RAIB Knaresborough derailment report published

[theblackwatch]

The RAIB report on the derailment at Knaresborough last November, originally discussed here, has been published, see https://www.gov.uk/government/news/report-162016-derailment-at-knaresborough

Summary

At 07:22 hrs on 7 November 2015, a Northern Rail passenger service from York to Harrogate derailed on a set of points on the approach to Knaresborough station. The train consisted of two class 150, 2-car multiple units.

The leading five bogies derailed and damage was sustained by both the train and track. None of the train crew or five passengers on board were injured. The line was re-opened at 12:58 hrs on 8 November 2015.

The signaller in Knaresborough signal box had authorised the train to pass a signal at danger (red), without realising that the set of points beyond the signal was in an unsafe condition. The signaller had not checked the associated points position indicator in the signal box and misinterpreted the significance of being able to reverse the signal lever, leading him to believe that the route was correctly set and safe.

 

[Marklund]

A simple check position on the lever at the B and D positions could have prevented this.
It's a shame it's been blandly covered in sections 74 and 75.

No Normal or Reverse detection when moving the points on a frame with checks?
Signal lever isn't coming out of the frame.

Quite disappointed in that report, considering the time spent looking at dry slide chairs.

 

[John Webb]

Surely if the signaller/MoM had glanced at the repeater for points 3 (see photo on page 12, para 16) when the signal failed to clear he could have realised that points 3 had not worked properly, and that was likely to be the problem?

 

[Marklund]

Indeed, but why have a lever release from the frame if it's not safe to do so?

 

[bramling]

Surely if the signaller/MoM had glanced at the repeater for points 3 (see photo on page 12, para 16) when the signal failed to clear he could have realised that points 3 had not worked properly, and that was likely to be the problem?

I suspect that had the indicator had a visual indicating "out of correspondance" or similar then he would probably have twigged what the issue was. The trap was that the indicator would have been blank, so if he didn't specifically look at the indicator there wasn't anything to draw attention to the blank indication.

It's quite easy to see how this, combined with the incorrect understanding of what the lever was (or in this case wasn't) proving, led to the incident.

In many ways I feel for the signaller here - we've all been in a position somewhere along the line when we've developed an incorrect understanding of how a piece of equipment works. The training and competence management process should pick up such misunderstandings.

 

[lincolnshire]

I bet the MOM wished he had stuck to his points duty at Harrogate instead of volunteering to cover Knaresborough box. His biggest problem at Harrogate was of getting very wet that day as it rained most of the day.

 

[Class 170101]

It will be interesting to see what this does to the idea of other ROCs controlling areas other than their usual control area in the event of issues at the usual ROC.

 

[GB]

It will be interesting to see what this does to the idea of other ROCs controlling areas other than their usual control area in the event of issues at the usual ROC.

Theres never really been a recognized or substantiated plan for this anyway has there?

Wishful thinking more than anything.

 

[LAX54]

It will be interesting to see what this does to the idea of other ROCs controlling areas other than their usual control area in the event of issues at the usual ROC.

AS GB says, don't think there was ever a true belief that that would ever happen, or be allowed, and as for ROCs themselves, most are now on hold, and boxes that are going into them were already too far down the line to call a halt, so now with the 30+ sub-ROCs things might be more 'workable'......IF they get off the ground too !

 

[edwin_m]

It will be interesting to see what this does to the idea of other ROCs controlling areas other than their usual control area in the event of issues at the usual ROC.

Nothing whatsoever. The issue here is an unusual feature related to the hotchpotch of mechanical and electrical interlocking at this box, which the person acting as signaller either didn't know about or had forgotten. It wouldn't have arisen had the interlocking been entirely mechanical or entirely electrical, and ROCs won't control mechanical interlockings.

There are plenty of other concerns regarding lack of local knowledge if ROC staff were to operate an area they weren't familiar with, but this isn't one of them. I suspect the ROCs won't have either the staff or the equipment spare to operate outside their normal area, and the most that can be expected if a ROC is totally lost would be is some sort of temporary location brought into use in a matter of hours or days. Crucially it would be worked by the staff normally based at the original site who wouldn't have anything to do otherwise, thus resolving the local knowledge issues as well as minimising cost.

 

[Signal Head]

A simple check position on the lever at the B and D positions could have prevented this.
It's a shame it's been blandly covered in sections 74 and 75.

No Normal or Reverse detection when moving the points on a frame with checks?
Signal lever isn't coming out of the frame.

Quite disappointed in that report, considering the time spent looking at dry slide chairs.

I thought that, too. However check, or indication locking wasn't usually provided on the former Eastern Region (BR), as long as the detection was proved in the aspect, whereas on the LMR it was virtually universal.

 

[nickleics]

Quite disappointed in that report, considering the time spent looking at dry slide chairs.

The new(er) format of RAIB reports, rather than the more old-fashioned investigations written as a letter and in the first person to the relevant government Minister, are something of a mixed blessing.

Now that everything's written in the third person, and with all individual names removed, there's a certain dryness to the reports. In some ways, this is an improvement for the lay-person, because I find that these newer reports tend to assume less prior knowledge and introduce often complex topics more thoroughly.

On the downside, there is a lack of a narrative and simple humanity arising from such an impersonal approach, and as such, the reader can never have a true understanding for where the writer(s) are coming from. In this case, a more opinionated 'voice' - such as those expressed by some of the contributions to this thread - could be helpful in helping to drive change.

As it is, there are a series of relatively dry recommendations which, whilst technically sound and unlikely to offend anyone, might struggle to actually impact operational practice - which is surely the point of producing reports of these investigations.

 

[John Webb]

I worked for nearly 28 years in a safety-related part of the scientific Civil Service, though not associated with transport. The reports I had to write had to be framed in such a way that lay-people (ie MPs, ministers and others) with little knowledge would understand what I and my colleagues were trying to say to them.

I agree that there is some loss, perhaps, of the personal touch in the RAIB reports. But I believe they are well-constructed and draw attention to the principle matters that need to be seen to by the various parties involved in any incident.

With respect to nickleics's comment re 'where the writer(s) are coming from' I would suggest that the RAIB's objective that it "....independently investigates accidents to improve railway safety, and inform the industry and the public." to quote their website, explains quite adequately. Note in particular the use of the word 'public' - in Railway Inspectorate days their narrative reports were aimed specifically at the controlling Ministerial department and the railway community - the public were not considered at all!

Regarding Marklund's comment on the time spent looking at dry slide chairs, this was the principle equipment failure which led to the accident - if they'd been properly set up and adjusted, the points would have worked as they ought and not have stuck as they did!

 

[edwin_m]

Regarding Marklund's comment on the time spent looking at dry slide chairs, this was the principle equipment failure which led to the accident - if they'd been properly set up and adjusted, the points would have worked as they ought and not have stuck as they did!

However, the original failure wasn't a safety issue, the problem was how it was dealt with, and I agree with Marklund that the report went off on a bit of a tangent here. If there was an accident caused by, say, single line working after a train failure, then would we expect RAIB to take the train to pieces to work out why it failed ?

 

[Signal Head]

However, the original failure wasn't a safety issue, the problem was how it was dealt with, and I agree with Marklund that the report went off on a bit of a tangent here. If there was an accident caused by, say, single line working after a train failure, then would we expect RAIB to take the train to pieces to work out why it failed ?

I'm sure there is at least one 'blue book' MOT report where the cause of the train failure (which lead to a serious rear end collision involving the following train) was included in the investigation.

 

[edwin_m]

I'm sure there is at least one 'blue book' MOT report where the cause of the train failure (which lead to a serious rear end collision involving the following train) was included in the investigation.

The reason for out of course working that leads to an accident is usually mentioned in passing, but was there a detailed investigation of the cause itself, with recommendations to make it less likely?

 

[Marklund]

Regarding Marklund's comment on the time spent looking at dry slide chairs, this was the principle equipment failure which led to the accident - if they'd been properly set up and adjusted, the points would have worked as they ought and not have stuck as they did!

Dry slides are a common problem.

Yes they were the root cause, and relevant to why there was degraded working, but the time spent looking at them was disproportionate to the real cause, (IMHO), why the MOM was lulled in to a false sense of security of a lever releasing from the frame, and the scant coverage of existing circuit design which would have prevented similar happening.

Considering the about of approach locking fitted after Moreton, it's surprising that similar circuit alteration wasn't recommended here. Again, it's just my opinion.