Should Avanti West Coast's 805/807s Hitachi AT300 sets tilt?

[william.martin]

Let's out this one to bed! A Pendolino's top end acceleration from 90mph is quicker than a class 800/802. But an 805/807 will always lose time having to brake for lower speeds and accelerating back up to 125mph - where the Pendolino can sail through at full speed. That's why the non tilt schedule for Class 805/ 807 is appx 7 minutes slower net timings than the Pendolino schedule from Euston to Crewe.

On the simulator, 30.5 mins Euston to Milton Keynes is achieved following a hybrid speed profile (EPS as existing except for reductions to 100mph at Berkhamsted and 90mph nirth of Leighton Buzzard

Who's idea was it for these trains not to tilt???
I think Hitachi need to go back to the drawing board and get a tilting mechanism sorted. (Obviously it will not happen)

 

[steeevooo]

Who's idea was it for these trains not to tilt???

Presumably every single train manufacturer that bid for the tender - AIUI not a single tilting train was offered.

 

[Railperf]

Was tilting stock specified in the tender?

 

[LNW-GW Joint]

Who's idea was it for these trains not to tilt???
I think Hitachi need to go back to the drawing board and get a tilting mechanism sorted. (Obviously it will not happen)

The killer was when DfT told bidders in 2014 they had to use Hitachi IEPs for ICEC services, and not to go out to tender for anything else.
Other manufacturers, notably the old Alstom, bidding with Virgin/Stagecoach, were keen to bid a pure EMU for the ECML, but once that prospect vanished there was no interest in re-engineering another train for the UK for a small-ish order (13 bi-modes and 10 EMUs) with little prospect of repeat business.
If you recall, Alstom ran a Pendolino up the ECML to demonstrate its capability on the route (in non-tilt mode) - but it was too late.
A significant New Pendolino order, non-tilt on the ECML and a tilt version for the WCML, would have been possible up to that point.

First Group tried to bid non-tilt stock for the aborted 2012 ICWC franchise, so it was no surprise that they went the same way in 2019, with the AT300 already established at several other operators and with UK-assembly, UK clearance and main depots already sorted.
Virgin/Stagecoach never said what its rolling stock plans were, and their bid failed anyway.

And now we have HS2, and HS2 Ltd has never contemplated tilt (or bi-mode) for its classic-compatible trains as it would compromise their High Speed capability on HS2.
So from 2028 (or whenever), non-tilt trains will be the prime movers on the northern WCML, once they are off HS2 infrastructure.

 

[Bletchleyite]

The ECML is far straighter, and so the added comfort of not having a tilt profile is better than a New Pendolino would have been on the ECML.

 

[D365]

Who's idea was it for these trains not to tilt???

Answer below:

Presumably every single train manufacturer that bid for the tender - AIUI not a single tilting train was offered.

In my opinion, this is a complete non-discussion.

 

[william.martin]

The killer was when DfT told bidders in 2014 they had to use Hitachi IEPs for ICEC services, and not to go out to tender for anything else.
Other manufacturers, notably the old Alstom, bidding with Virgin/Stagecoach, were keen to bid a pure EMU for the ECML, but once that prospect vanished there was no interest in re-engineering another train for the UK for a small-ish order (13 bi-modes and 10 EMUs) with little prospect of repeat business.
If you recall, Alstom ran a Pendolino up the ECML to demonstrate its capability on the route (in non-tilt mode) - but it was too late.
A significant New Pendolino order, non-tilt on the ECML and a tilt version for the WCML, would have been possible up to that point.

First Group tried to bid non-tilt stock for the aborted 2012 ICWC franchise, so it was no surprise that they went the same way in 2019, with the AT300 already established at several other operators and with UK-assembly, UK clearance and main depots already sorted.
Virgin/Stagecoach never said what its rolling stock plans were, and their bid failed anyway.

And now we have HS2, and HS2 Ltd has never contemplated tilt (or bi-mode) for its classic-compatible trains as it would compromise their High Speed capability on HS2.
So from 2028 (or whenever), non-tilt trains will be the prime movers on the northern WCML, once they are off HS2 infrastructure.

Interesting, are the voyagers and pendolinos the only tilting trains in the UK?

The ECML is far straighter, and so the added comfort of not having a tilt profile is better than a New Pendolino would have been on the ECML.

Certainly, even if you wore a blindfold you would be able to tell the two apart.

 

[D365]

Interesting, are the voyagers and pendolinos the only tilting trains in the UK?

Yes, and I’d bet a hat on the Pendolinos being the final tilting train in the UK. Once HS2 kicks in, there won’t be a need for tilt.

 

[RobShipway]

Not sure what the point of this thread is, when it has been discussed on other threads previously that due to the acceleration of the AT300 trains, there is no need for them to be able to tilt as they can keep to similar timings, if not better than the class 390 Pendolino's.

Interesting, are the voyagers and pendolinos the only tilting trains in the UK?

Yes, both the Avanti West Coast class 221 Voyagers and Class 390 Pendolino's are the only trains that are in public passenger duties that can tilt.

The British Rail Mk4 coaches however, where designed so that if required tilt equipped bogies could have been retrofitted to these carriages. But as Bletchleyite has mentioned the ECML is fair straighter, so tilting carriages was not required as part of the Inter-City 225 build of trains.

The only other trains that have been on UK rails that have tilted while either in public use or being tested are the APT-E test train and ATP-P (Class 370) I believe. Fiat Ferroviaria (Alstom Ferroviaria) in 1982 brought some design patents of the tilt mechanism from BR, to help that was used to improve their ETR 410/450 trainsets and later helped Alstom, which took over Fiat Ferroviaria in 2000 to develop the Pendolino trains that are in use across Europe.

Yes, and I’d bet a hat on the Pendolinos being the final tilting train in the UK. Once HS2 kicks in, there won’t be a need for tilt.

As has been discussed in many threads, track developments since the class 390 Pendolino's where introduced, has lessened the need for tilting trains.

 

[Bald Rick]

I think Hitachi need to go back to the drawing board and get a tilting mechanism sorted. (Obviously it will not happen)

The trains are being built now. The first two are finished and being tested. You can’t retrospectively fit a tilt mechanism, as the whole train is designed around not tilting. Oh, and the trains would be out of gauge.

 

[MattRat]

Yes, and I’d bet a hat on the Pendolinos being the final tilting train in the UK. Once HS2 kicks in, there won’t be a need for tilt.

Well, they could still be useful away from the HS2 network, like XC or the North Wales coast services, although I understand the downsides and why they didn't order a separate fleet. Also XC doesn't even use their tilt so clearly it's not desperately seen as needed anymore.

 

[Mikey C]

Yes, and I’d bet a hat on the Pendolinos being the final tilting train in the UK. Once HS2 kicks in, there won’t be a need for tilt.

Cross Country have deactivated the tilt on their Class 221s, so once Avanti replace theirs I assume that even if they move to another operator like Cross Country, the tilt will also be turned off.

 

[Railperf]

Not sure what the point of this thread is, when it has been discussed on other threads previously that due to the acceleration of the AT300 trains, there is no need for them to be able to tilt as they can keep to similar timings, if not better than the class 390 Pendolino's.


As has been discussed in many threads, track developments since the class 390 Pendolino's where introduced, has lessened the need for tiltng trains

1. Whoever made the claim about AT300's accekeration is mistaken : A Pendolino's top end acceleration from 90mph is quicker than a class 800/802. But an 805/807 will always lose time having to brake for lower speeds and accelerating back up to 125mph - where the Pendolino can sail through at full speed. That's why the non tilt schedule for Class 805/ 807 is appx 7 minutes slower net timings than the Pendolino schedule from Euston to Crewe.

2. Increasing superelevation (cant) on curves is not new , but it doesn't drastically increase speed. The French have been doing it for decades and BR even followed suit in the late 1980's on some routes.

 

[Bald Rick]

Increasing superelevation (cant) on curves is not new , but it doesn't drastically increase speed. The French have been doing it for decades and BR even followed suit in the late 1980's on some routes.

It’s not the superelevation (cant) that is increased, it’s the cant deficiency. The maximum cant remains the same, but trains are permitted to go round a little quicker. It gains 5-10mph, at the cost of a rather more lively ride. It’s deployed here at the top end of the ECML, parts of the MML and the Berks & Hants (Not sure of anywhere else).

It is used widely in France - I’ve described elsewhere my experience of being in the packed Disco coach of the Calais - Bourg St Maurice overnight ski train as we belted round various curves at high cant deficiency.

 

[Bletchleyite]

It is used widely in France - I’ve described elsewhere my experience of being in the packed Disco coach of the Calais - Bourg St Maurice overnight ski train as we belted round various curves at high cant deficiency.

Germany too - it can be quite hard to walk down trains on curvy routes like the classic Rhein and Mosel.

In essence if a Pendolino can run at 125 without coming off so can an 80x or HS2 unit, it's just a case of being thrown around a bit more.

 

[Bald Rick]

In essence if a Pendolino can run at 125 without coming off so can an 80x or HS2 unit, it's just a case of being thrown around a bit more.

Not necessarily, as a non-tilt pr train going round (say) a bend nominally fit for 100mph at 125mph will have a bigger kinematic envelope.

 

[Bletchleyite]

Not necessarily, as a non-tilt pr train going round (say) a bend nominally fit for 100mph at 125mph will have a bigger kinematic envelope.

As in because it will effectively "tilt" the wrong way? I thought the whole point of the tilt profile was that if two trains were tilted the wrong way and passed they still wouldn't collide?

 

[D365]

1. Whoever made the claim about AT300's accekeration is mistaken : A Pendolino's top end acceleration from 90mph is quicker than a class 800/802. But an 805/807 will always lose time having to brake for lower speeds and accelerating back up to 125mph - where the Pendolino can sail through at full speed. That's why the non tilt schedule for Class 805/ 807 is appx 7 minutes slower net timings than the Pendolino schedule from Euston to Crewe.

How do you know this?

Yes the timings will be slower on sections where the route isn’t being enhanced for non-tilt trains, but I was under the impression that the Hitachi trains will be doing more of the ’stopping’ services.

 

[Bald Rick]

As in because it will effectively "tilt" the wrong way? I thought the whole point of the tilt profile was that if two trains were tilted the wrong way and passed they still wouldn't collide?

Yes to the first point.

And yes, even if two Pendolini were to pass each other both with the tilt the ‘wrong‘ way, they would still be in gauge - ie within it’s designed Kinematic Envelope (KE). That’s what they were designed for.

However if, say, an 80x was going round a 100mph corner at 125mph, it would ‘throw’ the wrong way and therefore potentially be outside its designed KE. Now in theory if an 80x on the adjacent line was doing the same thing there would be no problem. But if what’s coming the other way was a Freightliner at 75mph, there would be quite a bang.

 

[Master29]

They weren't designed that way. They don't need tilting as modern advancements are such that they won't need it. At least that's the line from Hitachi themselves I believe.

 

[cle]

Was there not a programme of works planned to mitigate/remove/expand access to EPS? To level it all out, in as many instances as possible, knowing a few would have to remain 110/non.

 

[Bald Rick]

Was there not a programme of works planned to mitigate/remove/expand access to EPS? To level it all out, in as many instances as possible, knowing a few would have to remain 110/non.

Yes, sort of.

The EPS remains the same. A new ‘MU’ profile would be introduced south of Weaver Jn, which the 80x (and various other units) will use. Only about a quarter of it matches the EPS profile though, and a third has no change from the PS profile.