Divided train at Harlow (30/05)

[Sleepy]

Surprised no-one else has mentioned this today - 2H21 GA 0942 Cambridge North to Liverpool St. formed of 2 x 4 car class 379 reportedly divided while between Harlow Mill and Harlow Town, handful of pax detrained safely. Any history of this type of problem with 379's and what is line speed in this location ?

 

[Desiro360]

Surprised no-one else has mentioned this today - 2H21 GA 0942 Cambridge North to Liverpool St. formed of 2 x 4 car class 379 reportedly divided while between Harlow Mill and Harlow Town, handful of pax detrained safely. Any history of this type of problem with 379's and what is line speed in this location ?

Scary stuff. Glad to hear that no one was hurt in this incident. I am not aware of any incidents like this involving Class 379's before.

 

[357]

Other TOCs with similar designs of Electrostars have been told to close and lock the gangways between units, but can still run them in multiple.

 

[delt1c]

Other TOCs with similar designs of Electrostars have been told to close and lock the gangways between units, but can still run them in multiple.

If there is a known problem it should be rectified,locking the gangways between units minimises the chance on injuries in such an event but surely a fix should be implemented. These are DOO trains so no member of staff on the rear unit to assist passengers

 

[aleggatta]

As part of the investigation, there would be standard checks on the coupler. Part of this is a check to see how much movement there is in the main bearing of the dellner coupler. This was a standard check as part of the major 'M' exams at the toc I worked at, and after the data recorders have been checked for the time of coupling would be the initial point of investigation.

Out of curiosity, is a pull away test part of the coupling process at GA? I know it is down south but IIRC isn't featured in the dellner coupling procedure and was carried over from tightlock days.

 

[Wyrleybart]

Not heard of it with 379s but I was on a train which divided three times on a Rugeley - Birmingham service. I got in the 153 which was trailing a 2 car 170 at Landywood. Things went well until Pleck Jn when the brakes went in as were going through the Slow to Fast crossover. The driver obviously knew what had happened so got the 170 onto the Up Main then walked back to drive us back onto it, then we continued until the same thing happened at the top of Soho bank. After some more walking he coupled us together and we proceeded. Just popping out of Monument Lane tunnel it happened again, so he took the 170 down the platform, then walked back again to fetch us.

bit of a shambles really

 

[rebmcr]

Other TOCs with similar designs of Electrostars have been told to close and lock the gangways between units, but can still run them in multiple.

If there is a known problem it should be rectified,locking the gangways between units minimises the chance on injuries in such an event but surely a fix should be implemented. These are DOO trains so no member of staff on the rear unit to assist passengers

There's nothing to indicate that's the final remedial action.

 

[rebmcr]

As part of the investigation, there would be standard checks on the coupler. Part of this is a check to see how much movement there is in the main bearing of the dellner coupler. This was a standard check as part of the major 'M' exams at the toc I worked at, and after the data recorders have been checked for the time of coupling would be the initial point of investigation.

Out of curiosity, is a pull away test part of the coupling process at GA? I know it is down south but IIRC isn't featured in the dellner coupling procedure and was carried over from tightlock days.

Great Northern do pull-away tests on their Dellner-equipped 387s.

 

[Fincra5]

Other TOCs with similar designs of Electrostars have been told to close and lock the gangways between units, but can still run them in multiple.

I don't think thats accurate. No SN/ GX or GWR (last time I was on one) has such a restriction. GN don't open there's as platform staff at Cambridge (GA) don't get involved in any physical side of split/ attach (which involves transforming the cab).

Surely, if the dellner failed, the Brake Continuity would also fail, resulting in a brake application in both sections. So the risk isn't massive.

 

[plugwash]

The worry is presumably what would happen if someone were standing in the gangway at the time of the split, closing off the gangway until the incident is investigated and remedial action can be taken would mitigate that.

 

[XC90]

What was the outcome after 2 x 334s separated at Uphall in Scotland a year or so ago?

 

[PG]

The worry is presumably what would happen if someone were standing in the gangway at the time of the split, closing off the gangway until the incident is investigated and remedial action can be taken would mitigate that.

I suspect this one will interest the RAIB and so they'll likely have a news story on their website within the next 2-3 weeks.

Until such time as investigations (internal TOC) are concluded then closing the gangway doors seems like a suitable mitigation against the consequences of an unplanned split occurring.

Surely, if the dellner failed, the Brake Continuity would also fail, resulting in a brake application in both sections. So the risk isn't massive.

While I agree that both sections should get a brake application in this situation, I wouldn't like to be crossing the gangway as the rear unit might have slightly better retardation than the front unit!

 

[PG]

What was the outcome after 2 x 334s separated at Uphall in Scotland a year or so ago?

I'm unaware of the RAIB reporting on that incident but it does have its own thread on the forum.
https://www.railforums.co.uk/threads/scotrail-334-becomes-uncoupled-near-uphall-26-11.174134/

 

[Andy Pacer]

Not heard of it with 379s but I was on a train which divided three times on a Rugeley - Birmingham service. I got in the 153 which was trailing a 2 car 170 at Landywood. Things went well until Pleck Jn when the brakes went in as were going through the Slow to Fast crossover. The driver obviously knew what had happened so got the 170 onto the Up Main then walked back to drive us back onto it, then we continued until the same thing happened at the top of Soho bank. After some more walking he coupled us together and we proceeded. Just popping out of Monument Lane tunnel it happened again, so he took the 170 down the platform, then walked back again to fetch us.

bit of a shambles really

That would have been rather unnerving for anyone, but particularly people who dont understand these things.

 

[357]

I don't think thats accurate. No SN/ GX or GWR (last time I was on one) has such a restriction. GN don't open there's as platform staff at Cambridge (GA) don't get involved in any physical side of split/ attach (which involves transforming the cab).

Surely, if the dellner failed, the Brake Continuity would also fail, resulting in a brake application in both sections. So the risk isn't massive.

I can assure you that the instruction has been given soon after this incident happened.

When was the last time you were on one? Was it before this incident?

I would hope that it would stop the train - but I would also hope that the train wouldn't split to begin with! The risk might not be massive, but until the cause is 100% known wouldn't you rather the risk be mitigated ?

 

[Fincra5]

I can assure you that the instruction has been given soon after this incident happened.

When was the last time you were on one? Was it before this incident?

I would hope that it would stop the train - but I would also hope that the train wouldn't split to begin with! The risk might not be massive, but until the cause is 100% known wouldn't you rather the risk be mitigated ?

Like I said, there is no such instruction on Southern or Gatwick Express Electrostars. I can't say for SE or GWR anymore as I haven't been on one for a while (lockdown). I can imagine an instruction is given whilst any issues are checked out. I can come down to the simple things, was a "pull away" test carried out whenever the unit was attached? Couple up too soft and you might a full lock on the Dellner but the electrical circuit might be complete.(etc)

It also wouldn't be at all practical on SN due to all the short platforms Electrostars call at. Currently all the Littlehampton to Victorias (and Vice Versa) call at all stations between Littlehampton and Hove. 4 Stations have 4 Car platforms (for 8-12 car trains) only 4 (5 on the up) actually accomodate 12 coaches...

 

[357]

Like I said, there is no such instruction on Southern or Gatwick Express Electrostars. I can't say for SE or GWR anymore as I haven't been on one for a while (lockdown). I can imagine an instruction is given whilst any issues are checked out. I can come down to the simple things, was a "pull away" test carried out whenever the unit was attached? Couple up too soft and you might a full lock on the Dellner but the electrical circuit might be complete.(etc)

It also wouldn't be at all practical on SN due to all the short platforms Electrostars call at. Currently all the Littlehampton to Victorias (and Vice Versa) call at all stations between Littlehampton and Hove. 4 Stations have 4 Car platforms (for 8-12 car trains) only 4 (5 on the up) actually accomodate 12 coaches...

Ah, understood. No SDO on our network so no issue.

We do a pull away test after coupling on all units, whatever type of coupler they have. Can't speak for other TOCs though. I just always assumed it was a nationwide thing.

 

[JN114]

No such instruction at GWR for 387s either - again wouldn’t be practical with SDO.

 

[Ashley Hill]

If there is a known problem it should be rectified,locking the gangways between units minimises the chance on injuries in such an event but surely a fix should be implemented. These are DOO trains so no member of staff on the rear unit to assist passengers

Another very good reason to have guards on trains!

 

[pompeyfan]

Another very good reason to have guards on trains!

as Much as I agree with you, this isn’t the time or place!

 

[Fincra5]

Ah, understood. No SDO on our network so no issue.

We do a pull away test after coupling on all units, whatever type of coupler they have. Can't speak for other TOCs though. I just always assumed it was a nationwide thing.

AFAIK it is but that doesn't mean a Pull Away test was actually carried out...

 

[pompeyfan]

AFAIK it is but that doesn't mean a Pull Away test was actually carried out...

SWR don’t carry out a pull away test with their Dellner fitted desiros. After the attachment there’s usually a small jolt as the slack is taken up in the coupling.

 

[O L Leigh]

When I signed these units there was a pull test as part of the coupling procedure, so I presume that one was done on this train also. However, even assuming that the unit was only formed up in the sidings at Cambridge and this was it's first trip together in multiple, it still got quite a decent distance before coming apart. But it could have been coupled together for quite a lot longer than this as the modus operandi for these units is to have them in pairs, and I'm not sure to what extent trains are split and reformed at Cambridge. It's certainly not something that seems to happen as a matter of routine. Any train that divides like this will come to a stop automatically and immediately due to the loss of brake continuity.

Linespeed through Harlow is 80mph, but I believe this was a stopping service so probably wouldn't have been going quite that fast.

Not heard of it with 379s but I was on a train which divided three times on a Rugeley - Birmingham service. I got in the 153 which was trailing a 2 car 170 at Landywood. Things went well until Pleck Jn when the brakes went in as were going through the Slow to Fast crossover. The driver obviously knew what had happened so got the 170 onto the Up Main then walked back to drive us back onto it, then we continued until the same thing happened at the top of Soho bank. After some more walking he coupled us together and we proceeded. Just popping out of Monument Lane tunnel it happened again, so he took the 170 down the platform, then walked back again to fetch us.

bit of a shambles really

Not quite the same thing. Cl170s used to suffer from loss of brake continuity due to the connector blocks on the BSI couplers between units pulling apart, but the train itself would not divide. This was particularly the case on tight curves or through pointwork. The only remedy was to unhook and couple up again. It's better now than it was but it's not unheard of for it to happen even now (I've had it three times on ECS moves).

 

[3141]

Another very good reason to have guards on trains!

With an instruction that they should always remain in the rear unit,