Train derailment closes line between Aberdeen and Dundee

[royaloak]

Not wishing to speculate here

No not much!

[royaloak]

If the cause is known and straightforward I too am surprised that RAIB need to attend at all, let alone cause a delay in re-opening the railway, so perhaps there is more to the incident than is yet public knowledge ?

Well the experts on here have already posted the 'facts' so the RAIB could have saved themselves a trip.

[beast66606]

Please explain how that makes the back of the train go the wrong way?

 

The front bogie has gone the 'right way' the rest of the train hasnt!

 

I already have

 

Given that you've selectively quoted my reply, I assume you read ALL of the post - if you don't understand what I described then I'll happily explain it again for you..

 

I have no idea what happened but the photo implies the points were changed while the train was passing over them. Mechanical failure is the least likely, but not impossible, maybe the slide bar fractured, which leaves either the driver moved without authority or the signalman reset the road without checking if the train was still moving and/or clear of the points (possibly both of these as I've explained).

[Wheatley]

I saw an email relating to this incident which happened last night.

It said no recovery was to take place until it go light as RAIB were not attending until then!

What has the railway come to???.

It used to be get the job running as quickly as possible

 

No recovery taking place because RAIB were not attending, or RAIB not falling over themselves to get there because no recovery could take place until first light? That particular day a lot (all ?) of the available DBC recovery assets were dealing with the concurrent  SPAD/derailment/cable chop which shut the west side of Sheffield station or the failed freight on the S&C which ran out of wheelskates and man hours. 

 

Certainly a few years ago the RAIB "trained up" a number of NR staff (LOMs/MOMs and the like) to gather/preserve evidence on RAIBs behalf (whilst RAIB travelling to site etc.) for such type of incidents (e.g. no one killed or injured, just damage to rolling stock/infrastructure) so as to reduce the time taken to implement recovery and get the job going again sooner rather than later. Maybe that there aren't any suitably trained 'RAIB' LOMs/MOMs in this particular area, hence having to wait until RAIB 'in person' arrive on site

 

RAIB Accredited Agent. Several DTMs I know were signed up for this, the general consensus was that the additional hassle which resulted was not worth the effort and they would not be renewing their accreditation.

 

 

Please explain how that makes the back of the train go the wrong way?

 

The front bogie has gone the 'right way' the rest of the train hasnt!

 

As well as Beast's explanations, it's perfectly possible for a switch blade tip which is just within tolerance when the first bogie goes over it to be just outside tolerance when the second one goes over it after the weight of the front bogie has shifted along the switch/closure rail a bit.  

[iands]

 

RAIB Accredited Agent. Several DTMs I know were signed up for this, the general consensus was that the additional hassle which resulted was not worth the effort and they would not be renewing their accreditation.

 

Hi Wheatley,

 

Many thanks for the update re "RAIB Accredited Agents". I was unsure if they were "still in circulation" so to speak.

[meil]

As you say, because these points were mechanically worked no FPL is provided at the derailment site.

 

However there are places where mechanical signalling is still in use but the points have been converted to power operation. In such cases although the signalman may not have an FPL lever in their signal box, the points themselves do have an FPL.

 

It should also be remembered that while an FPL may help lock the points in a given position, unless it is locked by a track circuit or similar, then it does little to prevent the points levers being moved while vehicles are traversing them.

But the signal allowing passage over the cross-over should be interlocked with the point so that the point could not be moved with the signal ON. Which seems to imply the signal was put back to OFF whilst the train was within the crossing.

[The Stationmaster]

 

As well as Beast's explanations, it's perfectly possible for a switch blade tip which is just within tolerance when the first bogie goes over it to be just outside tolerance when the second one goes over it after the weight of the front bogie has shifted along the switch/closure rail a bit.  

 

Exactly so and it wouldn't be the first time it's happened.

 

As yet we don't know exactly what took place here but that is one of the possibilities and is not one I'd rule out when trying to establish the cause of a derailment on points. 

But the signal allowing passage over the cross-over should be interlocked with the point so that the point could not be moved with the signal ON. Which seems to imply the signal was put back to OFF whilst the train was within the crossing.

 

You seem to have confused your 'on' and 'off'.  If a relevant signal lever is standing normal and the signal is on, i.e. at danger, the interlocking would allow the lever working the point to be moved.  If the lever working the signal is standing reversed and the signal is therefore off the lever working the point will be locked in whatever position it is standing at.

[royaloak]

I already have

 

Given that you've selectively quoted my reply, I assume you read ALL of the post - if you don't understand what I described then I'll happily explain it again for you..

 

I have no idea what happened but the photo implies the points were changed while the train was passing over them. Mechanical failure is the least likely, but not impossible, maybe the slide bar fractured, which leaves either the driver moved without authority or the signalman reset the road without checking if the train was still moving and/or clear of the points (possibly both of these as I've explained).

 

 

 

Are you stating this as fact or just conjecture on your part to try and blame the driver again, something you do regularly without a shred of evidence to back up your opinion!

 

If what you describe had happened then only one or two wheelsets would have gone the 'wrong' way before the signaller pulled the points again directing the rest of the train the 'right' way, but that isnt the case is it.

 

If the driver had moved before the points had been reset at all the front of the train would have gone the 'wrong' way, the points would then have been moved and the rest of the train would have gone the 'right' way, IE the opposite to what has happened here!

Edited October 15, 2018 by royaloak

[Wheatley]

Detection on a semaphore disc reading through a pair of trailing points isn't necessarily infallible, there are a lot of mechanical and human factors which can confound it.

Edited October 15, 2018 by Wheatley

[lmsforever]

Saw a coach do something like this at Aylesbury in the sixties all hushed up and rectified in ten minutes luckily no derailment or injury ,glad that nobody hurt but looking at the track tbit messy.hat was a 

[beast66606]

Are you stating this as fact or just conjecture on your part to try and blame the driver again, something you do regularly without a shred of evidence to back up your opinion!

 

If what you describe had happened then only one or two wheelsets would have gone the 'wrong' way before the signaller pulled the points again directing the rest of the train the 'right' way, but that isnt the case is it.

 

If the driver had moved before the points had been reset at all the front of the train would have gone the 'wrong' way, the points would then have been moved and the rest of the train would have gone the 'right' way, IE the opposite to what has happened here!

 

Give some examples of your sweeping generality - happy for you to quote as many examples as you can find - or are you simpy making things up ?

 

No-one was hurt in this incident, I doubt either the RAIB, NR or Scotrail care what any of us think so your overly agressive attitude is unnecessary.

 

You did look at the photograph  ? - and notice that the front bogie has taken the crossover and the second bogie has either been derailed by splitting points or pulled off by the forces of one bogie on one line and the the other trying to take a parallel line, the second vehicle is on the track and on the wrong line.

 

if the crossover was reversed and train started moving, the front bogie passing over the points and taking the crossover and then the points were normalised exactly what is visible in the photo would happen - this could also happen because of mechanical issues as has been mentioned above (including by me, although from what I was told this was unlikely, but then that person (who works in the area of the incident) may be wrong as he wasn't on duty and was only relaying what he'd been told).

[beast66606]

https://www.gov.uk/government/news/derailment-at-stonehaven-aberdeenshire

 

Crossover set, signal cleared, train started moving, signal put back, points normalised under the train.

[beast66606]

I have no idea what happened but the photo implies the points were changed while the train was passing over them. Mechanical failure is the least likely, but not impossible, maybe the slide bar fractured, which leaves either the driver moved without authority or the signalman reset the road without checking if the train was still moving and/or clear of the points (possibly both of these as I've explained).

[LMS2968]

Smart @rse!

[Wickham Green]

Crossover set, signal cleared, train started moving, signal put back, points normalised under the train, signalman sacked.

[lmsforever]

Just seen on BBC News website the RAIB will not be making any further investigations into this accident as no  decisions can be  gathered ,so its all over and nobody is being pursued bit of anti climax in all.

[brigo]

Give the position of the signalbox at Stonehaven the view south is somewhat obscured by the station canopy. I guess the signalman would only be able to see a train when it is well into the platform area.

 

https://commons.wikimedia.org/wiki/File:Stonehaven_Railway_Station_03.JPG

 

In this situation how do the signalman and driver communicate, ie how does the driver let the signalman know he's in a position to use the crossover ?

 

Brian

[phil-b259]

Just seen on BBC News website the RAIB will not be making any further investigations into this accident as no  decisions can be  gathered ,so its all over and nobody is being pursued bit of anti climax in all.

 

The RAIB  do not 'peruse' anyone! - they are an investigatory body that have no power to prosecute.

 

What the RAIB are saying is they have not uncovered any shortcomings which need addressing. That doesn't mean nobody made a mistake - but that said mistake had already been considered within the industry and was adequately addressed by the current rules & regs as far as was practicable.

Edited November 2, 2018 by phil-b259

[iands]

 

In this situation how do the signalman and driver communicate, ie how does the driver let the signalman know he's in a position to use the crossover ?

 

Brian

Hi Brian,

 

I would suggest use of GSM-R radio if no lineside telephone (SPT) is available.

[phil-b259]

Give the position of the signalbox at Stonehaven the view south is somewhat obscured by the station canopy. I guess the signalman would only be able to see a train when it is well into the platform area.

 

https://commons.wikimedia.org/wiki/File:Stonehaven_Railway_Station_03.JPG

 

In this situation how do the signalman and driver communicate, ie how does the driver let the signalman know he's in a position to use the crossover ?

 

Brian

 

I believe the crossover is fitted with shunt signals to control facing moves. As to when the signalman knows the train is clear of the points, depending on the situation you can use visual observation, track circuits, horn / whistle codes or GSM-R radio. Local knowledge / instructions will determine what method to use.