Porterbrook Cl.769 'Flex' trains from 319s, initially for Northern

[Energy]

My understanding, from reading "in the know" contributions on another thread, is that 769s can switch from diesel to electric on the move. GWR have a requirement for this on the North Downs Line at Aldershot South junction.

That bit is third rail. Assuming the diesel engines are using the same 750v DC bus as the 3rd rail shoes then a changeover while moving would be possible.

 

[td97]

Salford Crescent is bi-directional. What happens if the 769 in electric mode is routed into the up platform when heading in the down direction towards Atherton?

Then the signaller has set a wrong route, which the driver has accepted. P1 does not have access to the down Atherton line.

It is not.

Thanks for clarifying. Seems to be a different policy to 80x changeover

 

[TurboMan]

My understanding, from reading "in the know" contributions on another thread, is that 769s can switch from diesel to electric on the move. GWR have a requirement for this on the North Downs Line at Aldershot South junction.

Diesel to DC, yes. DC to AC, no.

 

[D365]

Diesel to DC, yes. DC to AC, no.

Thanks for clarifying. That confirms it’s a feature that is specific to the 769/9.

 

[TurboMan]

Thanks for clarifying. That confirms it’s a feature that is specific to the 769/9.

I meant to type: Diesel to DC, yes, Diesel to AC no. The basic principle is that switching to AC is not possible on the move (at least according to Porterbrook). Switching between modes dynamically otherwise is possible (i.e. from AC to DC/diesel, and from DC to diesel and vice versa). That applies to any 769, as it derives from 319 functionality. However, what is technically possible is not necessarily desirable from an operational point of view, so there may be operational restrictions on changeover procedures.

 

[Bovverboy]

And why is this?

The 0636 Victoria to Southport is routed via Atherton, but diagrammed for a 769. It would hardly be worthwhile to pan up just for Victoria to Salford Crescent. I don't know what is meant by traction performance issues.

 

[175001]

It's a company instruction.

 

[Bovverboy]

It's a company instruction.

So does 'traction performance issues' mean the same as 'company instruction'?

 

[WAO]

I imagine that both mean that there's a non-zero risk of a unit "sit down" when a change-over ac-diesel is attempted. Everyone would be happier if 769's just purred contently to and from Southport, (without the panto-mime!).

WAO

 

[AM9]

I imagine that both mean that there's a non-zero risk of a unit "sit down" when a change-over ac-diesel is attempted. Everyone would be happier if 769's just purred contently to and from Southport, (without the panto-mime!).

WAO

Apart from those who inhale too much diesel pollution already.

 

[507020]

I imagine that both mean that there's a non-zero risk of a unit "sit down" when a change-over ac-diesel is attempted. Everyone would be happier if 769's just purred contently to and from Southport, (without the panto-mime!).

WAO

I’m assuming the issue is that when the engine has been sat cold all night in the siding, it’s better to attempt to start it from there and run from the station all the way to Southport via Atherton and back to Bolton on Diesel rather than let the unit get to Salford Crescent on AC only to block the line just in time for the morning peak, but there must be a more reasonable way to operate them than that.

 

[WAO]

A well filled DEMU is a lot cleaner net than having the same passengers in cars!

WAO

 

[Bald Rick]

A well filled DEMU is a lot cleaner net than having the same passengers in cars!

WAO

It’s rather closer than you might think, given the current declining average carbon emissions from cars.

 

[AM9]

A well filled DEMU is a lot cleaner net than having the same passengers in cars!

WAO

I wasn't comparing it to a road vehicle. A class 769 train in diesel mode is a lot dirtier than the same train in electric mode.

 

[507020]

I wasn't comparing it to a road vehicle. A class 769 train in diesel mode is a lot dirtier than the same train in electric mode.

How much cleaner is a 769 DEMU from the Victoria reversing siding into the station and back to Southport via Atherton on Diesel than a pair of Sprinters with 30 year old engines coming ECS from Newton Heath which would otherwise make the journey on the unelectrified line?

 

[Wyrleybart]

I’m assuming the issue is that when the engine has been sat cold all night in the siding, it’s better to attempt to start it from there and run from the station all the way to Southport via Atherton and back to Bolton on Diesel rather than let the unit get to Salford Crescent on AC only to block the line just in time for the morning peak, but there must be a more reasonable way to operate them than that.

But that is not what railways is about. You build trains that work.
I recall back in the early oughties when XC were running it's last 86s and 47s, a new Bombardier engineer asking what used to happen when one of the old trains "lost an engine". Well it obviously sat down and stopped the job, but it wasn't bloody designed to do that !!! AC locos are designed to run at least 100 hours in traffic between exams and very largely did that. The only bimodes we had back then were the 40 odd class 73s on the Southern region, and even they were very reliable so long as they didn't get too warm.

Trains should be built to work, and 769s are just too frail.

 

[37201xoIM]

But that is not what railways is about. You build trains that work.
I recall back in the early oughties when XC were running its last 86s and 47s, a new Bombardier engineer asking what used to happen when one of the old trains "lost an engine". Well it obviously sat down and stopped the job, but it wasn't bloody designed to do that !!! AC locos are designed to run at least 100 hours in traffic between exams and very largely did that. The only bimodes we had back then were the 40 odd class 73s on the Southern region, and even they were very reliable so long as they didn't get too warm.

Trains should be built to work, and 769s are just too frail.

Jaded and fatuous Old Railway thinking....

Anyway, Uncle Roger needs something to be the trusty stalwart at the bottom of the MTIN table every month, doesn't he, ergo 769s play a valuable role...

 

[D365]

Trains should be built to work, and 769s are just too frail.

Nobody builds them to not work… but the state of the 319s post-Thameslink was not at all anticipated.

 

[AM9]

How much cleaner is a 769 DEMU from the Victoria reversing siding into the station and back to Southport via Atherton on Diesel than a pair of Sprinters with 30 year old engines coming ECS from Newton Heath which would otherwise make the journey on the unelectrified line?

A single class 769 with it's two nearly new (ISTR) Euro IIIb engines meeting the demands of two matched generators is probably not only cleaner than a pair of 35-38 year old class 150s thrashing into torque converters to get started, but also a lot more fuel efficient. And that is when the 769 is working in diesel mode. Of course there's no competition between the two whenthe 769 is running under wires with zero co2 or particulates from the engines whilst the 150s continue to do their thing everywhere they go.

 

[175001]

So does 'traction performance issues' mean the same as 'company instruction'?

As someone who drives them, yes.

 

[Dspatula]

A single class 769 with it's two nearly new (ISTR) Euro IIIb engines meeting the demands of two matched generators is probably not only cleaner than a pair of 35-38 year old class 150s thrashing into torque converters to get started, but also a lot more fuel efficient. And that is when the 769 is working in diesel mode. Of course there's no competition between the two whenthe 769 is running under wires with zero co2 or particulates from the engines whilst the 150s continue to do their thing everywhere they go.

You missed it's cleanness option, to simple sit dead in Southport, Springs Branch, etc. Truly the green train of the future...

 

[AM9]

You missed it's cleanness option, to simple sit dead in Southport, Springs Branch, etc. Truly the green train of the future...

I wasn't joking, - everything I have posted on this sub-topic is straight.

 

[507020]

But that is not what railways is about. You build trains that work.
I recall back in the early oughties when XC were running it's last 86s and 47s, a new Bombardier engineer asking what used to happen when one of the old trains "lost an engine". Well it obviously sat down and stopped the job, but it wasn't bloody designed to do that !!! AC locos are designed to run at least 100 hours in traffic between exams and very largely did that. The only bimodes we had back then were the 40 odd class 73s on the Southern region, and even they were very reliable so long as they didn't get too warm.

Trains should be built to work, and 769s are just too frail.

So are Voyagers by the sound of it. Why all modern equipment is of such poor quality in comparison is beyond me, unless it is the case that money has been haemorrhaged at every possible opportunity in the intervening years.

Nobody builds them to not work… but the state of the 319s post-Thameslink was not at all anticipated.

Why on earth would they have been withdrawn early only to be replaced by a stop-gap of Electrostars while they waited for the new Class 700 fleet to be delivered if there was nothing wrong with them?

A single class 769 with it's two nearly new (ISTR) Euro IIIb engines meeting the demands of two matched generators is probably not only cleaner than a pair of 35-38 year old class 150s thrashing into torque converters to get started, but also a lot more fuel efficient. And that is when the 769 is working in diesel mode. Of course there's no competition between the two whenthe 769 is running under wires with zero co2 or particulates from the engines whilst the 150s continue to do their thing everywhere they go.

And this is probably the single reason why they are allowed not to work, although the timetabled services are unacceptable, since quite often 150s and 156s end up working on the original electrified WCML to Alderley Edge, which had EMUs in 1960.

 

[Bald Rick]

Why on earth would they have been withdrawn early only to be replaced by a stop-gap of Electrostars while they waited for the new Class 700 fleet to be delivered if there was nothing wrong with them?

They weren’t withdrawn to be replaced by the electrostars on Thameslink - the electrostars were bought to enable more through Thameslink services and more longer trains as part of the first phases of the Thameslink programme. All the 319s stayed in Thameslink service.

 

[Dspatula]

I wasn't joking, - everything I have posted on this sub-topic is straight.

Never claimed you were.
However if the 769 can't perform its role adequately as a train, then its green credentials are of little consequence.

 

[_toommm_]

A Northern 769 broke down tonight, ironically just outside Newton Heath. Had to be rescued by another 769, blocking the route towards Rochdale for about two hours:

Realtime Trains | 2W83 1917 Southport to Manchester Victoria | 03/09/2022

Real-time train running information for 2W83 1917 departure from Southport to Manchester Victoria on 03/09/2022. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

 

[507020]

A Northern 769 broke down tonight, ironically just outside Newton Heath. Had to be rescued by another 769, blocking the route towards Rochdale for about two hours:

The 769 looks to have been sat there over 2 hours, but I can’t see any disruption caused by the line being blocked though. A 769 failed to call at Clifton on Friday, causing many delays propagating towards Chorley onto the WCML, with a TPE service arriving at Bolton at the same time as a Blackpool North which had stops at Blackrod and Adlington, but being signalled behind it all the way to Leyland…

 

[_toommm_]

The 769 looks to have been sat there over 2 hours, but I can’t see any disruption caused by the line being blocked though. A 769 failed to call at Clifton on Friday, causing many delays propagating towards Chorley onto the WCML, with a TPE service arriving at Bolton at the same time as a Blackpool North which had stops at Blackrod and Adlington, but being signalled behind it all the way to Leyland…

It initially caused my service to be delayed, but we diverted around it as luckily it was in-between signals so it meant we could go via the loop at Brewery Junction.

 

[Geeves]

Thankfully of all the places a 769 could breakdown that was probably the best of the bunch. There was some disruption around 2200 as the line was blocked for thankfully only around 20 mins. The rescue 769 came back and formed the 2320 to Wigan.

 

[_toommm_]

Thankfully of all the places a 769 could breakdown that was probably the best of the bunch. There was some disruption around 2200 as the line was blocked for thankfully only around 20 mins. The rescue 769 came back and formed the 2320 to Wigan.

Yeah, I was on the 21:56 to Leeds which was initially delayed around twenty minutes IIRC.