Northern rolling stock changes post electrification

[AM9]

My local line goes through a forest and yesterday services were operated by a mix of 142s, 150s and 156s. There were some minor delays due to leaf fall problems but the only significant one was a service delayed by a signal problem. It seems the Chat Moss line with 319s and less trees faired badly in comparison.

But all the NW lines over which 319s operate don't seem to have an excessive amount of tree cover. I noticed that tracks tend generally to have wider margins up there than is normal for main routes down here, maybe because land itself is cheaper so it has survived the BR/Railtrack/National Rail stampede to sell every square metre outside the structure gauge that shrunk the SE routes' geographical footprints.

 

[northwichcat]

But all the NW lines over which 319s operate don't seem to have an excessive amount of tree cover.

Exactly. Chat Moss shouldn't be affected that much by leaf fall problems but yesterday Liverpool to Wigan seemed to be the only route Northern were warning of significant problems due to leaf fall.

 

[LNW-GW Joint]

Exactly. Chat Moss shouldn't be affected that much by leaf fall problems but yesterday Liverpool to Wigan seemed to be the only route Northern were warning of significant problems due to leaf fall.

And yet there was extensive de-greening of the route over the past couple of years for the electrification project, especially in Olive Mount cutting and around Garswood on the Wigan line.
319s do slip very easily on damp rail though, irrespective of leaf fall.
Places like Edge Hill (emerging from the Lime St tunnel/cutting) and around Eccles seem particularly prone - ie when accelerating hard up to line speed.
On winter conditions, Liverpool and Wirral are mild by northern standards and particularly don't get as much frost and snow as places further inland.
Allerton is quite a good place to keep them out of the worst conditions.

 

[driver_m]

Degreening an area doesn't always totally work. An example of this is Bangor on the North Wales coast. Network Rail have been brutal in sections around there and yet the it is still very slippy this week. The chat moss is still quite overgrown and very green in sections so I'm not surprised they are struggling at the moment.
--- old post above --- --- new post below ---
Sure I've just seen 2 sets at Wolverton in the departure road

 

[gab]

Another 319 fromWolverton to Allerton tonight.
Anyone know which one?

 

[geoffk]

Can only be 366 or 379!

 

[Brian Aylott]

Can only be 366 or 379!

Or both
Brian

 

[PHILIPE]

Or both
Brian

Yes. It was both of them.

 

[DJH1971]

Could well need some more when Manchester to Preston and Preston and Blackpool is wired.

 

[deltic08]

My local line goes through a forest and yesterday services were operated by a mix of 142s, 150s and 156s. There were some minor delays due to leaf fall problems but the only significant one was a service delayed by a signal problem. It seems the Chat Moss line with 319s and less trees faired badly in comparison.

Every coach on a 142, 150, 156 is a motor coach even if only two axles are driving. The motor coach on a 319 is moving three additional coaches.

Two 142 units (four coaches) have eight driving axles whereas a four coach 319 unit only has four driving axles or half the contact footprint with the railhead. Considering contact with the rail is the area of a £2 coin on each wheel, no wonder 319s slip on a greasy rail accelerating.150/156 units have the same number of driving axles per coach as a Pacer.

Stopping is another matter with a 319 having 32 braked wheels whereas a twin unit 142 has only 16 so half the contact area with rail to stop. 150/156 units have the same braking capability of 319s.

 

[childwallblues]

Yes. It was both of them.

That makes the full quota of 20.

 

[AM9]

Every coach on a 142, 150, 156 is a motor coach even if only two axles are driving. The motor coach on a 319 is moving three additional coaches.

Two 142 units (four coaches) have eight driving axles whereas a four coach 319 unit only has four driving axles or half the contact footprint with the railhead. Considering contact with the rail is the area of a £2 coin on each wheel, no wonder 319s slip on a greasy rail accelerating.150/156 units have the same number of driving axles per coach as a Pacer.

Stopping is another matter with a 319 having 32 braked wheels whereas a twin unit 142 has only 16 so half the contact area with rail to stop. 150/156 units have the same braking capability of 319s.

It's not the ratio of driven to trailing wheels that matters but the ratio of adhesive weight to trailed weight. Thus the MSO on the 319s is heavier than the other three cars so the adhesive weight is more than 50%. Similarly, the distribution of weight over the axles of DMU vehicles determines the adhesive weight. It may not be significantly higher over the driven bogie/axle, particularly on shorter vehicles such as class 142s.
As far as contact area goes, it doesn't make that much difference, in fact under low grip conditions, the higher the contact pressure the better to displace railhead contamination. Indeed, at loads nearer the maximum per axle, 25t?, there is a small but measurable limited degree of temporary material deformation at the point of contact caused by the high pressure.This is similar to pneumatic tyres, where cars with narrow tyres perform better in snow conditions than those with wide treads, (all other things being equal).

 

[edwin_m]

It's not the ratio of driven to trailing wheels that matters but the ratio of adhesive weight to trailed weight. Thus the MSO on the 319s is heavier than the other three cars so the adhesive weight is more than 50%. Similarly, the distribution of weight over the axles of DMU vehicles determines the adhesive weight. It may not be significantly higher over the driven bogie/axle, particularly on shorter vehicles such as class 142s.
As far as contact area goes, it doesn't make that much difference, in fact under low grip conditions, the higher the contact pressure the better to displace railhead contamination. Indeed, at loads nearer the maximum per axle, 25t?, there is a small but measurable limited degree of temporary material deformation at the point of contact caused by the high pressure.This is similar to pneumatic tyres, where cars with narrow tyres perform better in snow conditions than those with wide treads, (all other things being equal).

Indeed so, although the motor coach of the 319 etc would have to be the weight of the three trailers combined if it was to reach 50% adhesive weight. I haven't checked but I'm pretty sure this isn't so.

The weight distribution within a vehicle is going to be pretty close to 50% on each bogie otherwise the dynamics would get very odd indeed.

 

[AM9]

Indeed so, although the motor coach of the 319 etc would have to be the weight of the three trailers combined if it was to reach 50% adhesive weight. I haven't checked but I'm pretty sure this isn't so.

The weight distribution within a vehicle is going to be pretty close to 50% on each bogie otherwise the dynamics would get very odd indeed.

Yes my mistake, - don't know why I said 50%, on a 319 it is probably above 25% though.

 

[ed1971]

Hi,

I noticed today at Wigan North Western that the 18:50 to Preston was formed with a 142 and the 18:51 to Liverpool LS a 156, when 319s would usually be diagrammed.

Would this be due to the wheel slip problems on 319s owing to the leaf fall season?

Earlier today I travelled on a 323 and this too had wheelslip to some extent.

 

[317 forever]

This initial batch is 20 units. There could be more to follow if the plans to cascade the 323s to the West Midlands reach fruition.

 

[DJH1971]

Hi,

I noticed today at Wigan North Western that the 18:50 to Preston was formed with a 142 and the 18:51 to Liverpool LS a 156, when 319s would usually be diagrammed.

Would this be due to the wheel slip problems on 319s owing to the leaf fall season?

Earlier today I travelled on a 323 and this too had wheelslip to some extent.

The 319's don't seem to like wet weather too.

 

[Loop & Link]

That 1850 comes from Blackpool and as Blackpool isn't electrified it has to be a DMU.....

 

[Xenophon PCDGS]

Earlier today I travelled on a 323 and this too had wheelslip to some extent.

Since the idea seems to divest Northern Rail of its Class 323 units eventually, how well do these seem to fare regarding wheelslip in leaf-fall season in comparison to the Class 319 units?

 

[AM9]

Since the idea seems to divest Northern Rail of its Class 323 units eventually, how well do these seem to fare regarding wheelslip in leaf-fall season in comparison to the Class 319 units?

It's difficult to say precisely as they don't travel on the same routes. Down south on their native routes, the 319s do clearly have more problems than the Electrostars but then so do 455s struggle compared with Electrostars and Desiros, also 321s don't perform any better when compared to 360s.
The problem is only really there for about 4 weeks per year and at least Network Rail are now managing lineside leaf-fall potential a lot better than in the '80s and '90s when those who lived next to lines regarded their right to maximum tree cover on NR (then BR) land as overriding the need to run rail services safely.

 

[Camden]

The 323s don't seem to do very well, for many years London Midland/Centro have an autumn leaf fall timetable on the cross city line which is a shadow of its summery self.

 

[northwichcat]

Hi,

I noticed today at Wigan North Western that the 18:50 to Preston was formed with a 142 and the 18:51 to Liverpool LS a 156, when 319s would usually be diagrammed.

Would this be due to the wheel slip problems on 319s owing to the leaf fall season?

Earlier today I travelled on a 323 and this too had wheelslip to some extent.

It's unlikely that Northern would have changed the booked traction due to leaf fall issues, it's more likely that there was a train faults with a 319 or even a shortage of available crews who sign 319s.

 

[Loop & Link]

As I said above its booked a DMU because it comes from Blackpool.

To be fair there haven't been many DMU substitutions vice 319's, the 319's have all been sticking to their booked work, despite one or two failures.

And the unit that failed due to the struggling to get traction at Thatto Heath the other week was down to a sander issue.

 

[northwichcat]

As I said above its booked a DMU because it comes from Blackpool.

ed1971 mention 2 services not being operated by 319s:
18:03 Blackpool North to Liverpool Lime Street (18:50 from Wigan)
18:00 Liverpool Lime Street to Preston (18:51 from Wigan)

Obviously the first one is usually not a 319 due to starting from Blackpool as you said but you didn't say the second is usually not a 319.

On Friday the Blackpool-Preston section of the 18:03 Blackpool North to Liverpool Lime Street was cancelled. It looks like there was no conductor available and the unit ran ECS to Preston and then did Preston to Liverpool in passenger service, so it may have appeared on CIS and in NRE as an arrival from Preston.

 

[Class377/5]

It's difficult to say precisely as they don't travel on the same routes. Down south on their native routes, the 319s do clearly have more problems than the Electrostars but then so do 455s struggle compared with Electrostars and Desiros, also 321s don't perform any better when compared to 360s.
The problem is only really there for about 4 weeks per year and at least Network Rail are now managing lineside leaf-fall potential a lot better than in the '80s and '90s when those who lived next to lines regarded their right to maximum tree cover on NR (then BR) land as overriding the need to run rail services safely.

319/455 have single motor coach. Electrostars have three. This is why the Electrostars cope better add they have more places to put the effort where as the BR designed units have all power in one place making them more likely to suffer when conditions are great. (And I've bad mouth BR so I'm sure someone will have a pop at me for that shortly).

 

[Loop & Link]

ed1971 mention 2 services not being operated by 319s:
18:03 Blackpool North to Liverpool Lime Street (18:50 from Wigan)
18:00 Liverpool Lime Street to Preston (18:51 from Wigan)

Obviously the first one is usually not a 319 due to starting from Blackpool as you said but you didn't say the second is usually not a 319.

On Friday the Blackpool-Preston section of the 18:03 Blackpool North to Liverpool Lime Street was cancelled. It looks like there was no conductor available and the unit ran ECS to Preston and then did Preston to Liverpool in passenger service, so it may have appeared on CIS and in NRE as an arrival from Preston.

Sorry, communication error on my part.

1800 to Preston (1851 ex-Wigan) is booked a 142 on Saturday's. It's a Blackpool driver that works it, who aren't currently competent on 319's as I understand it. Conductors at Blackpool are competent 319's.

So what ed1971 saw is correct and booked to happen, no shortages or issues with 319's.

 

[DY444]

319/455 have single motor coach. Electrostars have three. This is why the Electrostars cope better add they have more places to put the effort where as the BR designed units have all power in one place making them more likely to suffer when conditions are great. (And I've bad mouth BR so I'm sure someone will have a pop at me for that shortly).

And Electrostars and other modern emus have the major advantage of having 3 phase ac motors. These react much better than dc motors when wheel slip occurs.

 

[Class 170101]

The major problem with low temperature is icing on 3rd rail track (which of course won't trouble OLE in the North-west).

There can be issues with ice on the OLE

Have any Class 319s been seen to do a lot of excessive sparking yet?

EDIT You Tube video of sparking (albeit Class 333 units)
https://www.youtube.com/watch?v=cACEklXINdQ

 

[WatcherZero]

We do suffer from black ice on overheads up here. If its below freezing the snow/hail doesn't stick to the overheads, however if its above freezing, rains, then the temperature drops and particularly if it keeps fluctuating above and below zero then layers of ice do build up.

That said we haven't yet had particularly cold snaps this year, a couple of one off frosts before the wet weather.

 

[Nym]

And Electrostars and other modern emus have the major advantage of having 3 phase ac motors. These react much better than dc motors when wheel slip occurs.

Really, so by that logic the S Stock with all axles motored with 3 phase motors would have very little chance at all of slipping...

Ride one round Moor Park and Rickmansworth and you'll know that's not true..