight just a few degrees movement from his focal point. The red on the gantry was probably visible for some 12 secs, he was either distracted massively by something or has drifted off into another world but still subconsciously acknowledging the magnet, we"ll never know I fear.

 

[foggy69]

A good driver teaching the route will point out potential read through sites, read across sites. There's only a couple on the whole line London to Sheffield, this is not one of them. As he made the move from up slow to up fast, at Bedford South junction, WH356 stepped to one yellow,

This should have told him that the 810 that just passed him up fast has not cleared the following section and stood out as unusual. Instead of keeping the acceleration and speed within limits preparing to stop next signal, it was full demand.

The next signal is on the crest of a hill climbing away and visible from the junction. But he just kept on accelerating, why ?, convinced himself that previous was green as normal received, does not explain why he didn't react to the oncoming Red.

As a driver of 38 years on the route, I am mystified .

When a train makes the move that the 360 did from a standing start at Bedford, is it usual that it is right behind a fast that has just passed though.

If leaving Bedford as the fast train is passing, does this give enough time for the WH154 to clear to green with an AWS bell before the train starting from Bedford gets to it, or is it usual that it is maybe only still a double yellow on approach with the corresponding AWS warning, but the next signal, WH152 is always green as the fast is by now, half way to Luton.

 

[GordonT]

The only plausible explanation I can think of for him apparently failing to notice the red aspect is him being distracted by something, either inside or outside the cab.

Unfortunately like some previous accidents in which the drivers did not survive, Moorgate being one example, there is unlikely to be one compelling and definitive conclusion why the red aspect was missed.

 

[bramling]

Unfortunately like some previous accidents in which the drivers did not survive, Moorgate being one example, there is unlikely to be one compelling and definitive conclusion why the red aspect was missed.

It’s quite mystifying. At least Ladbroke Grove and Cowden had reasonably likely explanations, even if we can never be quite sure. Newton was a “start up” so straight away there’s the built-in distraction of the station duties.

One accident which I’m not sure has been mentioned, and had actually slipped my mind, was Severn Tunnel. This was another oddity, although I’ve always suspected it was ominous that there were signal engineers working on the axle counter at the time, it’s too coincidental for comfort.

Certainly we can go back to Moorgate for one which has never been fully explained, although even there it could be explained if the driver completely lost consciousness in some way but was still somehow able to hold the handle down.

One presumes that if there was an obvious distraction (for example some kind of alarm or warning gone off in the cab just at the wrong time, or whatever), RAIB would probably have mentioned it by now.

 

[Belperpete]

It’s quite mystifying. At least Ladbroke Grove and Cowden had reasonably likely explanations, even if we can never be quite sure. Newton was a “start up” so straight away there’s the built-in distraction of the station duties.

One accident which I’m not sure has been mentioned, and had actually slipped my mind, was Severn Tunnel. This was another oddity, although I’ve always suspected it was ominous that there were signal engineers working on the axle counter at the time, it’s too coincidental for comfort.

Surely the Severn Tunnel accident was in part due to the signal engineers resetting the axle counter? It is why all subsequent axle counter installations have elaborate reset and restore controls, aspect restriction controls, etc etc.

 

[Hairy Bear]

When a train makes the move that the 360 did from a standing start at Bedford, is it usual that it is right behind a fast that has just passed though.
If leaving Bedford as the fast train is passing, does this give enough time for the WH154 to clear to green with an AWS bell before the train starting from Bedford gets to it, or is it usual that it is maybe only still a double yellow on approach with the corresponding AWS warning, but the next signal, WH152 is always green as the fast is by now, half way to Luton.

Yes as a rule the express has long gone and signals step up to a green, just occasionally 2 yellows. Wh346 only clearing to 1 yellow and staying such is rare and would have stood out, the driver altering his technique of powering through the crossover watching for the next signal.

 

[AHBD]

Don't think your connection to saccades and the raf are relevant in train driving.The head is relatively steady during driving.

But the brain 'making stuff up' is while eyes move (and visual input ignored during the saccade(s)?) not the head itself?

 

[josh-j]

But the brain 'making stuff up' is while eyes move (and visual input ignored during the saccade(s)?) not the head itself?

We're talking about very short duration stuff there though, and it's not exactly making stuff up, as far as I understand from a quick look at Wikipedia, it's backfilling (in your perception) what you see when your eyes stop moving into the time period where your eyes were moving.

It's not like this would mean you look at a red signal and see it as yellow just because your eyes moved to look at it.

 

[WAO]

The drawbacks of course was that it meant that drivers had to assume that the following signal would be at red, which often meant slowing unnecessarily. Or drivers becoming accustomed to the following signal not actually being at red. This arrangement is therefore no longer used in modern installations.

I think that describes the situation exactly.

A single yellow used to mean that you passed it at perhaps 25/30mph, ready for a red, which came into view long before action was needed. But at Elstow, the Ladder speed is 55mph, after which the next signal may be in view for possibly distracted seconds. And it passed a risk assessment!

I just wish the driver had moved back, out of the cab.

WAO

 

[Hairy Bear]

Every single junction movement carries a risk, judgement by the Driver at each junction regarding his speed is done as per his route knowledge.

Personally upon receiving one yellow at Bedford South, speed would be no more than 40 even though it's a 50mph movement as your focus is then switched to the next signal. But we're not talking a few seconds here,more like 12 to 20. He was massively distracted/ unresponsive.

I too wish also he had moved out the cab, my heart sank when I found out he made no attempt.

 

[bramling]

Surely the Severn Tunnel accident was in part due to the signal engineers resetting the axle counter? It is why all subsequent axle counter installations have elaborate reset and restore controls, aspect restriction controls, etc etc.

It was never really proven one way or other. Very suspect that technicians were present on the system at the time though.

 

[ADIRU]

I agree that areas of investigation should not be dropped at this stage, but it is also important the investigation not just focusing on immediate chain of technical events, but also the hidden link in systematic and human factors

Eastern Air Lines 401 [1] is a good example. During the descend, when pilot extended the landing gears, the landing gear indicators did not show locked. The pilot went on investigating the landing gear, got distracted and crashed.
It turned out to be a burnt light bulb at the cockpit, but the conclusion of the investigation wasn't "a burnt light bulb took down the plane". It was in fact cited pilot errors, and the underlying causes were poor crew resource management and company procedures.

Same for here, surely the reason for the AWS error and how the class 810 reacted to it warrant further investigation, it must be noted that all protection designed for this fault case was in effect, and why such protection hasn't actually prevented the accident should be discussed. The issue with class 810 must not be closed, but I expect to see investigation on driver training on AWS acknowledgement and interviewing drivers from different TOCs on this procedures.

[1] https://en.wikipedia.org/wiki/Eastern_Air_Lines_Flight_401. There is a good Mayday episode too.

TriStar aircraft had an autopilot setting known as 'Control Wheel Steering' and in this case, there was probably an unintentional slight push applied to the control column by one of the pilots which put the aircraft into a slow descent.

Whilst fault finding the landing gear and in the absence of 'Ground Proximity Warning Systems', the aircraft descended unnoticed until it crashed in the Everglades.

This was one case discussed many years ago in the aviation industry when we Flight Crew started to consider Human Factors and Crew Resource Management.

It is good to see that the rail industry (like the medics) has followed aviation down the road of Human Factors and things like managing distractions amongst many others.

 

[baz962]

A good driver teaching the route will point out potential read through sites, read across sites. There's only a couple on the whole line London to Sheffield, this is not one of them. As he made the move from up slow to up fast, at Bedford South junction, WH356 stepped to one yellow,

This should have told him that the 810 that just passed him up fast has not cleared the following section and stood out as unusual. Instead of keeping the acceleration and speed within limits preparing to stop next signal, it was full demand.

The next signal is on the crest of a hill climbing away and visible from the junction. But he just kept on accelerating, why ?, convinced himself that previous was green as normal received, does not explain why he didn't react to the oncoming Red.

As a driver of 38 years on the route, I am mystified .

Wasn't there a train waiting on the Down slow , which would make you lose sight of WH154 for a while.

 

[starlight73]

Maybe this is what you’re thinking of? There was a train held at the same gantry as WH356 (the single yellow signal) on the down slow (edit: clarification that this line normally travels away from London but here is bidirectional)

60. The West Hampstead signaller had received a report of a loss of power to overhead line equipment (OLE) in the area of Bedford South Junction. The signaller was unable to contact the drivers of either train 1H46 or 1B67. So, at 17:18, they contacted the driver of train 9T53, which had been held, facing southwards, at signal WH492 (on the same gantry as signal WH356 but for the Down Slow line, figure 2), to ask if they could see anything which would explain the power outage. The driver of train 9T53 responded that they could not see anything to explain the loss of power.

 

[sharpener]

Maybe this is what you’re thinking of? There was a train held at the same gantry as WH356 (the single yellow signal) on the down slow (away from London)

Is it usual for a train facing south (9T53) to be on the Down Slow or was it waiting to complete some manoeuvre?

 

[Spartacus]

Is it usual for a train facing south (9T53) to be on the Down Slow or was it waiting to complete some manoeuvre?

WH492's at Bedford South Jn, 9T53 would have likely come out of platform 2 & 3 and being held waiting for 1H46 to pass. I can't remember exactly now. It would have no impact on the visibility of any of 1H46's signals.

 

[Bikeman78]

They usually don't, but in some places (the A308 near Ashford for example) where the straight ahead and right turns have separate phases, they each have their own red, amber, and green-arrow lights.

In the Netherlands, if a green traffic light is an arrow then the corresponding amber and red lights are too.

 

[matchmaker]

Unfortunately like some previous accidents in which the drivers did not survive, Moorgate being one example, there is unlikely to be one compelling and definitive conclusion why the red aspect was missed.

You can go back a long way for such accidents - Harrow in 1952 being by far the worst.

 

[edwin_m]

In the Netherlands, if a green traffic light is an arrow then the corresponding amber and red lights are too.

That's so in many countries but there may be a risk of an arrow being perceived as a "go" even if it's red. Maybe the amber should be an arrow but the red remain solid.

 

[LCC106]

Edit: Deleted and reposted below to comply with forum quote rules.

 

[Hairy Bear]

@WAO As per the sectional appendix it is 50mph at Bedford South.

@Hairy Bear has the RAIB confirmed there was no attempt? I thought CCTV wasn’t able to be recovered for those few seconds before the collision.

To which bit of my previous posts
are you referring to ?.

 

[Efini92]

You can go back a long way for such accidents - Harrow in 1952 being by far the worst.

Harrow is different though as there was fog.

 

[LCC106]

@Hairy Bear
Apologies, my reply to the below would be to ask whether or not the RAIB has confirmed there was no attempt to move out of the cab, since the CCTV for those final few seconds hasn’t been recovered.

Every single junction movement carries …

I too wish also he had moved out the cab, my heart sank when I found out he made no attempt.

I think that describes the situation exactly.

A single yellow used to mean that you passed it at perhaps 25/30mph, ready for a red, which came into view long before action was needed. But at Elstow, the Ladder speed is 55mph, after which the next signal may be in view for possibly distracted seconds. And it passed a risk assessment!

I just wish the driver had moved back, out of the cab.

WAO

@WAO the speed according to the Sectional Appendix is 50, not 55, anlthough only a small difference.

 

[Hairy Bear]

My knowledge comes from someone at the collision site who confirmed he remained in his seat.

There is a large red button on the desk which puts the brake into emergency and opens the cab doors into the saloon. He had 9 seconds to do this, but didn't. There is internal CCTV on the cab door. Hitting that button and running through the coach shouting "Follow me" would get you into the next coach.

And yes, it's 50mph through the junction.

 

[WAO]

Didn't note my source for the speed but as the SA says 50, it's 50.
That still suggests a junction indication on the slow of double yellow or flashing yellow, rather than a true distant (for a red).
WAO

 

[Hairy Bear]

No, signak WH356 would have been 1 yellow and route indicator routing him out onto the up fast. CCTV and data logs proved the signalling system was working correctly. There are also no flashing aspects for this junction on this move.