125mph non tilt live on WCML

[Tilting007]

To add to this, once the 730's go north of Rugby, they are stopping every 10 or so minutes, so I'd agree with you that there would be very little gain.

Lots to gain if the 75mph sections on the slow lines were increased…

 

[jfollows]

LUMO requires a SoC for MU running. Currently limited to a test SoC and 110mph PS max speed.

SoC please?

 

[hexagon789]

SoC please?

Summary of Compatibility

 

[jfollows]

Summary of Compatibility

Thank you.
I found, albeit possibly garbled by AI at https://www.google.com/search?client=firefox-b-m&q=network rail summary of compatibility

A Network Rail Summary of Compatibility (NRSC) is a document required under
RIS-8270-RST to confirm that new, modified, or cascaded rolling stock is technically compatible with specific infrastructure, such as gauging, power systems, and signalling. It acts as a final assurance check for operators to safely run trains, often feeding into the Statement of Compatibility (SOCAT).
Key details regarding the Summary of Compatibility:

• Purpose: Ensures rolling stock works safely with Network Rail infrastructure, covering electromagnetic, gauge, and power compatibility.
• Requirement: Mandatory when introducing, modifying, or transferring (cascading) trains.
• Key Components: Involves identifying relevant stakeholders, building a compatibility matrix, and ensuring compliance with standards like GERT8015 for electromagnetic compatibility.
• Process: The proposer of the change (e.g., train operator) must complete the compatibility assessment, often resulting in a Statement of Compatibility (SOCAT) or similar authorization.

The NRSC is crucial for managing technical risk and ensuring that new or modified equipment does not negatively impact network safety.

 

[Tilting007]

SoC please?

Apologies - thanks to hexagon789!

 

[jfollows]

Apologies - thanks to hexagon789!

System on a Chip in my world, but I didn’t think it was that!

 

[43096]

The NMT can run at MU and the LSL will be the same, so not much - circa 30 miles total of 125mph between Euston and Weaver Jn.
Certainly plenty of 115/120..

And any other HST, presumably.

 

[Russel]

Lots to gain if the 75mph sections on the slow lines were increased…

That's nothing to do with the 730's though, is it?

 

[Tilting007]

That's nothing to do with the 730's though, is it?

It is the same gain than them running at MU speeds where the linespeed is below 110mph - a linespeed improvement…

 

[Tilting007]

And any other HST, presumably.

If there are any others?

 

[Bald Rick]

Lots to gain if the 75mph sections on the slow lines were increased…

But there’s no plans for that?

 

[Tilting007]

But there’s no plans for that?

There is at both the bottom end south of Amington and the north end on the Up linked to Handsacre…

 

[Bald Rick]

There is at both the bottom end south of Amington and the north end on the Up linked to Handsacre…

Ah, sorry I thought you were referrign to the whole WCML! Especially Rugby - Northampton.

 

[Tilting007]

No! That is bad enough at 75mph

 

[Russel]

It is the same gain than them running at MU speeds where the linespeed is below 110mph - a linespeed improvement…

No I get that, but my post was in response to the suggestion of uprating the 730 to operate above 110mph rather than infrastructure upgrades...

 

[Markuk]

I'm surprised there's no EPS line speeds on the 75mph parts of the slow lines, even Pendolinos are limited to 75 between Northampton and Rugby

 

[43096]

If there are any others?

Yes. The 125 Group’s preserved set.

 

[edwin_m]

I'm surprised there's no EPS line speeds on the 75mph parts of the slow lines, even Pendolinos are limited to 75 between Northampton and Rugby

There are many other factors that need to be considered when setting the speed besides curvature, most of which would cost money to resolve. For a non-routine movement such as this, either nobody ever considered providing an EPS speed, or it was looked into but one or more of the other factors made it not worth doing.

 

[andy33gmail]

Isn't it a rule about having a non passenger zone at the front and rear of units allowed 125 mph? Hence why Voyagers and to an extent 80x are a bit wasteful of space. Older trains either had two power cars or an engine and DVT.

“Could passengers in the front part of the train move to the next carriage, since this service is running late”

 

[whoosh]

Isn't it a rule about having a non passenger zone at the front and rear of units allowed 125 mph? Hence why Voyagers and to an extent 80x are a bit wasteful of space. Older trains either had two power cars or an engine and DVT.

A rule, or standard, came about from the Polmont crash in the 1980s, where a push/pull class 47/DBSO set hit a cow and derailed with the DBSO leading. A DBSO was a 'Driving Brake Standard Open' Mark 2 coach with a driving cab.
Following the crash, trains with passengers in the leading vehicle were limited to 100mph - which explains the Driving Van Trailers (DVTs) that entered service on the West Coast (Mark 3s) and East Coast (Mark 4s) which operated on trains which went 110mph and 125mph respectively.
Later, there was a relaxation, and passengers were allowed, but not in the front third of the vehicle, and the first so many seats had to be backwards facing (Voyagers, Meridians and Pendolinos). On Meridians there was a notice in the galley end vehicle that only one person was allowed between the external crew doors and the internal door to the driving cab (as this was the crumple-zone!).
I think there has been a further relaxation if certain crashworthiness conditions are met.

A train with a corridor connection on the front - effectively a full height hole - would struggle to comply.

There are other factors with an upgrade to speed to consider - Class 717s were being tested to raise their speed from 85mph to 100mph. There was a sticking point with the windscreen wiper being able to function correctly - not lifting off the screen at the higher speed - which needed to be addressed.
I have not heard anymore about the test runs that were done on 717s - it seems to have gone very quiet, so don't know if that was actually resolved.

I seem to remember class 373 Eurostar sets were only allowed 110mph on the ECML when they ran domestic Leeds services.
So no guarantee that high speed stock can run at 125mph on classic lines.
Something to do with OHLE power limitation I think.

There was a limit on how many 373s could run at a time in each electrical section, yes.

I think there may have been a limitation of the catenary and pantograph relationship as well, in that the pantograph was designed to run on highly taut French catenary at high speed, and so the upward force it had was set up for that. The ECML catenary, with it's different parameters - with the contact wire drooping between each stanchion - I don't think it was considered able to take the force of the 373's pantograph at high speed, and so a 110mph restriction was put on them.

I may have got that wrong, but I seem to recall that as an issue as well as the power limitation (the horsepower they had compared to a class 91 was in a different league!).

 

[Bald Rick]

There are many other factors that need to be considered when setting the speed besides curvature, most of which would cost money to resolve. For a non-routine movement such as this, either nobody ever considered providing an EPS speed, or it was looked into but one or more of the other factors made it not worth doing.

It was ruled out very, very early on during West Coast Route Mod.

 

[LNW-GW Joint]

I'm surprised there's no EPS line speeds on the 75mph parts of the slow lines, even Pendolinos are limited to 75 between Northampton and Rugby

There are many other factors that need to be considered when setting the speed besides curvature, most of which would cost money to resolve. For a non-routine movement such as this, either nobody ever considered providing an EPS speed, or it was looked into but one or more of the other factors made it not worth doing.

The SRA (in mid-WCRM) did say they were investigating implementing EPS speeds on PS 75mph sections like the Northampton loop and the Grand Junction route in the West Midlands (Stechford-Aston-Bescot-Bushbury), but it didn't get anywhere.
They also promised EPS 90mph on the Queensville Curve at Stafford, but it ended up as 85.

 

[Tilting007]

Yes. The 125 Group’s preserved set.

so not too many in total, the scope is very small but LSL challenged very strongly for their HSTs to run at the MUs.

 

[s491]

so not too many in total, the scope is very small but LSL challenged very strongly for their HSTs to run at the MUs.

Romic, WRC, .......

 

[Tilting007]

Romic, WRC, .......

so not many as mentioned above, not enough to greatly impact the performance on the WCML, but beneficial anyway. NMT is making good use of them.

 

[Falcon1200]

even Pendolinos are limited to 75 between Northampton and Rugby

I'm surprised by that too, given the usefulness of the Northampton Loop for diversions (as indeed happened to my train, 1M08 0736 Glasgow C-Euston today!) whenever an issue affects the main line between Rugby and Hanslope.

 

[cambsy]

are 805-807’s reliably running at the MU Speeds? I am asking as looking to try out the MU Speeds again, as first time tried, my service didn’t have DAS set up, as was tight turn around for my service at Liverpool Lime Street. I dont want to try sample MU speeds and end up failing again.

 

[Bald Rick]

are 805-807’s reliably running at the MU Speeds? I am asking as looking to try out the MU Speeds again, as first time tried, my service didn’t have DAS set up, as was tight turn around for my service at Liverpool Lime Street. I dont want to try sample MU speeds and end up failing again.

My last 8 trips on them have all been at MU speed.

 

[Paul AC]

I'm surprised by that too, given the usefulness of the Northampton Loop for diversions (as indeed happened to my train, 1M08 0736 Glasgow C-Euston today!) whenever an issue affects the main line between Rugby and Hanslope.

Isn't the 75 mph limit as much due to the 3-aspect signalling and the signal spacing as the state of the track?

 

[Falcon1200]

Isn't the 75 mph limit as much due to the 3-aspect signalling and the signal spacing as the state of the track?

I don't know, sorry, but it is something worthwhile addressing; Having been diverted via Northampton on Friday 13th as per my Post #57, I was again diverted via Northampton on my return north on Tuesday, on 1S45 0827 Euston-Glasgow C!