807/805 Speeds

[Bald Rick]

Yes the new speeds are live.

 

[Railperf]

Great news!

 

[cambsy]

Im looking forward to seeing what the ride and performance is like with the MU speeds. I think there will be a lot of accelerating and braking, to keep to the new MU speeds profile, and the ride will be lively curving at the higher speeds.

 

[LNW-GW Joint]

Judging from the new Sectional Appendices, there are still some differential EPS speeds shown (eg through Rugby).
Is there actually any likelihood of a class 221 still with active tilt coming through?
It's similar at Leighton Buzzard/Linslade (differential EPS speeds but no MU).

While there are certainly some 125mph MU sections (eg Crewe-Weaver Jn), the predominant MU speed seems to be 115mph and only fractionally above the PS 110.
Even the new TV4 section (Tamworth-Armitage) is just 115 MU, and with no MU at all Nuneaton-Tamworth.
There's also no MU speeds for about 11 miles from Whitehouse Jn (Shugborough) through Stafford to past Norton Bridge.

"Handsacre Jn (future site of)" is marked on the charts at 120m30c, which will dominate operations one day.

 

[The Planner]

Judging from the new Sectional Appendices, there are still some differential EPS speeds shown (eg through Rugby).
Is there actually any likelihood of a class 221 still with active tilt coming through?
It's similar at Leighton Buzzard/Linslade (differential EPS speeds but no MU).

While there are certainly some 125mph MU sections (eg Crewe-Weaver Jn), the predominant MU speed seems to be 115mph and only fractionally above the PS 110.
Even the new TV4 section (Tamworth-Armitage) is just 115 MU, and with no MU at all Nuneaton-Tamworth.
There's also no MU speeds for about 11 miles from Whitehouse Jn (Shugborough) through Stafford to past Norton Bridge.

"Handsacre Jn (future site of)" is marked on the charts at 120m30c, which will dominate operations one day.

It was never going to be substantial amounts of non EPS 125, even 120.

 

[Railperf]

It was never going to be substantial amounts of non EPS 125, even 120.

Ironic that this was mainly a speed board changing exercise to suit the acceleration profile of the 805/807 after it was claimed Virgin insisted that no other trains be allowed to do 125mph on the WCML to give its tilting trains a competitive advantage over any other TOC. But now its successor has gone down the path of opening up higher speeds to all.
I think I was told that higher MU speeds could have been achieved with some geometry improvements - but making those changes was going to cost more money, and would limit where the Pendolino's could tilt - further reducing their speed advantage - especially as the Class 390's are slightly slower accelerating off the mark than some newer stock.

 

[FGWHST43009]

Ironic that this was mainly a speed board changing exercise to suit the acceleration profile of the 805/807 after it was claimed Virgin insisted that no other trains be allowed to do 125mph on the WCML to give its tilting trains a competitive advantage over any other TOC. But now its successor has gone down the path of opening up higher speeds to all.
I think I was told that higher MU speeds could have been achieved with some geometry improvements - but making those changes was going to cost more money, and would limit where the Pendolino's could tilt - further reducing their speed advantage - especially as the Class 390's are slightly slower accelerating off the mark than some newer stock.

Could that be revisited in future, particularly for bits where HS2 trains will be operating and when the Pendolinos are life-expired?

 

[Railperf]

Could that be revisited in future, particularly for bits where HS2 trains will be operating and when the Pendolinos are life-expired?

I think that is the eventual plan, but clearly that can is being kicked further down the road as we struggle to get hs2 open to Birmingham and through to Handsacre.

On the other hand, there is a train manufacturer that does offer high speed and tilt in one package but was not selected - because tilt was never specified once off the high speed line.

 

[Ellis101]

Is the new MU speed profile only south of Weaver Jn?

Or does it include parts of South Parkway - Weaver Junction as well?

 

[hexagon789]

Is the new MU speed profile only south of Weaver Jn?

Or does it include parts of South Parkway - Weaver Junction as well?

As far as Weaver Jcn only.

EPS only extends to Sutton Weaver, around 4 miles after the line to Runcorn and Liverpool has diverged from the WCML.

Beyond that it's plain PS speeds only.

 

[GhostManDN91]

I'm guessing there's no MU speeds between Weaver Jct and Preston then?

 

[Toby268]

I'm guessing there's no MU speeds between Weaver Jct and Preston then?

No, there is not

 

[Bevan Price]

Is the new MU speed profile only south of Weaver Jn?

Or does it include parts of South Parkway - Weaver Junction as well?

Nothing above 90 mph between Weaver Jn and Runcorn in either direction. (Southbound, I think you can start to accelerate above 90 just before you reach the actual junction.)

 

[Sorcerer]

On the other hand, there is a train manufacturer that does offer high speed and tilt in one package but was not selected - because tilt was never specified once off the high speed line.

Which manufacturer? With Alstom the Pendolino technology isn't suitable for speeds over 250km/h, and I'm not sure they offer other tilting technology.

 

[Railperf]

Which manufacturer? With Alstom the Pendolino technology isn't suitable for speeds over 250km/h, and I'm not sure they offer other tilting technology.

Alston's Acelia liberty spec seemed to claim a top speed of 300 km/h with tilt and 360km/h non-tilt. Though the US version max tilt angle is only 6.5 degrees - less than our Pendolino's and Voyagers.

 

[hexagon789]

Alston's Acelia liberty spec seemed to claim a top speed of 300 km/h with tilt and 360km/h non-tilt. Though the US version max tilt angle is only 6.5 degrees - less than our Pendolino's and Voyagers.

Super Voyagers only tilt 6 degrees so thats comparable with that, but Pendolinos are indeed greater at 8°

 

[Pendomonium]

Ironic that this was mainly a speed board changing exercise to suit the acceleration profile of the 805/807 after it was claimed Virgin insisted that no other trains be allowed to do 125mph on the WCML to give its tilting trains a competitive advantage over any other TOC. But now its successor has gone down the path of opening up higher speeds to all.
I think I was told that higher MU speeds could have been achieved with some geometry improvements - but making those changes was going to cost more money, and would limit where the Pendolino's could tilt - further reducing their speed advantage - especially as the Class 390's are slightly slower accelerating off the mark than some newer stock.

I have never, ever, come across this VT 125 only claim. The whole point of EPS 125 running was the limiting factors of the WCML geometry requiring a specific response in the form of tilting trains being allowed to run a specific higher speed where allowed in order to increase train frequency & lower journey times. Were there any serious competitors on the WCML that would have benefited from EPS running? Higher MU speeds on the WCML I really don't care for. The safety margins have dictated the step down speeds to the key areas of PS running where risk of overspeed needs mitigating & that risk is very real. The MU speeds on the WCML don't appear to be for all at all. I know that LNR are not authorised to use them & would assume that any operator would require provision of some form of Driver Advisory System as the overspeed mitigation. It could be that Network Rail will leave MU speed compatibility in the hands of individual TOCs, depending on pre requirements like DAS. It would make sense for the MU speeds to be available for any compliant operator.

 

[LNW-GW Joint]

Plus the imminent deployment on the WCML of class 222 Meridians for Lumo Stirling.
Are they even cleared for MU speeds on the MML?

 

[DaveyJones]

Plus the imminent deployment on the WCML of class 222 Meridians for Lumo Stirling.
Are they even cleared for MU speeds on the MML?

If they're not, Lumo is a subsidiary of the same parent company (First), I can't imagine they'll struggle to get the technical data that they need.

 

[Sorcerer]

Alston's Acelia liberty spec seemed to claim a top speed of 300 km/h with tilt and 360km/h non-tilt. Though the US version max tilt angle is only 6.5 degrees - less than our Pendolino's and Voyagers.

Oh yes, I forgot about that one. The angle isn't quite as good as the Pendolino but might've otherwise been sufficient. However I don't think tilting trains were on the table anyway because most railway companies across the world don't consider them worth the expense compared to non-tilting stock, but that'd be off-topic, and I made a thread that partly discussed that a while back for anyone wanting that discussion. I think Avanti have taken a similar attitude hence the 805/807s being cleared for MU running boards.

 

[Bald Rick]

Plus the imminent deployment on the WCML of class 222 Meridians for Lumo Stirling.
Are they even cleared for MU speeds on the MML?

They’re aren’t any MU speeds on the MML.

222s are not cleared for the MU profile on the WCML, but Lumo will no doubt be addressing that, otherwise they won’t be able to run them in the paths they have allocated.

 

[TT-ONR-NRN]

Which manufacturer? With Alstom the Pendolino technology isn't suitable for speeds over 250km/h, and I'm not sure they offer other tilting technology.

Really? Why not?

 

[Ellis101]

I know that LNR are not authorised to use them & would assume that any operator would require provision of some form of Driver Advisory System as the overspeed mitigation.

Well why would they anyways if the 730/2s and 350s have a maximum speed of 110mph?

 

[Railperf]

Well why would they anyways if the 730/2s and 350s have a maximum speed of 110mph?

The speed profile from Euston steps up earlier to 110mph and beyond under Multiple Unit (MU) and (Tilting) Enhanced Permissible Speeds (EPS) rather than the standard Permitted Speeds (PS). So the 350's and 730's could reach 110mph a tad earlier if allowed to run under the MU profile.

 

[SansHache]

Sorcerer said:
Which manufacturer? With Alstom the Pendolino technology isn't suitable for speeds over 250km/h, and I'm not sure they offer other tilting technology.

Really? Why not?

The maximum speed limitation is a consequence of the train system architecture. The bogie tilt mechanism precludes the mounting of Traction Motors on the bogie. The solution adopted for Pendolino trains (and also Class 221) is to mount the motors on the underframe, driving the inner axle of each bogie via a cardan shaft and right-angled gearbox.

The original 8-car version of the Class 390 had 6 motor cars (12 motors total) and 2 transformer cars, giving a ratio of 37.5% motored axles. With this arrangement it is not possible to achieve a maximum service speed of greater than 250km/h while respecting the mechanical and electrical drive constraints and adhesion limits (44% more power is required to reach 300km/h compared to 250km/h).

300km/h very high speed trains either have a higher ratio of motored axles with distributed traction or utilise power cars with much more larger traction motors.

The mounting of the traction motors on the Class 390 underframe also constrains the remaining available space. In particular there is no room for diesel generator units or batteries, therefore preventing the development of a bi-mode version for the UK market.

 

[Railperf]

I think that is why the Avelia Liberty uses non tilt power cars with tilting coaches - similar to what BR envisaged with Class 91. And probably there is a limit as to how fast those non tilt power cars can negotiate some curves which seems to mean that the passenger vehicles don't require more than the 6.5 degrees of tilt.

Back to 805/807MU speeds. Between Mileposts 20 and 44 a Pendolino can run at a full 125mph all the way in 11.5 min.

Class 221's have to slow round some curves to observe the lower EPS linit so take 30-40s longer.

Non tilt 805/807 running at 110mph have to slow down to 90mph in places for curvature and are 2 min 10 seconds slower than the 390.
Those thinking MU Speeds will make much difference might be pleased to see that it is 20 seconds quicker than at 110mph, but still way behind the 390 and 221!

That's on just one 24 mile section of track!

 

[pokemonsuper9]

And probably there is a limit as to how fast those non tilt power cars can negotiate some curves which doesn't require more than the 6.5 degrees

Isn't the main problem with tilting comfort (i.e. not flinging luggage about) rather than risk of derailment?
If so wouldn't it be reasonable for the cab/power cars to go at whatever speed the tilting accomodation is fine with?

 

[Railperf]

Isn't the main problem with tilting comfort (i.e. not flinging luggage about) rather than risk of derailment?
If so wouldn't it be reasonable for the cab/power cars to go at whatever speed the tilting accomodation is fine with?

Tilting comfort is a consideration, but as mentioned up thread, there are places where there is a risk of overturning unless the centre of gravity is low enough and can be proven not to be a risk.

 

[Pendomonium]

The speed profile from Euston steps up earlier to 110mph and beyond under Multiple Unit (MU) and (Tilting) Enhanced Permissible Speeds (EPS) rather than the standard Permitted Speeds (PS). So the 350's and 730's could reach 110mph a tad earlier if allowed to run under the MU profile.

They would also be able to run faster Rugby - Birmingham.

 

[Railperf]

They would also be able to run faster Rugby - Birmingham.

The problem with that stretch is how many times one gets delayed approaching Coventry on the down and / or Birmingham Int'l.
Heading to London, I rarely get a fast run over the WCML into it through Rugby due to clashing with another path - either because my train was delayed or one coming down the Trent Valley has been.