Overspeed at Dauntsey, 12 August 2020.

[2HAP]

RAIB investigated an overspeed (117 mph in a 20mph zone) at Dauntsey on 12 August 2020. They have decided not to progress to a full investigation.

Basically, an emergency speed restriction (ESR) was altered in the time that the train driver had departed from Paddington and the time he arrived at Dauntsey. Network Rail had not informed the train's operator of the change until after the train had departed from Paddington. The driver had no way of knowing of the change until he approached the ESR, by which time it was too late to obey said ESR.

Overspeeding incident at Dauntsey, Wiltshire

Preliminary examination into an overspeeding incident near Dauntsey, Wiltshire on 12 August 2020.

www.gov.uk

Overspeeding incident at Dauntsey, Wiltshire​

Preliminary examination into an overspeeding incident near Dauntsey, Wiltshire on 12 August 2020.

At about 16:07 hrs on Wednesday 12 August, a Great Western Railway (GWR) service from London to Bristol travelled at around 117 mph (188 km/h) over an emergency speed restriction (ESR) of 20 mph (32 km/h), near Dauntsey, Wiltshire. This incident did not result in any damage or injury.

We have reviewed the findings of this preliminary examination and have decided not to carry out any further investigation of the incident. RAIB has previously made recommendations in our investigation into the similar incident at Sandy on the East Coast Main Line on 19 October 2018 (RAIB report 10/2019), which cover topics which are relevant to the incident at Dauntsey.

 

[ExRes]

With such a massive speed reduction/alteration being introduced perhaps a requirement for the signaller to place the last signal before the ESR at danger should be considered, I certainly remember being stopped and warned prior to 2010 in similar circumstances

 

[Gloster]

Trains were being stopped at a signal and warned until fifteen minutes before the incident, but this was lifted once the signage at the warning boards had been altered. My recollection is that (in my day) a member of PW staff would have been stationed at the first warning board with a flag to alert the driver to the change.

 

[Efini92]

Why was it left as an ESR for over 2 weeks?

 

[4F89]

Why was it left as an ESR for over 2 weeks?

Because it takes time to print them in the WON. Its still an ESR, until it becomes a TSR.

 

[Efini92]

The 27th was a Monday so it should’ve been in the WON on the 7th August.

 

[4F89]

The 27th was a Monday so it should’ve been in the WON on the 7th August.

Depending if in the main edition or the supplement. Electronic publication is easier than printed copies, as I suspect you know.

It still remains an ESR until published.

Now, in terms of why the board wasn't placed at braking distance is another matter. Or indeed a blanket GSMR broadcast. Many things could have prevented it.

 

[bb21]

ESRs do remain for a significant period of time sometimes. They shouldn't in most cases, but they do.

 

[theageofthetra]

Why was a GSMR emergency broadcast not used to advise of this massive reduction in line speed?

 

[alxndr]

It could also have possibly been avoided if the ATP had been chipped to update it with the fact that there was an ESR in force. Yes, it would a been a pain having to put it on and then off a few hours later when the restriction was lifted, but safety should come before convenience. If convenience was allowed to overrule safety on a regular basis then what sort of railway would we have?

 

[Darandio]

If convenience was allowed to overrule safety on a regular basis then what sort of railway would we have?

Trains rushing through speed restrictions at 97mph higher than they should be?

 

[westcoaster]

If the boards were erected correctly it IS still the drivers responsibility to obey these.
No excuse for disregarding it, even if they recieved no warning about it in the late notice case. As they can be introduced at any time without warning.

 

[Crossover]

If the boards were erected correctly it IS still the drivers responsibility to obey these.
No excuse for disregarding it, even if they recieved no warning about it in the late notice case. As they can be introduced at any time without warning.

From my reading of the RAIB report, it sounds like the driver saw it but it didn't register - possibly unsurprising at 125mph when it would have presumably flashed by in an insant. A short notice speed reduction of 125mph to 30mph is pretty severe and as a layman, it doesn't sound like due process was in place to deal with such an occurence

 

[edwin_m]

To me the issue is that the ESR had been in place for over a month without being converted to a TSR. If it had been then the ESR zebra board would have had to be reinstated when the restriction was changed, giving the driver a clue there was something different going on. That would still have left a possible gap in protection if an ESR was imposed and changed soon after, but perhaps less likely to be a problem because drivers wouldn't have had the chance to get accustomed to it.

Presumably also the change to a more severe ESR didn't involve moving the board, which might also have alerted the driver.

 

[westcoaster]

From my reading of the RAIB report, it sounds like the driver saw it but it didn't register - possibly unsurprising at 125mph when it would have presumably flashed by in an insant. A short notice speed reduction of 125mph to 30mph is pretty severe and as a layman, it doesn't sound like due process was in place to deal with such an occurence

Raib said:

When the driver saw the ESR warning board, he did not register that 30 mph had become 20 mph. However, he did notice the absence of any 125 board below the 20. He assumed this had become displaced, and after a momentary brake application, the train continued at speed for about 37 seconds, covering over one mile (1.6 km), until the driver was able to read the 20 mph board at the point where the ESR started. At this point the train was travelling at 117 mph (188 km/h). The driver then made a full service brake application. This reduced the speed of the train to around 105 mph (169 km/h) by the time it had passed clear of the affected section of line.

It says he assumed a board had become displaced, and started to brake. That says to me he knew something was amiss.

It will be down to the raib to determine the sequence of events, and the actions the driver took there after.

 

[Efini92]

To me the issue is that the ESR had been in place for over a month without being converted to a TSR. If it had been then the ESR zebra board would have had to be reinstated when the restriction was changed, giving the driver a clue there was something different going on. That would still have left a possible gap in protection if an ESR was imposed and changed soon after, but perhaps less likely to be a problem because drivers wouldn't have had the chance to get accustomed to it.

Presumably also the change to a more severe ESR didn't involve moving the board, which might also have alerted the driver.

That’s my take on it.
The original ESR should’ve been changed to a TSR but for whatever reason it was never published in the WON. It seems to be happening at a lot of places now where ESR’s are left on for weeks/months at a time.

 

[edwin_m]

It says he assumed a board had become displaced, and started to brake. That says to me he knew something was amiss.

It will be down to the raib to determine the sequence of events, and the actions the driver took there after.

He started to brake but not until seeing the start of the restriction, only reducing speed to 105mph, and reported the incident afterwards as a possible error in the signage.

RAIB are not investigating any further, as recommendations after a previous incident at Sandy also cover this one.

 

[alxndr]

He started to brake but not until seeing the start of the restriction, only reducing speed to 105mph, and reported the incident afterwards as a possible error in the signage.

RAIB are not investigating any further, as recommendations after a previous incident at Sandy also cover this one.

When the driver saw the ESR warning board, he did not register that 30 mph had become 20 mph. However, he did notice the absence of any 125 board below the 20. He assumed this had become displaced, and after a momentary brake application, the train continued at speed for about 37 seconds, covering over one mile (1.6 km), until the driver was able to read the 20 mph board at the point where the ESR started.

The driver did briefly brake after seeing the ESR warning board, but only briefly. I assume he started braking as a reaction to the sign being different, but then quickly came to the conclusion that the 125 board must have fallen off and stopped braking until he saw the commencement board and realised that it did apply to him as well. I can see how someone could manage to come to that conclusion, having been accustomed to seeing one set of arrangements for an extended period of time. It strikes me as being similar to instances where a signal is approach controlled and they start to expect it to clear, until the one day that the signal doesn't and they SPAD. Or perhaps needing a railway equivalent of a "new road layout" sign.

 

[TheEdge]

This is an issue that develops when ESRs are left on for weeks rather than either being removed or converted into TSRs. You get so used to passing ESR flashing boards for weeks on end and them never changing that you start to treat them as an TSR, so a change like this, although technically correct, would be very easy to miss as a driver.

The same goes for SPATEs left for months (if not years) on end, but thats a different rant.

 

[_toommm_]

The same goes for SPATEs left for months (if not years) on end, but thats a different rant.

What is a SPATE please?

 

[4F89]

Speed previously advertised terminated early

 

[Y Ddraig Coch]

What is a SPATE please?

Speed Previously Advertised Terminated Early.

 

[_toommm_]

Thank you both

 

[theageofthetra]

This is an issue that develops when ESRs are left on for weeks rather than either being removed or converted into TSRs. You get so used to passing ESR flashing boards for weeks on end and them never changing that you start to treat them as an TSR, so a change like this, although technically correct, would be very easy to miss as a driver.

The same goes for SPATEs left for months (if not years) on end, but thats a different rant.

Spot on. It's ridiculous that this is never sorted.

 

[JN114]

Speed previously advertised terminated early

Speed Previously Advertised Terminated Early.

Common Misconception - it doesn’t “mean” anything, it is a Backronym - dates from when the railway used telegraph to communicate such arrangements and were charged to do so per-character.

@pdeaves excellent website has a section on all the codes (known)

At some point in history, someone has made up the backronym to help remember it, and it’s stuck. But you shouldn’t find it described as such in formal publications.

 

[4F89]

I'd suggest a little read of the rules then.

More specifically,

Signals, handsignals, indicators and signs handbook, RS521

Published by RSSB

Section 8.1

Pretty formal that....

 

[JN114]

I'd suggest a little read of the rules then.

More specifically,

Signals, handsignals, indicators and signs handbook, RS521

Published by RSSB

Section 8.1

Pretty formal that....

I said it shouldn’t be, with emphasis placed on the word shouldn’t.

It wouldn’t be the first error in an RSSB publication, and I’m certain it won’t be the last.

- As to why it doesn’t make sense, the termination of a speed restriction is the geographical end of where it applies. If it were to truly “terminate early” then the T board would move closer to the commencement board.

I accept it has fallen into common use, but that doesn’t make it correct. The normalisation of such misconceptions without challenge is a bugbear of mine.

Anyway, semantic digression aside, if you publish a TSR in the WON it should have a start and end date. That’s why SPATE boards have to be left up for so long, otherwise you’ll get drivers reporting TSR boards missing and other such time wasting. It would need a massive change in philosophy on the application of TSRs and ESRs to get away from it unfortunately. I do agree with @TheEdge however that it’s not made easy for traincrew.

I’d also add that the process of getting ESRs onto the late notice is convoluted with too many steps in the chain.

 

[Sheridan]

As to why it doesn’t make sense, the termination of a speed restriction is the geographical end of where it applies. If it were to truly “terminate early” then the T board would move closer to the commencement board.

To continue the semantics a bit, early refers to time rather than distance so I would contend that it’s correct here, but agree the use of ‘terminated’ is confusing because, as you say, the termination is the physical end point of the restriction, and using ‘terminate’ in the backronym to mean that the restriction has been removed is slightly confusing.

Out of interest, if SPATE doesn’t stand for anything, why was it used? There must be a reason that combination of letters was chosen.

 

[LCC106]

For _toommm_ as correctly explained, it is indeed a speed previously advertised terminated early (ie terminated earlier than the date published in the WON) OR NOT IMPOSED. Therefore there may be occasions when you see a spate board when no temporary restriction signage has actually been set out trackside.

 

[seagull]

If, as a driver, your late notices show an ESR which has existed for a while of, let's say, 20/125 (basically 20 mph for freight, 125 for passenger), and you get to the ESR which unbeknownst to you has been altered since you received the notices, to a universal 20mph speed, then yes I can quite see how the incident occurred, especially if the warning beacon and board were in the same or similar position.
The argument could be made that in the absence of the higher speed board, it should be treated as the lower one, but routine is the enemy and probably led to the understandable confusion.