Scotrail 334 becomes uncoupled near Uphall (26/11)

[GB]

That would be 95% Signaller error then ! but ALL highly unlikely

Depends what the signallers actions are and what he says to the driver surely? If hes told the driver to examine the line and stop short of any obstruction then any resulting collision can't be held against the signaller.

I can't find the report but wasn't there an incident a few years back (somewhere up north I think) where a driver was instructed to proceed at caution following a report of a track defect but the train was then actually traveling to fast to stop short of said defect? I think the resulting upshot was there was no actual defined speed for proceeding "at caution".

 

[Lemmy99uk]

I can't find the report but wasn't there an incident a few years back (somewhere up north I think) where a driver was instructed to proceed at caution following a report of a track defect but the train was then actually traveling to fast to stop short of said defect? I think the resulting upshot was there was no actual defined speed for proceeding "at caution".

That was near Dalston on the Cumbrian Coast line and resulted in a derailment due to a buckled rail.

 

[GB]

That was near Dalston on the Cumbrian Coast line and resulted in a derailment due to a buckled rail.

Ah, thank you.

 

[Surreytraveller]

That would be 95% Signaller error then ! but ALL highly unlikely

It wouldn't be signaller error at all. All accidents are highly unlikely. But we still have accidents.

 

[Surreytraveller]

So the signal at the rear of the platform is red, as well as the signal at the front of the platform. Is there some fail safe in signalling which flags this type of situation as a danger or not?

This situation, the signalling wouldn't have failed safe, as the signalling wouldn't have failed as it is a situation the signalling is designed to protect against in normal working.

 

[Ken H]

That was near Dalston on the Cumbrian Coast line and resulted in a derailment due to a buckled rail.

there is another thread on here where a bloke is logging his driver training. I asked about driving and being prepared to stop at an obstruction and he said covered on day one.
But we see on the roads any dont know how to drive at a safe speed able to stop as far as they can see. So it probably hard for a driver, used to being told by signals that the line is clear, that he has to drive on sight.

 

[jamesst]

I once lost a unit on the line between two stations. They have reacted as planned (50% braking force for the leading unit, emergency brake from the trailing unit and the according fault message). Had to go on a walk to the second unit to attach it again.

Are you allowed to reattach units like that where you work? At my toc it's a big no no until a fitter inspects them

 

[driver_m]

I imagine the train probably wasn't attached properly in the first place. If it was, the emergency brakes would have been applied.
It would be unusual for several things otherwise to go wrong - a coupler failed; automatic brake failed (although it appears to have worked in the rear unit)

I use Alstom TMS on a pendo, I know the 175 family have the same TMS, so I'll take an educated guess that the 334 has the same TMS. Presuming that it uses the same sort of software, it would be showing all kinds of faults if a unit was to split in service. Crucially, it would also say that train had no tail lights if the middle ones were in the 'off' position. (Something we are required to do on any of our units with a non-end cab for this exact reason.) .It would also show the consist. Whether a 3,6 or a 9 car to enable monitoring of the systems in that rear set. As others have said, stop speculating on fault, you have no idea what has happened. It will come out eventually. But a divided train is perfectly safe as long as procedures are followed after declaring it. I hate it when this forum goes all AVherald and people start blaming left, right and centre without knowing what they're talking about.

(AVHerald is a superb passenger plane incident website that sadly has the most moronic comments from people trying to blame pilots, ATC and cabin staff for pretty much anything)

 

[380101]

VERY!!!!
It is something drummed into you from just about day one of your training.
You'd be banging out 9 and 4-5 almost immediately you noticed.

I managed to get from Kilmarnock to Dumfries after another a booked split in service, before a signaller called me up on the GSMR to say "you've nae tail lights son!". I had passed 5 manned signal boxes before getting to Dumfries! So, not always 100% observant!

 

[LAX54]

Depends what the signallers actions are and what he says to the driver surely? If hes told the driver to examine the line and stop short of any obstruction then any resulting collision can't be held against the signaller.

I can't find the report but wasn't there an incident a few years back (somewhere up north I think) where a driver was instructed to proceed at caution following a report of a track defect but the train was then actually traveling to fast to stop short of said defect? I think the resulting upshot was there was no actual defined speed for proceeding "at caution".

Yes you are correct, if the Signaller says be prepared... etc etc, then yes the onus moves to the Driver.

 

[LAX54]

Makes complete sense. The signalling system is not designed to ascertain that a train has left the section with the same number of vehicles as it entered with, only that a train is not detected within the section.

The signalling system detects the absence of a train (or individual vehicle), and if it cannot detect the absence of a train (or individual vehicle) then will protect that section by not permitting the clearance of the signal in the rear, or indeed any other signals with an overlap in that particular section.

Yes - Axle counters do detect the number of axles, however the number is only used to make sure the same number of axles leaves the section as did enter.

What Signal Head is pointing out, is that to ascertain the completeness of the train, the axles or vehicles would need counting out of the section, which is impossible unless the signal is already cleared...

Well..... showed the response to a number of Signallers, none of them know what the remark meant !

 

[bahnause]

Are you allowed to reattach units like that where you work? At my toc it's a big no no until a fitter inspects them

As a driver I have the traction knowledge. I look at the couplers and check them every morning when I prepare the train for service. I know what parts to look at and how they should look like. What's the point of showing me this stuff, when I'm not allowed to use my knowledge? It clearly says in our Rulebook:

If no competent maintenance staff is available, the driver is solely responsible for technical arrangements in the event of malfunctions or damage to the rolling stock.

(Might be a bad translation...)

What's the worst thing that can happen? It might not couple again -> Game over.

I use Alstom TMS on a pendo, I know the 175 family have the same TMS, so I'll take an educated guess that the 334 has the same TMS. Presuming that it uses the same sort of software, it would be showing all kinds of faults if a unit was to split in service. Crucially, it would also say that train had no tail lights if the middle ones were in the 'off' position.

All our rolling stock with automatic couplers will show us a clear message, that a uncommanded uncoupling happened. It has to be designed like this for safetey reasons.

 

[Erniescooper]

As a driver I have the traction knowledge. I look at the couplers and check them every morning when I prepare the train for service. I know what parts to look at and how they should look like. What's the point of showing me this stuff, when I'm not allowed to use my knowledge? It clearly says in our Rulebook:

If no competent maintenance staff is available, the driver is solely responsible for technical arrangements in the event of malfunctions or damage to the rolling stock.

(Might be a bad translation...)

What's the worst thing that can happen? It might not couple again -> Game over.


All our rolling stock with automatic couplers will show us a clear message, that a uncommanded uncoupling happened. It has to be designed like this for safetey reasons.

I had the the pleasure of working on 175 and all the Alstom trains of the same vintage follow very similar wiring principles. It can’t have been a mechanical failure as the drum switch in the rear cab must have rotated to the the coupled position as the front unit was able to release its brakes otherwise none of the safety circuits would be complete. The solenoids to rotate the drum switch and actuate the mechanical coupler head are both fed from the uncouple button but that is fed from a sets of contacts in a “Cab open” relay which being in the rear cab would not be picked up. I can only think the fault is a false feed on the uncouple circuit , maybe water ingress into a plug.
The driver wouldn’t have seen a coupling fault as such but as the electrical heads parted company the TMS would have reconfigured automatically from a 6 car to a 3 car as the data bus was lost on the trailing unit .

 

[robertclark125]

Apologies if this has already been answered, but in the incident at Uphall, with the front unit leaving the station, and the rear unit still in the station, how would the signalling work? With the front unit now occupying a new section, would the signal behind have still showed a red aspect, due to another unit being in the section still, or would it have showed a caution aspect, signifying the next signal was at danger?

 

[philthetube]

If track circuited, then would still show occupied but the signaller would beging scratching head as the adjacent section would beoccilied too. If axle counter then obviousky less axles would be counted out compared to in and would show occupied. If old fashioned semaphore block, then front portion wouldn't (or shouldn't ) be hosting a tail lamp so signaller has to assume division of train.

If the train, thought, for whatever reason, that it was supposed to be uncoupled then wouldn't the tail lights illuminate automatically?

 

[Surreytraveller]

Apologies if this has already been answered, but in the incident at Uphall, with the front unit leaving the station, and the rear unit still in the station, how would the signalling work? With the front unit now occupying a new section, would the signal behind have still showed a red aspect, due to another unit being in the section still, or would it have showed a caution aspect, signifying the next signal was at danger?

The signalling would just see two separate sections that weren't clear.

 

[Surreytraveller]

If the train, thought, for whatever reason, that it was supposed to be uncoupled then wouldn't the tail lights illuminate automatically?

No. A taillight indicates a train is complete. That's why they have to be manually activated, so they cannot be switched on when they shouldn't be.
The purpose of the taillight isn't to prevent a train colliding from the rear, its to indicate to staff that the train hasn't divided.

 

[Crossover]

No. A taillight indicates a train is complete. That's why they have to be manually activated, so they cannot be switched on when they shouldn't be.
The purpose of the taillight isn't to prevent a train colliding from the rear, its to indicate to staff that the train hasn't divided.

On some (newer?) units isn't it an automatic process at the time of coupling? The likes of 185's seem to extinguish all "buried" lamps at point of electrical coupling

 

[snookertam]

There's a 15 minute service in each direction at Uphall, so has anyone been able to fathom how a train could sit there for 30 minutes and nobody realised?

In addition, there's CCTV on the station monitored from Dunfermline. Should it not have become apparent fairly quickly what had happened?

 

[LAX54]

Apologies if this has already been answered, but in the incident at Uphall, with the front unit leaving the station, and the rear unit still in the station, how would the signalling work? With the front unit now occupying a new section, would the signal behind have still showed a red aspect, due to another unit being in the section still, or would it have showed a caution aspect, signifying the next signal was at danger?

In the box it will show as a track circuit 'failure' after the 1st part had left, after moaning a bit, the Signaller will call fault control to report track 'ABC' was showing occupied when it should be clear, and that it was left 'down' after the last train left, he will then examine the line with the next train, who will either report, nothing seen, or maybe he has stopped at a broken rail, or even that he has stopped behind a train that is in his way ! The Signaller will NEVER assume its simply a track circuit failure, only the S&T can tell him of that. and of course there are a multitude of reasons a track can show 'occ' when it shouldn't,,,, a train being there, whilst rare, is just one of them !

 

[Erniescooper]

No. A taillight indicates a train is complete. That's why they have to be manually activated, so they cannot be switched on when they shouldn't be.
The purpose of the taillight isn't to prevent a train colliding from the rear, its to indicate to staff that the train hasn't divided.

The taillight feed also runs through the drum switch meaning that when you couple to a stabled unit with its taillights correctly illuminated and then press the couple button to electrically connect the units the drum switch will rotate and extinguish the taillights.

 

[30907]

If the stranded unit did not show on the track circuiting - leaves etc, or no track circuiting on that part of track, could the next train have had a green light, unless they have axle counters?

If there were no track circuiting, the train would be required to have a Guard whose primary role is to ensure the safety of the train by protecting it in rear in the event of its becoming disabled (I know that's edited highlights!).

 

[Sirius]

I doubt I’m bringing much insight but in my experience on that route trains tend to remain in the same formation throughout the day.

Milngavie - Edinburgh services form Edinburgh to Helensburgh and vice versa.

It’s possible (I wouldn’t say likely) that there was no member of staff on either portion. I’ve seen ticket examiners join at Bathgate and Airdrie on that route.

 

[gsnedders]

I doubt I’m bringing much insight but in my experience on that route trains tend to remain in the same formation throughout the day.

Milngavie - Edinburgh services form Edinburgh to Helensburgh and vice versa.

It’s possible (I wouldn’t say likely) that there was no member of staff on either portion. I’ve seen ticket examiners join at Bathgate and Airdrie on that route.

The Strathclyde Manning Agreement requires there to be a TE booked for every service, though if they fail to make it (for whatever reason) the train can operate without.

 

[Sirius]

The Strathclyde Manning Agreement requires there to be a TE booked for every service, though if they fail to make it (for whatever reason) the train can operate without.

Does that apply to the entire length of the route? (Genuinely curious)

(Seperately the TE is mentioned as being in the front set on social media).

 

[robbeech]

On some (newer?) units isn't it an automatic process at the time of coupling? The likes of 185's seem to extinguish all "buried" lamps at point of electrical coupling

Likely, but I’m fairly convinced that they don’t automatically come back on when you uncouple. If they do, it’s potentially concerning.

 

[DanDaDriver]

Likely, but I’m fairly convinced that they don’t automatically come back on when you uncouple. If they do, it’s potentially concerning.

I know 222’s automatically extinguish the lamps in the centre and then they come back on to whatever setting they were prior to coupling if the uncouple button is pressed.

 

[theironroad]

If the train, thought, for whatever reason, that it was supposed to be uncoupled then wouldn't the tail lights illuminate automatically?

I can't speak for 334 but on 450/444 desiro stock, yes if it uncoupled correctky, when detachments are made then tail lights will illuminate automatically but frontal lights have to be manually set. When a driver keys off from the front of the train for a detachment to be made in the middle, then both tail and frontal lights will be illuminated until the driver keys back in. There is a taillight override to extinguish them, but not really used as electrically coupling and uncoupling sorts it.

Tbh, I've never worked on semaphore block systems where the signaller is responsible for observing a taillight, I do see in post#1 of this thread the picture of the remaining unit has no tail or frontal lights illuminated though the top left destination indicator has power, so I assume the lighting module does too. Maybe the front portion left with no lights in a similar fashion, but I don't know that.

 

[jagardner1984]

There's a 15 minute service in each direction at Uphall, so has anyone been able to fathom how a train could sit there for 30 minutes and nobody realised?

In addition, there's CCTV on the station monitored from Dunfermline. Should it not have become apparent fairly quickly what had happened?

Is 30 minutes not the time it took passengers to leave the train (by media reports) ?

Presumably as the next station is a few minutes away, the signaller would have been notified by the driver at this point, in addition to whatever errors the signalling system was showing.

If the driver was at the next station was it not a lack of someone suitable to take charge of the stranded train and release the doors that was the issue ? Presumably services in the opposite direction passed in that time.

It sounds like a very regrettable PR incident for Scotrail rather than one in which passengers were placed in real danger. RAIB will doubtless have something preliminary out relatively quickly.

 

[Ben Glasgow]

So I did some investigating and trawled through all the tweets and replies to various tweets to Scotrail or/and passengers tweeting each other when things kicked off.

*Interestingly it turns out that passengers knew something was up when they were stuck at Uphall for far too long, possibly before even the staff in the train that left knew something was amiss.*

Anyways, someone reported that the front 3 carriages lost power (lights off) temporarly whilst the whole train was sitting at Uphall before departing and leaving the 3 carriages at Uphall. Anyone want to take a stab as to what happened? This sounds like a key moment when something went wrong or was in the process of going wrong.

I have literally zero knowledge of the software and hardware intergration between all the systems but could something have tripped causing the uncoupling? Or do you reckon the loss of power in the portion of the train that left the station was a direct effect from unexpected decoupling?