Lumo overspeed incident at Peterborough (17/04/2022)

[stephen rp]

I've not read too far back (or the full report), but am I missing something?

The train was slowed by a caution (or red?) aspect because it was going onto a 25 mph crossover (presumably preset). Then a certain distance from the signal the preset cleared the route, with a feather (or other indicator) and a green aspect. As this was some distance from the junction the train was able to accelerate to way more than the crossover speed.

Why not show a yellow aspect for the move?

 

[jfollows]

I've not read too far back (or the full report), but am I missing something?

The train was slowed by a caution (or red?) aspect because it was going onto a 25 mph crossover (presumably preset). Then a certain distance from the signal the preset cleared the route, with a feather (or other indicator) and a green aspect. As this was some distance from the junction the train was able to accelerate to way more than the crossover speed.

Why not show a yellow aspect for the move?

See post 280 and subsequent discussion.

 

[edwin_m]

The signalling hardware is still the same, yet both these incidents happened recently.

One other thing that has changed is the advent of the 80x series units, whose acceleration on electric power far outpaces that of anything that would have regularly approached that signal before. The report mentions that a HST would also have been pretty fast at the crossover if driven in the same way, but unlike the 80x it was probably not fast enough to be close to overturning.

Costs aside, what would be the pro's and con's, and is it technically possible, to have the JI flash...at least at some high risk locations?

There's a hazard there that the driver might glance at it during one or more "off" phases and conclude that they had got the unrestricted straight route.

 

[Railsigns]

There's a hazard there that the driver might glance at it [a flashing junction indicator] during one or more "off" phases and conclude that they had got the unrestricted straight route.

The details are a bit sketchy, but there apparently used to be junction indicators at Rugby whose lamps were momentarily extinguished in turn to create an animated effect. Not only did this emphasise the direction of the divergence (helpful where a signal had combinations of junction indicators that pointed in opposite directions) but unlike flashing lights, the lamps wouldn't all go out at the same time while the indication was active.

 

[berwicksfinest]

One other thing that has changed is the advent of the 80x series units, whose acceleration on electric power far outpaces that of anything that would have regularly approached that signal before. The report mentions that a HST would also have been pretty fast at the crossover if driven in the same way, but unlike the 80x it was probably not fast enough to be close to overturning.

Agreed the 803 will have far quicker accelaration,

HOWEVER the point I'm making is the Lumo is being pulled onto the "slow" so effectively the Driver must have the inkling something quicker is going by or something in Platform 3 is going before him (Green Banner in 3 is a give away) so why open her out, Experience says potter along, let whatever is going in front, go. And theory says he'll keep rolling

 

[TreacleMiller]

Agreed the 803 will have far quicker accelaration,

HOWEVER the point I'm making is the Lumo is being pulled onto the "slow" so effectively the Driver must have the inkling something quicker is going by or something in Platform 3 is going before him (Green Banner in 3 is a give away) so why open her out, Experience says potter along, let whatever is going in front, go. And theory says he'll keep rolling

He had no idea that was happening.

 

[Jimini]

He had no idea that was happening.

(S)he would have done if they read the signal correctly, is my understanding of the situation?

 

[TreacleMiller]

Correct. They saw the signal but the not the junction indicator. It's all in the report.

(S)he would have done if they read the signal correctly, is my understanding of the situation?

 

[edwin_m]

Correct. They saw the signal but the not the junction indicator. It's all in the report.

Indeed. And this was exacerbated because they were driving a high-performance train that was capable of accelerating in a relatively short distance to a speed where overturning was narrowly avoided.

 

[Jimini]

Correct. They saw the signal but the not the junction indicator. It's all in the report.

One and the same, no? Again, not being antagonistic, just curious.

 

[Purple Train]

The details are a bit sketchy, but there apparently used to be junction indicators at Rugby whose lamps were momentarily extinguished in turn to create an animated effect. Not only did this emphasise the direction of the divergence (helpful where a signal had combinations of junction indicators that pointed in opposite directions) but unlike flashing lights, the lamps wouldn't all go out at the same time while the indication was active.

That sounds like a good idea.

 

[MotCO]

The details are a bit sketchy, but there apparently used to be junction indicators at Rugby whose lamps were momentarily extinguished in turn to create an animated effect. Not only did this emphasise the direction of the divergence (helpful where a signal had combinations of junction indicators that pointed in opposite directions) but unlike flashing lights, the lamps wouldn't all go out at the same time while the indication was active.

A bit like the 'strobe' indicators on some modern (German?) cars?

 

[Railsigns]

One and the same, no?

The driver saw the main aspect (green light) but not the junction indicator (line of small white lights), both of which are elements of the same signal.

 

[Grumpy Git]

A bit like the 'strobe' indicators on some modern (German?) cars?

Pedant alert: they don't strobe, i think the term used is 'animated'?

 

[LAX54]

The driver saw the main aspect (green light) but not the junction indicator (line of small white lights), both of which are elements of the same signal.

So Driver error, although NR is seemingly taking some of the blame, so who should pay for Signalling alterations for the TOCs new stock ? The TOC should fund it 100% if they wish to buy faster accelerating trains.

 

[Dr Hoo]

So Driver error, although NR is seemingly taking some of the blame, so who should pay for Signalling alterations for the TOCs new stock ? The TOC should fund it 100% if they wish to buy faster accelerating trains.

Do the Lumo trains accelerate faster than LNER’s or Hull Trains’ 80x units?

 

[TreacleMiller]

Do the Lumo trains accelerate faster than LNER’s or Hull Trains’ 80x units?

No, they don't. 801s/803s are marginally quicker to accelerate but nothing meaningful unless youre hard accelerating the entire drive.

Acceleration is not the issue here either. The risk of a really bad overspeed is arguably greater due to increased speeds but that's the same throughout the network. I'm told by older hands than me that there was an increase in Spads etc. Which many put down to higher levels of acceleration on newer stock.

Here it appears the blind was super low, driver didn't see it or check for it. That has happened at other TOCs on other junctions and it's actively briefed against at my TOC.

One and the same, no? Again, not being antagonistic, just curious.

No they aren't the samething but still ultimately human error.

It will be very interesting to see if the GC incident was due to similar reasons (didn't see it) or if they genuinely didn't have the route knowledge.

 

[Signal Head]

The details are a bit sketchy, but there apparently used to be junction indicators at Rugby whose lamps were momentarily extinguished in turn to create an animated effect. Not only did this emphasise the direction of the divergence (helpful where a signal had combinations of junction indicators that pointed in opposite directions) but unlike flashing lights, the lamps wouldn't all go out at the same time while the indication was active.

What era are we talking about for that? I've never heard of that being done.
It's an interesting idea.

 

[Railsigns]

What era are we talking about for that? I've never heard of that being done.
It's an interesting idea.

The only reference I've seen to them was in a weekly operating notice from 1960 that mentions them being converted to ordinary junction indicators. I would love to find out more about them.

 

[Signal Head]

The only reference I've seen to them was in a weekly operating notice from 1960 that mentions them being converted to ordinary junction indicators. I would love to find out more about them.

Thanks. So that predates the SGE resignalling, meaning they'd have been worked from the original lever frame boxes.

 

[Railsigns]

Thanks. So that predates the SGE resignalling, meaning they'd have been worked from the original lever frame boxes.

Yes, the signals involved would have been installed under the LMS colour light scheme of 1939. The signalling notice for that work mentions nothing unusual about the junction indicators though.

 

[MarkyT]

The driver saw the main aspect (green light) but not the junction indicator (line of small white lights), both of which are elements of the same signal.

While I like position 1 and 4 Junction Indicators (JI) as clear long-range directional indicators, my personal opinion is that the other JI positions are not at all intuitive and the horizontal ones in particular (positions 2 and 5) seem easy to disregard against a background of horizontal elements of bridges, gantries etc. For complex signals such as P468, I prefer a hybrid approach where only positions 1 and 4 JIs are used, supplemented where necessary by an alphanumeric Route Indicator (RI), displaying line name abbreviations or platform numbers. In this case, a position 1 JI would be displayed for both left-turning divergences, with '1' or '2' illuminated in an associated RI to indicate the precise destination. This method is permitted in current standards I think, as long as all the divergences associated with the particular JI position are of a similar speed, which is the case at Peterborough.

 

[norbitonflyer]

While I like position 1 and 4 Junction Indicators (JI) as clear long-range directional indicators, my personal opinion is that the other JI positions are not at all intuitive and the horizontal ones in particular (positions 2 and 5) seem easy to disregard against a background of horizontal elements of bridges, gantries etc. For complex signals such as P468, I prefer a hybrid approach where only positions 1 and 4 JIs are used, supplemented where necessary by an alphanumeric Route Indicator (RI), displaying line name abbreviations or platform numbers. In this case, a position 1 JI would be displayed for both left-turning divergences, with '1' or '2' illuminated in an associated RI to indicate the precise destination. This method is permitted in current standards I think, as long as all the divergences associated with the particular JI position are of a similar speed, which is the case at Peterborough.

I would agree that The J3 and J6 indications, (suggesting turns of more than 90 degrees!) are not intuitive.

At Peterborough, where all the directions lead to a platform, why not have the indicators show the platform number instead (or as well) as the J1-6 "feathers".

 

[MarkyT]

I would agree that The J3 and J6 indications, (suggesting turns of more than 90 degrees!) are not intuitive.

At Peterborough, where all the directions lead to a platform, why not have the indicators show the platform number instead (or as well) as the J1-6 "feathers".

Indeed 3 & 6 have always looked very weird to my eyes. JIs have been preferred historically because they are long-range readable, >800m on approach. RIs, even the larger size ones, are not considered readable until about 400m away by contrast. Thus if RIs only are used then approach release from red for all the diverging routes must be delayed until the train is close enough for the driver to reliably read the alphanumeric display. The combination approach of JI+RI allows the driver to see they are diverging left or right on one of a collection of routes of very similar speed and the precise route set then becomes clear as the train gets closer to the signal. Even if a driver assumes wrong for the precise route, as all routes indicated by the particular JI are within a small speed margin of each other then there is no risk of significant overspeed.

 

[Ashley Hill]

You still wouldn't want the green at the top because that would put it further from the driver's eye level.

G/Y/R at the top,Y below. Reading P3. Associated theatre indicator behind it.

 

[Railsigns]

G/Y/R at the top,Y below.

Because it's ground mounted and therefore below driver's eye level. The signal we were discussing is above driver's eye level.

 

[Ashley Hill]

I just got the impression from some comments that it was not possible to have R/G at the top hence the photo.

 

[Sunset route]

I just got the impression from some comments that it was not possible to have R/G at the top hence the photo.

The red aspect where possible is always placed closest to the driver line of sight.

 

[swt_passenger]

… In this case, a position 1 JI would be displayed for both left-turning divergences, with '1' or '2' illuminated in an associated RI to indicate the precise destination. This method is permitted in current standards I think, as long as all the divergences associated with the particular JI position are of a similar speed, which is the case at Peterborough.

I think the combination of JI and RI is in use for up trains at Reading West since the rebuild and associated resignalling.

 

[12LDA28C]

I would agree that The J3 and J6 indications, (suggesting turns of more than 90 degrees!) are not intuitive.

At Peterborough, where all the directions lead to a platform, why not have the indicators show the platform number instead (or as well) as the J1-6 "feathers".

Drivers are trained to understand the meaning of Junction Indicators and what each one (1-6) means in relation to their divergence from the main route. They don't just learn positions 1 and 4 and guess the rest. A platform number would only be visible at a much closer distance to the signal than the JI.