Disruption to Southeastern services from Victoria (23/11)

[sprunt]

There is major disruption expected until 20.00. The NRE page for it says:

The 09:42 London Victoria - Dover service broke down just outside of London Victoria this morning. The reason that the train broke down is because it became 'gapped'. This meant that the train was stuck over part of the track which does not have a power supply. The part of the train that draws power from the electric rails is over that gap. This train has now moved back into London Victoria.

However, in addition to the above incident, the 11:20 Gravesend to London Victoria also became gapped on the way in to London. This train is now also in London Victoria so all lines are open to and from the station again, but with severe disruption expected to continue while we work to get trains back on time.

I'm sure this is just something beyond my knowledge, but if one train can get stuck over a section of track with no power supply, why doesn't it happen more. Without speculation on the exact cause of what's happened here, can anyone explain this in a bit more detail? What might cause it to happen as a one-off rather than for every train that goes over that bit of track? Is it just likely to be a freak bit of bad luck with the train happening to be stopped with the pick-up over that precise bit of track?

 

[BluePenguin]

It is very unlucky for this to happen twice in one day isn't it?

 

[Robsignals]

Must be a bit more wrong, gapping involves the shoe at each end of the unit being over 2 gaps which is unlikely. Perhaps one shoe was damaged or had lost the carbon block due to arcing on some icy conductor rail in the last few days. Also requires the train to be running very slowly or stopped in the wrong place maybe a passenger alarm operated. Drivers should be aware of high risk locations ie complex point work and maintain speed.

 

[30907]

The good news is that no-one tried to self-evacuate, apparently, unlike a month ago when something rather similar happened.

https://www.railforums.co.uk/thread...ails-yards-from-victoria.172261/#post-3689061

The second incident appears to have been at a different location.

 

[TRAX]

It seems odd to me that a train could have all of its shoes hanging, even on the shortest of sets. How many shoes does a 3-car 375 have on each side ? I know these certainly weren’t 3-car trains, they would’ve been longer, which would narrow the chances of this happening even more.

 

[Surreytraveller]

It's quite possible for all the shoes on one side to be knocked off if the train had passed a dodgy piece of conductor rail somewhere

 

[Larry Trapp]

It's quite possible for all the shoes on one side to be knocked off if the train had passed a dodgy piece of conductor rail somewhere

Does it display in the what side the shoes are working on these units or just a line light ?

Sorry if I didn’t word it very well but I wondered if it could have happened elsewhere and only become a problem in the locations the incidents happened?

 

[bionic]

Victoria is rife for gapping. Happens from time to time at Cannon Street too. Leaving on a single yellow and stopping at the next one would easily do it. Although usually you'd get out on more than that.

 

[fusionblue]

Can someone explain how a Thameslink 700 to Orpington (going through the core) was cancelled because of this?

 

[tsr]

Can someone explain how a Thameslink 700 to Orpington (going through the core) was cancelled because of this?

Southeastern drivers cross-cover for various GTR services an awful lot (though perhaps a little less now than pre-May), so it could be a resourcing issue as a result of SE crew displacement... or alternatively it could be the driver was delayed en-route to work or between parts of their duty due to the gapped trains.

 

[ComUtoR]

Must be a bit more wrong, gapping involves the shoe at each end of the unit being over 2 gaps which is unlikely.

The same word being used to describe different meanings.

In the railway sense a unit 'gaps' where there are no shoes in contact with the running rail. This is exactly as you describe where the shoes are in a gap in the rail. For a unit to be 'gapped' this means all shoes so where a unit may have multiple shoes each are in multiple gaps. Units 'gap' all the time. There are loads of them.

 

[TRAX]

It's quite possible for all the shoes on one side to be knocked off if the train had passed a dodgy piece of conductor rail somewhere

In which case it would’ve affected more than two trains, or if the issue was detected after the first stranded train it wouldn’t’ve affected a second one much later ?

 

[GW43125]

It seems odd to me that a train could have all of its shoes hanging, even on the shortest of sets. How many shoes does a 3-car 375 have on each side ? I know these certainly weren’t 3-car trains, they would’ve been longer, which would narrow the chances of this happening even more.

The first train to gap was formed of a 4 car 465 & 2 car 466 so it’s entirely possible that, say, the front shoe on the 465 was defective then the other three shoes (465& both on a 466) stopped in a big gap. We used to have a similar issue at Waterloo and there was an instruction that if you were formed TC-TC-REP (with the REP at the back), you didn’t take a yellow signal out of Waterloo. Ever.