RAIB Report on Bletchley Derailment on 3/02/2012

[AntoniC]

The RAIB report has been released about the derailment @ Bletchley on 3rd Feb 2012.

The basic findings are :

1) The driver was speeding
2) The driver expected to continue on the normal route through Bletchley and wasnt expecting a diversion.

http://www.raib.gov.uk/cms_resources.cfm?file=/121121_R242012_Bletchley_Junction.pdf

Derailment at Bletchley Junction, Bletchley
3 February 2012

Summary

At 02:27 hrs on 3 February 2012, an electric locomotive that was being driven from Crewe to Wembley, on the West Coast Main Line, derailed as it negotiated the diverging route at Bletchley Junction. The locomotive was travelling at a speed of 65.5 mph (105.4 km/h) when it derailed: the speed limit for the diverging route was 15 mph (24 km/h). The driver received minor injuries and significant damage was caused to the underside of the locomotive, the track and the overhead electrification equipment.

The driver of the locomotive correctly reduced its speed on the approach to the red signal before the junction but when this changed to green, with an ‘F’ indication meaning that the locomotive was to take the diverging route, the driver applied full power in the belief that he was going straight on. It is likely that the driver only realised that he was to take the diverging route around the time he was passing the signal, by which time it was too late to prevent the derailment.

The RAIB found that the driver did not immediately observe and/or register what was displayed by the signal’s route indicator even though he understood its meaning. This was despite the fact that the approach view of the route indicator was found to be satisfactory, free of obstructions and with sufficient time for a driver to see and understand its meaning. The RAIB has concluded that the driver’s belief that he was continuing on the up slow line overcame the fact that the ‘F’ indication was clearly visible to him.

The RAIB has made one recommendation to Virgin Trains covering the training and assessment of drivers’ route knowledge, and two recommendations to Network Rail. The first of these relates to the assessment of the risk from overspeeding at diverging junctions when the signal before the junction clears from red to a proceed indication, and the second relates to clarifying the status of the Weekly Operating Notice, an operating publication which is issued to drivers, and which contained information about engineering work south of Bletchley requiring trains to take the diverging route at Bletchley Junction.

 

[fsmr]

The RAIB report has been released about the derailment @ Bletchley on 3rd Feb 2012.

The basic findings are :

1) The driver was speeding
2) The driver expected to continue on the normal route through Bletchley and wasnt expecting a diversion.

http://www.raib.gov.uk/cms_resources.cfm?file=/121121_R242012_Bletchley_Junction.pdf

Interesting read

Stupid question but why is an illuminated maximum speed sign not used as part of the route indicator as a back up to route knowledge where such a severe restriction is imposed?

Sure the driver should know the speed for that route but it is obviously not infaliable, a clear illuminated speed indication at the signal would have most likely prevented this as the driver was confused.

 

[wilsontown]

That doesn't sound like a bad idea to me actually, but I'm sure someone will be along shortly to explain why it can't be done...

Not sure if it would have helped in this case though, as it seems that the driver saw the route indication clearly enough, but just didn't really register it and acted as though he was continuing on the straight route.

 

[Tomnick]

A sign is (usually) provided at the point where the lower-speed route diverges, in addition of course to the Driver's route knowledge. Although indicating the speed at the signal sounds a good idea in principle, I suspect issues might include possible confusion with the alpha-numeric route indication itself, the fact that the speed restriction doesn't apply until the actual divergence and the possibility of providing too much information to the Driver at the signal itself.

 

[Searle]

What amazed me most about this case is that the driver was regularly speeding, even breaking the 60mph Temporary Speed Restriction through Bletchley station!

 

[A-driver]

Giving the speed on the signal wouldn't have done much here as the driver seemed not to register the route-it wasn't a case if him forgetting the speed limit.

All junctions with such a severe drop in speed are approach controlled so he would be brought down to a red then it would clear a certain set distance from the peg. This is to remind and warn if the drop in speed and try to avoid this kind if incident. Light locos are very nippy it seems so as far as I'm aware it then accelerated very quickly afterwards.

Sounds like end of a long night turn and just lost concentration-happens to us all from time to time but most of us are luckier and realise our mistakes before they pose a real problem.

 

[Ferret]

Sounds like end of a long night turn and just lost concentration-happens to us all from time to time but most of us are luckier and realise our mistakes before they pose a real problem.

He'd gone passenger up to Crewe and was driving the light engine to Wembley. A total lapse in concentration it seems was the root cause, but there seemed to be several elementary mistakes made throughout the journey.

 

[fsmr]

Giving the speed on the signal wouldn't have done much here as the driver seemed not to register the route-it wasn't a case if him forgetting the speed limit.

All junctions with such a severe drop in speed are approach controlled so he would be brought down to a red then it would clear a certain set distance from the peg. This is to remind and warn if the drop in speed and try to avoid this kind if incident. Light locos are very nippy it seems so as far as I'm aware it then accelerated very quickly afterwards.

Sounds like end of a long night turn and just lost concentration-happens to us all from time to time but most of us are luckier and realise our mistakes before they pose a real problem.

Hi
No i wasnt suggesting a fixed speed sign, i was thinking that on the peg with the route indicator, at the same time a digital speed read out could light up which obviously only lights when that route is set, which is already being done to give the route indication so IMHO would not be too difficult to do

 

[GB]

If the drivers concentration lapsed enough to effectively forget the route indication, his route knowledge and 50mph TSR then I don't think that having an illuminated speed sign on the signal would make much of a difference.

If you did have an illuminated speed sign on a signal, what would happen if that signal was a few hundred feet or more from the actual junction?

This was a extremely rare incident that was really only made possible by the fact it was a quick light engine. In most other circumstances this wouldn't have happened.

 

[the sniper]

Not this incident, but paragraph 107 highlights a separate scary incident:

107 On 30 November 2011, the driver of a class 390 train operated by Virgin Trains did not perceive the alphanumeric route indicator fitted to signal CE107 at Crewe. When the signal cleared to green, the driver assumed that he was to continue on the down fast line, which has a maximum permitted speed of 80 mph (129 km/h), rather than (unexpectedly) via platform 11 as indicated by the route indicator. The train accelerated from a speed of 24 mph (39 km/h) and traversed the junction at 59 mph (95 km/h) rather than the specified 20 mph (32 km/h).

108 Unlike signal BY19 at Bletchley, the view of the route indicator at signal CE107 was found to be partially obstructed by overhead line equipment at the point when the signal cleared, and to be degraded by sunlight. However, the factor of the driver’s expectation is similar in both cases; the route that the driver was expecting to take was not in fact the one he was actually to take.

I wonder how many passengers experienced that rocky ride?!

 

[tsr]

I wonder how many passengers experienced that rocky ride?!

I'd imagine there were at least a few very scared passengers after that!

I might not notice - I'm subjected to the delights of the points at Balham too many times per week...

 

[A-driver]

I find it very interesting to read in the report about his roster and the diagram he was working. Whilst I'm not going to comment on this exact case as I see no point I would say that it highlights one of the biggest challenges I find about the job and concentration. Let me explain...

It was his first night shift after a row of day turns. Realistically he wouldn't have properly slept. It's almost impossible to get further than a nap in the afternoon before the first night shift.

You then need to get into work. This may be by train for example so realistically you could spend up to an hour or so passing into work. You will start to find yourself getting a little tired and lethargic at this point.

You then book on and probably sit around in the mess room waiting for the pass train-this time yesterday you were unwinding waiting to go to bed. Your body wants to do the same now.

You then spend 2 hours passing to crew- I'm sure everyone reading this has got off a 2 hour train journey before and knows how it feels-slightly tired, takes a few moments to fully wake up.

You then get to the train, set it up and wait for the signal. As you start the journey you have spent 3-4 hours in the middle of the night travelling and sitting around not doing anything. Your body and brain wants to sleep as it is and so the long journey you have just had won't have helped. Then you are expected to spend 2-3 hours fully alert concentrating 100% on watching a needle on the speedo (if using speed set then possibly not even doing this much) whilst green lights flash past and every couple of mins you hear the 'ding' if the AWS. It's pitch black so you can hardly see anything. No matter how hard you try your mind is going to wander off onto other things. Whilst its easy to say you shouldn't go into auto pilot mode we certainly all do from time to time and the skill is snapping out of it before you do something wrong.

I have experienced this on night shifts (and some day shifts)numerous times and I just felt it worth posting. As I say I'm not specifically talking about this RAIB report in particular but a general observation about shift work, night shifts and diagrams with too much passing at the start. It does have a big effect on your driving and concentration and makes it very easy to miss things.