Incident at Loversall Carr (Doncaster) involving two freight trains (05/07/22)

[12LDA28C]

Is it grids for the single yellow or TPWS+ grids for the red?

Grids for the single yellow AFAIK although of course it relates to the red signal ahead. The OSS for the single yellow is set at a specific speed and if the train exceeds that speed, a TPWS activation/intervention is given.

 

[GC class B1]

Grids for the single yellow AFAIK although of course it relates to the red signal ahead. The OSS for the single yellow is set at a specific speed and if the train exceeds that speed, a TPWS activation/intervention is given.

Am I correct in thinking that the OSS loops for the single yellow should have initiated a brake application as the train was travelling at a speed significantly greater than 65 MPH. The speed must have been significantly more than 65 MPH at the OSS loops considering it was braking when passing the AWS magnet for the red signal D197. This is not considered in the report.

 

[12LDA28C]

Am I correct in thinking that the OSS loops for the single yellow should have initiated a brake application as the train was travelling at a speed significantly greater than 65 MPH. The speed must have been significantly more than 65 MPH at the OSS loops considering it was braking when passing the AWS magnet for the red signal D197. This is not considered in the report.

It would depend entirely on whether that specific signal was fitted with an OSS loop and what speed it was set to trigger at, I haven't read the report but was quoting what happens at other locations.

 

[Taunton]

The report in the usual RAIB way has little pointers for you to work out what they think.

The Fatigue Statement is 'endorsed by the managing director' (para 127). It then states at least 32 hours after consecutive nights (para 131c), which patently wasn't done for the day shift just interposed in all the nights (para 68 shift 5), nor other aspects in that list.

It's apparent that, while someone has previously gone through the OTDR records at leisure (para 162) and used the chance to give a reprimand to the driver because they once applied the brakes heavily, meanwhile the management rostering arrangements just regard the Fatigue Statement as a joke. Which makes one question how much grip the 'endorsement by the managing director' has on the operation of the business.

 

[Railsigns]

TPWS OSS loops on approach to a signal are only active when that signal shows a red aspect. TPWS doesn't check the train's speed at a yellow aspect.

It very occasionally happens that the distance between a signal and its outer OSS is greater than the signal spacing distance, which can make it appear that the OSS belongs to the signal on approach to the one it protects.

 

[newtownmgr]

This is not correct. I'm aware of many trains being brought to a stand by TPWS due to approaching a single yellow signal too fast.

Well I’ve never known it been a driver since long before TPWS was introduced.
would like to know what speeds they are set at to set off tpws over speed grids at yellow.

 

[tiptoptaff]

Well I’ve never known it been a driver since long before TPWS was introduced.
would like to know what speeds they are set at to set off tpws over speed grids at yellow.

They aren't.

TPWS does NOT activate on approach to a yellow. TPWS Interventions/activations on approach to Yellows are simply because the OSS or TPWS+ grids for the RED are on approach to the yellow, they are NOT for the yellow.

Simply, the grids may be before the yellow, but they're for the red.

 

[newtownmgr]

Is it grids for the single yellow or TPWS+ grids for the red?

But even they should be the other side of the signal to allow for breaking distance. They certainly are for the routes i work when breaking from high speed.
You also get occasions where there is a significant change in speed within a certain distance after a signal requiring over speed grids to be placed for the PSR between the signal over speed & the train stop grid at the signal.

They aren't.

TPWS does NOT activate on approach to a yellow. TPWS Interventions/activations on approach to Yellows are simply because the OSS or TPWS+ grids for the RED are on approach to the yellow, they are NOT for the yellow.

Simply, the grids may be before the yellow, but they're for the red.

Think you’ve miss understood what i was saying. I know of no locations where TPWS+ grids for a signal are placed before the previous signal as signal spacing is designed to allow a train to brake from line speed to stop between the one yellow & the red. As i Just commented those extra grids maybe for a psr. We have several locations on my route knowledge with tpws+ grids & they are all located after what would be the yellow. In fact one location we have 2 sets of tpws+.

As i said if they are before the yellow as a couple have claimed, what speed are they set at & what speed are they set at for the red as it implies a very low approach speed which can actually import additional risks.

Most locations with TPWS+ the first set are usually set at or just below line speed as you should be braking in most cases as soon as you sight/pass the yellow & the final set are usually set between 35 & 42 depending on location. Some maybe lower due to spacing tho & may even be after the associated aws magnet.

 

[DoubleO]

If you are referring to the over speed grids at the one yellow, they would not activate. The only ones that would be live are the over speed & train stop grids at the red. The only over speed grids that are live at all times are those for permanent speed restrictions/approaching stop blocks.

The spacing of signals should allow a train to pass a yellow signal at linespeed & allow sufficient braking distance to stop at the red. Obviously every company has a driving policy in place that dictates that you respond Positively at 2 yellows. For instance shut off power & coast etc

This is correct for 3 aspect signalling, but in 4 aspect signalling the service braking distance is from the preliminary caution signal (double yellow) to the red.

 

[357]

But even they should be the other side of the signal to allow for breaking distance. They certainly are for the routes i work when breaking from high speed.
You also get occasions where there is a significant change in speed within a certain distance after a signal requiring over speed grids to be placed for the PSR between the signal over speed & the train stop grid at the signal.

Yeah, that's all correct, but I've still never known a single yellow have any type of grids associated with it...

 

[tiptoptaff]

This is correct for 3 aspect signalling, but in 4 aspect signalling the service braking distance is from the preliminary caution signal (double yellow) to the red.

Beat me to it.

Several places between Paddington and Reading where this is the case

 

[DoubleO]

The normal speed for TPWS+ OSS is 65mph however as with all OSS installations there are huge variations. TPWS is only energised approaching a red. And I can think of several locations where the TPWS+ loops are installed before the previous signal. A lot of misinformation and misunderstanding coming through in this thread...

 

[newtownmgr]

Beat me to it.

Several places between Paddington and Reading where this is the case

Fair enough. Got 4 aspect on routes i work but where we do have tpws+ it’s not before the previous signal. Last time i worked to Padd we didn’t even have DRA let alone TPWS

 

[Grassthorpe]

The Loversall report is an interesting read, but it seems to leave one issue only partially addressed: Flashing Yellow aspects. The view after Colwich, emanating from senior operations management at Rail House in Crewe, was that the driver of the down express was “let down” by the BR and its application of the signalling principles associated with Flashing aspects.

The report acknowledges the changes in rules to supress the flashing aspects if the signal immediately in advance of the junction signal was at danger, but the driver of 4E11 did receive the flashing aspect sequence with the signal immediately beyond the junction at danger. I can only assume that as the layout at Loversall predates even Colwich, so Railtrack were not required to retrospectively apply the changes in the signalling standard in February 2002. It seems odd that such an important change in the standards after Colwich and again in Feb 2002, would not have been rolled out throughout the whole system irrespective of implementation date. There cannot be that many flashing yellow aspect junctions and I assume its just a software change.

Like the view emanating from Rail House after Colwich, I think the driver was let down by the system – a system that the Railway said needed changing in 2002!

The driver was well acquainted with the route and probably received the flashing aspects each time he drove a train through that junction. Had he not received the flashing aspects, like the 2002 standard required and, even despite his fatigued state, he would have thought this is odd and reacted accordingly.

Fatigue was not the only hand on the tiller on this near fatal journey.

 

[tiptoptaff]

There are a LOT of flashing aspect junctions.

 

[Railsigns]

Current standards still allow a flashing yellow sequence to be shown when the signal beyond the junction is at danger, providing certain criteria are met.

 

[newtownmgr]

All a flashing yellow indicates is that you have the route through the junction. They used to be installed at high speed junctions only but seem to be installed a lot at lower speed junctions these days where traffic is frequent. At the end of the day a yellow implies the next is red, whether it’s flashing or not.

 

[12LDA28C]

All a flashing yellow indicates is that you have the route through the junction. They used to be installed at high speed junctions only but seem to be installed a lot at lower speed junctions these days where traffic is frequent. At the end of the day a yellow implies the next is red, whether it’s flashing or not.

As you already stated, a flashing yellow certainly doesn't imply that the next signal is red, quite the opposite. Flashing yellows used to be installed at high speed junctions because the meaning of a flashing yellow used to be that the route was set for the highest speed diverging junction (where there was more than one route available). Nowadays a flashing yellow just means that the route is set through the junction (where they may be only one diverging route available).

 

[martin2345uk]

All a flashing yellow indicates is that you have the route through the junction. They used to be installed at high speed junctions only but seem to be installed a lot at lower speed junctions these days where traffic is frequent. At the end of the day a yellow implies the next is red, whether it’s flashing or not.

Pedantically a flashing yellow can never imply the next signal is red

 

[DoubleO]

Pedantically a flashing yellow can never imply the next signal is red

Correct, and an important point

 

[172007]

TPWS OSS loops on approach to a signal are only active when that signal shows a red aspect. TPWS doesn't check the train's speed at a yellow aspect.

It very occasionally happens that the distance between a signal and its outer OSS is greater than the signal spacing distance, which can make it appear that the OSS belongs to the signal on approach to the one it

Deleted

 

[Train_manager]

The report in the usual RAIB way has little pointers for you to work out what they think.

The Fatigue Statement is 'endorsed by the managing director' (para 127). It then states at least 32 hours after consecutive nights (para 131c), which patently wasn't done for the day shift just interposed in all the nights (para 68 shift 5), nor other aspects in that list.

It's apparent that, while someone has previously gone through the OTDR records at leisure (para 162) and used the chance to give a reprimand to the driver because they once applied the brakes heavily, meanwhile the management rostering arrangements just regard the Fatigue Statement as a joke. Which makes one question how much grip the 'endorsement by the managing director' has on the operation of the business.

It was an accident waiting to happen.

Will it change anything. No.

The driver will/or has been fired and the company will carry on.

Profit before safety.

 

[Surreytraveller]

Yes, there is ‘CIRAS’ - an independent industry body who will take forward legitimate safety concerns and investigate on behalf of the informer. However, they will only become involved if all other safety avenues within the organisation have already been exhausted, which still requires a whistleblower to go down those avenues first.

Didn't realise CIRAS still existed. Haven't seen anything about them for years

 

[FrodshamJnct]

Hmm, interesting, section 39 does indeed seem to contradict section 52:

39 The driver made two further train brake applications, which had reduced the train’s speed to 54 mph (86 km/h) at the point they acknowledged the AWS warning for signal D197 (in 0.5 seconds). Witness evidence, forward-facing CCTV and OTDR data show that the driver made a full train brake application at a point when both signal D197 and the flashing taillight on the rear of 4E82 were visible

52 Train 4E11 was travelling at 65 mph (104 km/h) when the driver acknowledged the AWS warning for signal D197 (which was displaying a red aspect). The AWS magnet is located at the same position where signal D197 first comes into the driver’s view. GBRf requires drivers to control the speed of trains so that they are travelling at no more than 10 mph (16 km/h) when the train passes over an AWS magnet on the approach to a signal displaying a red aspect.

I contacted RAIB about this apparent contradiction, and have received the below response, confirming there was an error in paragraph 52. The report has been updated accordingly.

Thank you for your e-mail and interest in the work of RAIB.

There was a typing error which resulted in the wrong speed being referenced within paragraph 52. The correct speed of 54 mph was stated in both figure 5 and paragraph 39.

The report has been amended to reflect your comment

 

[greyman42]

I contacted RAIB about this apparent contradiction, and have received the below response, confirming there was an error in paragraph 52. The report has been updated accordingly.

You would of thought that this type of report was checked for typing/grammatical errors before being published!

 

[godfreycomplex]

You would have thought that this type of report was checked for typing/grammatical errors before being published!

As long as you have people or machines made by people doing the writing and checking, these things will be inevitable

 

[Purple Train]

You would of thought that this type of report was checked for typing/grammatical errors before being published!

It's "would have thought", not "would of"

Nevertheless, agreed - it isn’t a good look.

 

[12LDA28C]

You would of thought that this type of report was checked for typing/grammatical errors before being published!

Loving the irony right here, excellent.