Thameslink core - broken down train (24/3)

[John1975]

No DC extensions allowed these days.
Far better to extend the ac to Blackfriars (through platforms only). That would benefit the supply to trains climbing from city station and as a bonus, prevent the recurrence of a pantograph not dropping when transferring to DC and damaging the roof.

But would do nothing to address the undesirable and all too frequent power changeover problems which already has the potential to wreak carnage let alone when they try and squeeze 24tph through the core, particularly as the increased use of 12 cars has rendered the standard Smithfield bolthole all but useless.

 

[AM9]

Okay, so control access to the platform. That may be easy enough at St. Pancras, but not so easy at Farringdon where there are multiple entrances. Furthermore, if you start controlling access to the southbound Thameslink platform, you've now created a problem on the adjacent Met platform. The people still have to go somewhere, they don't just disappear into thin air! And whilst this is going on, more trainloads are arriving every couple of minutes on the interchanging lines.




Yet the incident still happened. As I said before, with the member of staff standing just metres away, and unaware of the unfolding incident until it was too late. The incident was only picked up because the driver happened to observe something of concern on his in-cab monitor after the train had started moving. How will your whizzo dispatch staff stop a train if something happens at this point? LU's monitors continue broadcasting to the driver until the full length of the train has left the platform of course.




I think you'll find it would need to be a bit more than 30s or 1 minute to be effective. Indeed, you can end up with the entire station in chaos, and possibly the surrounding streets too. Ever used Holborn in the peak hours? And, of course, with many of the Thameslink services being half-hourly, miss the train and it's a half-hour delay. In that situation I'd certainly be making sure I maintain my spot on the platform to ensure I get a seat when the train eventually does arrive.

LU's crowd control is a little different because generally their platforms clear very quickly, mainly because there's less variation between destinations. Only the Northern Line has a divide very close to London, and even then you're still talking about a train every 4-6 minutes to each route. Thameslink is a completely different ball game - at least five different service groups heading north, much less frequent than LU. And many more people travelling further and therefore keen to secure a seat.

The bottom line is that there is no easy fix that can resolve the issue. Drivers just pulling away blind clearly isn't remotely sensible. Only an 'elf 'n safety gone mad' imbecile would see that as the way ahead (sorry about the pun). If the incidence of platform overcrowding became a regular issue, then as I said upthread, the hard nosed business decision would come back into play and other options would become more financially/politically/legally acceptable, e.g.:

temporarily send all fast trains through to STP meaning that after a while, passengers would clear from the overcrowded platform by changing at STP from the slows. There wouldn't be any hanging around then as all trains would stop there.
close the western footbridges and force all passengers wanting to travel on Thameslink (mainly northbound) go via the large Crossrail/Thameslink circulation area
(ultimately), if the problem looks like being a permanent feature of peak travel, address the matter of providing more space on those platforms. Expensive, but the current arrangements for the core are meant to provide for at least 20 years growth. If such an enhancement at Farringdon is necessary then so be it.​

 

[AM9]

But would do nothing to address the undesirable and all too frequent power changeover problems which already has the potential to wreak carnage let alone when they try and squeeze 24tph through the core, particularly as the increased use of 12 cars has rendered the standard Smithfield bolthole all but useless.

Actually, it would help as in extremis, a train that failed to switch from ac to DC could empty its passengers who could tranfer to a DC train in the bay platforms. The train could then either set back down to City using the crossover at the bottom of the incline and clear back through the core, or if it couldn't power up at all, it could be pushed towards Elephant & Castle by a following train where provision could be made to park it on the four-track section.
In the event of a failure to switch from DC to ac, the option to draw it back and park it would then also be an option.
So with failures to switch either way, the core itself could be cleared reasonably quick with no absolute need to drag a train from the depths of CTK or ZFD. An additional benefit would be the fact that movements would be done in the open rather than subsurface. Recovery from the parking location could be by diesel loco if desired.
AC/DC changeover has been a practice in several places for decades, ever since the introduction of the 'PEP' train design followed by the 319s. Just how many instances of changeover failure have there been involving 700s? How many of those have been properly attributed to a train failure, an infrastructure failure or a systematic failure.

 

[Taunton]

The 313s were never entirely reliable with changeovers, I did read that from their early days problems at Drayton Park meant there were special procedures to handle it. Later, when used on the North London line, there was a period when they changed back and forth several times (I think four) in each single journey, as it was converted to 25Kv in sections. Changeover failures became one of the features of the gross unreliability of the line at that time. The radio travel news seemed to regularly announce suspension "due to a broken down train" at one of the changeover stations.

Correct me if I'm wrong, but are there more issues going from AC to DC rather than the other way round?

 

[Busaholic]

Split service usually mean "game over" for the day in terms of through services. One of the biggest issues is the dominance of Bedford train crew depot - right at the far end of the line , so a stranded BF driver south of the block seems (and is) a long way from home.

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This type of equation interests me greatly, because so much can stem from it, and 'accidents of history' can skew things for decades thereafter if not addressed at some stage. So when the Great Northern lines get subsumed into Thameslink will the same apply? i.e. will there be more drivers/trains from Northern depot(s) than from Southern ones on those through services. I'm using Southern and Northern in the geographical sense, by the way. During my brief sojourn with London Underground management, a long while ago, I do remember venting frustration at the positioning of Northern Line depots, not that that made the slightest difference!

 

[Joe Paxton]

This type of equation interests me greatly, because so much can stem from it, and 'accidents of history' can skew things for decades thereafter if not addressed at some stage. So when the Great Northern lines get subsumed into Thameslink will the same apply? i.e. will there be more drivers/trains from Northern depot(s) than from Southern ones on those through services. I'm using Southern and Northern in the geographical sense, by the way. During my brief sojourn with London Underground management, a long while ago, I do remember venting frustration at the positioning of Northern Line depots, not that that made the slightest difference!

I had hoped that with the GTR 'merger' of Thameslink and Southern would come some sort of improved crewing arrangements for drivers on the TL route - i.e. more drivers south of the river who could drive TL trains. (Also, there was quite some turmoil in industrial relations between FCC management and the TL drivers.)

I really want the new Thameslink to work, but this thread isn't terribly encouraging. Five hours to rescue and move a knackered train...

(Perhaps MTR need to win the next franchise that encompasses Thameslink?)

 

[Minstral25]

Exactly the same as LU does, firstly control access to the platform before it gets unsafe, then when it is a potential hazard, provide appropriate dispatching assistance to the driver.

There are major difficulties with this type of crowd control in the core. When you block commuters at the entrance you'll probably force them to miss their train. Their next train is probably 15-30 minutes away so they will fill the platform for that 15-30 minutes meaning the next lot of customers for the trains in-between are stuck in the crowd control and then missing their train in turn creating queues for much longer and successive groups of angry passengers because they missed their trains.

There are a lot of major destinations to the south with 30 minute gaps - Sevenoaks, Maidstone, Greenwich/Rainham, East Grinstead, Wimbledon/Sutton loop etc and a lot of the "15" minute gaps will in reality be "7" minute then "23" minute gaps causing a lot of platform hogging.

 

[Chris M]

I think the only solution to the platform hogging would be to really push the "take the first train and change where necessary" (STP or Blackfriars I guess) model for the core. If you have the space you could I suppose have separate queues per route meaning that you only get released onto the platform when the train going your way is the next one. That way the platforms would almost* completely clear each time.

*there will still be some who pick the queue going first then spend the next 20 minutes waiting on the platform. Without a draconian change in bylaws I'm not sure that you can stop this.

 

[AM9]

There are major difficulties with this type of crowd control in the core. When you block commuters at the entrance you'll probably force them to miss their train. Their next train is probably 15-30 minutes away so they will fill the platform for that 15-30 minutes meaning the next lot of customers for the trains in-between are stuck in the crowd control and then missing their train in turn creating queues for much longer and successive groups of angry passengers because they missed their trains.

There are a lot of major destinations to the south with 30 minute gaps - Sevenoaks, Maidstone, Greenwich/Rainham, East Grinstead, Wimbledon/Sutton loop etc and a lot of the "15" minute gaps will in reality be "7" minute then "23" minute gaps causing a lot of platform hogging.

AQlthough such a situation may cause some passengers to mis a 2tph service, we are talking about events that generally happen quite infrequently, (I wish we had verified data confirming the number of class 700s that have actually failed and caused severe delays, because that would make the discussion less skewed by all failures within a mile of a class 700 being attributed to that class of train).
However, whatever the temporary delay caused by passenger crowding management, that pales into insignificance when the disruption caused by the alternative 'just steam on regardless' solution where an injury or worse occurs. There are of course a few posters on here who still complain about the inconvenience they personally suffer by a selfish suicide action when it is on their route.

 

[bramling]

AQlthough such a situation may cause some passengers to mis a 2tph service, we are talking about events that generally happen quite infrequently, (I wish we had verified data confirming the number of class 700s that have actually failed and caused severe delays, because that would make the discussion less skewed by all failures within a mile of a class 700 being attributed to that class of train).
However, whatever the temporary delay caused by passenger crowding management, that pales into insignificance when the disruption caused by the alternative 'just steam on regardless' solution where an injury or worse occurs. There are of course a few posters on here who still complain about the inconvenience they personally suffer by a selfish suicide action when it is on their route.

The chances of disruption are rather increased on Thameslink simply due to the increase of route mileage. It's not just about the 700s, which hopefully will improve their reliability as teething issues are ironed out, but the infrastructure, plus everything else. Under Thameslink a suicide on the Southern Region will affect routes north of the river, which hitherto would not have been the case.

As you say, "let's steam on regardless" certainly isn't the way to go - but having to have frequent crowd control isn't ideal either. Watch out for Finsbury Park too if the core goes down for any reason, although of course this has been dismissed as fantasy by a certain "dearly-departed" poster.