Class 800/1 Design Question

[RichW1]

Hi All, I am wondering why on Earth the IEP trains have chamfered bodysides? The last time I checked, they were never going to tilt, so why are we making the interior space smaller than a mark 3 when the IEP should be exactly the same profile?

I have looked at the videos and one takes you inside the actual train in Japan and the sides definitely slope inwards. I am very confused, can someone with technical knowledge help... that said I find any reason unforgivable on a non-tilt train that will be with us for 50 years!

Secondly, does anyone working with inside knowledge know if Network Rail are actively pursuing 140mph west of Reading and if so do we have a target year in mind?

 

[Ash Bridge]

Hi All, I am wondering why on Earth the IEP trains have chamfered bodysides? The last time I checked, they were never going to tilt, so why are we making the interior space smaller than a mark 3 when the IEP should be exactly the same profile?

I have looked at the videos and one takes you inside the actual train in Japan and the sides definitely slope inwards. I am very confused, can someone with technical knowledge help... that said I find any reason unforgivable on a non-tilt train that will be with us for 50 years!

Secondly, does anyone working with inside knowledge know if Network Rail are actively pursuing 140mph west of Reading and if so do we have a target year in mind?

Possibly to do with the 26 Mtr. lenth of the vehicles? (Presuming you meant towards the ends of the coach?)

 

[RichW1]

No Actually meant through the whole length of the vehicles. They slope from bottom to top! I do not understand this as we lose space on an old mark 3. These are like Mark 4 coaches which I cannot understand at all. We shouldn't be losing space with a non-tilt model.

 

[RobShipway]

Could it be that they are designed like that so in the future, they can have tilt facilities added at a later date so that they could then do the 140mph?

 

[class26]

Could it be that they are designed like that so in the future, they can have tilt facilities added at a later date so that they could then do the 140mph?

They don`t need tilt to do 140 mph on the GWML, just in cab signalling. Similarly on the ECML

 

[NotATrainspott]

The IEPs aren't designed to tilt in any form. There might be a small amount of narrowing at the top but the pictures I've seen still look much more like a Mk3 than a Mk4 or a Pendolino.

 

[RichW1]

They are already 140mph capable without tilt. I was always under the impression that the only reason to slope sides was to tilt for faster speeds around curves, but as far as I am aware there are no plans at all for these trains to be deployed anywhere, where tilt is going to be required.

We already have a restrictive loading gauge as said, so I don't see any benefit in making the public lose space. I will place a link which shows this....

 

[LNW-GW Joint]

Secondly, does anyone working with inside knowledge know if Network Rail are actively pursuing 140mph west of Reading and if so do we have a target year in mind?

As I understand it, the GW electrification now going up is designed for 140mph operation (Series 1 OHLE).
The future signalling on the route (ERTMS) will also be 140mph-capable.
IEP will be 140mph-capable.
But that does not add up to a plan to introduce 140mph trains, which will require additional infrastructure and systems upgrades.
IEPs may be tested at that speed as part of the acceptance process (as were Class 91/Mk4 on the ECML).
The critical path is probably the delivery of ERTMS, which will initially be an overlay on the fixed signalling (ie not critical to the introduction of IEP at 125mph).
The ECML ERTMS scheme, on the other hand, replaces the fixed signalling south of Doncaster in 2020.
It may well be that the ECML is the first route to get 140mph in-service running.
But it must come well down the list of priorities at the moment, with all the infrastructure changes in prospect.
Then there's the possibility of higher Pendolino speeds on the WCML using TASS.
That will come up again during the next ICWC franchise bid next year.
So in summary, "not in CP5" (2014-19).

 

[RichW1]

Many thanks indeed for that LNW-GW! Much appreciated, now I know where we are.

As for the design, here's the link....look at the interior from 1min 10sec. The sides look slightly and un-necessarily sloped to me...

https://www.youtube.com/watch?v=8-EzmrWjO8c

 

[swt_passenger]

Many thanks indeed for that LNW-GW! Much appreciated, now I know where we are.

As for the design, here's the link....look at the interior from 1min 10sec. The sides look slightly and un-necessarily sloped to me...

https://www.youtube.com/watch?v=8-EzmrWjO8c

A number of existing classes have a slight body taper that is nothing to do with tilt, but to allow for safe operation with degraded suspension. I think that's also the case here, the sides are pretty near vertical even if not perpendicular, so it isn't a future proofing for tilt.

 

[Ash Bridge]

No Actually meant through the whole length of the vehicles. They slope from bottom to top! I do not understand this as we lose space on an old mark 3. These are like Mark 4 coaches which I cannot understand at all. We shouldn't be losing space with a non-tilt model.

Just another thought, they appear to use the same body design (albeit longer and with different door configuration) as the class 395 Javelins, could the reason be to design a standard adaptable body shell as BR did with the mk3 to keep production costs as low as possible. The same shell could be used for a variety of future designs also?

 

[RichW1]

Safe operation with degraded suspension? That is an education for me, I was not aware of such a requirement; safety factor that is un-necessary? I think the slope become clearer at 1 Min 22sec I just would have thought a straight side could be designed fully safe as the Shinkansen High-Speed trains are very vertical and operate fine with much higher spec.

The same is true of mass designs Ash Bridge refers to...why not make the mass designs with more space as per the mark 3. Why when time goes forward are we making things worse in design?!

Take a look at the bottom of the train...why is the skirt at the bottom not colour coded like the plans and other existing trains? Even the APT has this! I wish we would look at the visual as well as the technical. Still the body sides sloping remain a mystery to me.

 

[cjmillsnun]

Many thanks indeed for that LNW-GW! Much appreciated, now I know where we are.

As for the design, here's the link....look at the interior from 1min 10sec. The sides look slightly and un-necessarily sloped to me...

https://www.youtube.com/watch?v=8-EzmrWjO8c

Hardly a tilt profile.

Also degraded suspension could be something like an air bag failing at 125 MPH. It happens. Not something unnecessary.

 

[swt_passenger]

They don't slope as much as the entire Electrostar or Turbostar families. They aren't designed to tilt either.

 

[samuelmorris]

I was going to say, doesn't look any more tapered than a Mk 4. I assumed a slightly tapered profile was partly to help with turbulence of passing trains. I hardly notice it on a Mk4 whereas on a Mk3 at 125mph you physically get knocked if you're leaning against the sidewall when another train passes at speed.

 

[RichW1]

Again though, if 186mph Shinkansen trains can run with straight sides, what is our excuse? Airbags and suspension; they have solved this obviously...we just seem to have designed sloped sided trains losing valuable space given our gauge clearance for real apparent reason. These are inferior in space to a mark 3. Like I say have a look at 1min 22 seconds where it becomes quite apparent.

I still don't understand this to be honest. If the Japanese can achieve this and the French, why do we choose to lose space?!! So confused. I would love to speak to the designers and engineers about how this is deemed necessary on tight railway like ours. We need every 10cm we can get!

Samuel Morris, I just saw your post and think you may have a good point there! Maybe it is turbulence indeed, especially if future closing speed are raised, I can see that argument. I know what you mean with the mark 3's and that may well be to mitigate this as you said... think you may have solved the conundrum!

 

[cjmillsnun]

Again though, if 186mph Shinkansen trains can run with straight sides, what is our excuse? Airbags and suspension; they have solved this obviously...we just seem to have designed sloped sided trains losing valuable space given our gauge clearance for real apparent reason. These are inferior in space to a mark 3. Like I say have a look at 1min 22 seconds where it becomes quite apparent.

I still don't understand this to be honest. If the Japanese can achieve this and the French, why do we choose to lose space?!! So confused. I would love to speak to the designers and engineers about how this is deemed necessary on tight railway like ours. We need every 10cm we can get!

Samuel Morris, I just saw your post and think you may have a good point there! Maybe it is turbulence indeed, especially if future closing speed are raised, I can see that argument. I know what you mean with the mark 3's and that may well be to mitigate this as you said... think you may have solved the conundrum!

Shinkansen trains and TGVs run in different conditions to this train.

The part referred to at 1:22 is a coach end. It will be more tapered than elsewhere. The coach is 3m longer than a Mk3 and still has to fit within the loading gauge around curves.

 

[NotATrainspott]

Safe operation with degraded suspension? That is an education for me, I was not aware of such a requirement; safety factor that is un-necessary? I think the slope become clearer at 1 Min 22sec I just would have thought a straight side could be designed fully safe as the Shinkansen High-Speed trains are very vertical and operate fine with much higher spec.

The same is true of mass designs Ash Bridge refers to...why not make the mass designs with more space as per the mark 3. Why when time goes forward are we making things worse in design?!

Take a look at the bottom of the train...why is the skirt at the bottom not colour coded like the plans and other existing trains? Even the APT has this! I wish we would look at the visual as well as the technical. Still the body sides sloping remain a mystery to me.

Just another thought, they appear to use the same body design (albeit longer and with different door configuration) as the class 395 Javelins, could the reason be to design a standard adaptable body shell as BR did with the mk3 to keep production costs as low as possible. The same shell could be used for a variety of future designs also?

http://www.hitachirail-eu.com/at-300-high-speed_47.html

The Class 80x design is from the same AT300 family as the Javelins. The design allows anywhere between 5 and 12 carriages, each between 20 and 26 metres long. Similar components are then used in the AT200 design, which has been selected as for use on the newly electrified routes between Glasgow Queen Street High Level and Edinburgh. Their AT100 design is similar yet again, and that's what they're using to bid for the new London Overground train order.

 

[edwin_m]

I was going to say, doesn't look any more tapered than a Mk 4. I assumed a slightly tapered profile was partly to help with turbulence of passing trains. I hardly notice it on a Mk4 whereas on a Mk3 at 125mph you physically get knocked if you're leaning against the sidewall when another train passes at speed.

The Mk4 body was designed to allow tilting, as when they were built there was an idea of building some tilting ones for the WCML too. The sides of a Mk4 are also thicker than those of a Mk3, which is probably the main reason there is less of a pressure pulse when passing.
--- old post above --- --- new post below ---

Again though, if 186mph Shinkansen trains can run with straight sides, what is our excuse? Airbags and suspension; they have solved this obviously...we just seem to have designed sloped sided trains losing valuable space given our gauge clearance for real apparent reason. These are inferior in space to a mark 3. Like I say have a look at 1min 22 seconds where it becomes quite apparent.

I still don't understand this to be honest. If the Japanese can achieve this and the French, why do we choose to lose space?!! So confused. I would love to speak to the designers and engineers about how this is deemed necessary on tight railway like ours. We need every 10cm we can get!

The Shinkansen and TGV benefit from much more generous loading gauges and they may not even use air suspension anyway.

 

[swt_passenger]

Again though, if 186mph Shinkansen trains can run with straight sides, what is our excuse? Airbags and suspension; they have solved this obviously...we just seem to have designed sloped sided trains losing valuable space given our gauge clearance for real apparent reason. These are inferior in space to a mark 3. Like I say have a look at 1min 22 seconds where it becomes quite apparent.

I still don't understand this to be honest. If the Japanese can achieve this and the French, why do we choose to lose space?!! So confused.

We aren't 'losing space' we are generally designing vehicles to the maximum size that will fit into the structure gauge that already exists on the routes they will operate on, while allowing for all the sway and movement that occurs dynamically at the higher points of the vehicle, and that must be safe under all feasible loading conditions and suspension failure modes (as I mentioned earlier). So the top of the side of any vehicle or unit (or even freight container) will normally be the pinch point, because it moves around more under all conditions.

Has it occurred to you that the 'waist' of the 800/SET may possibly be slightly wider than a Mk 3 coach? Have you seen a cross section of a Mk3 coach that shows it also has a degree of vertical taper?

People have been discussing the reasons for the shape of vehicle bodies in these forums since they started, and the reasons definitely DO account for air suspension failure.

 

[BananaRepublic]

....I do not understand this as we lose space on an old mark 3....
....We shouldn't be losing space with a non-tilt model.

....We already have a restrictive loading gauge as said, so I don't see any benefit in making the public lose space.....

....we just seem to have designed sloped sided trains losing valuable space....
....These are inferior in space to a mark 3......
....We need every 10cm we can get!

I think you have completely overplayed the issue.
There is no meaningful loss of space in these vehicles, especially at standing shoulder height or above.
The vertical taper is minimal and no different (probably less) than on other modern era rail vehicles used in the UK, including those on local and commuter lines.

The real test for the passenger environment in these trains, will be down to the interior design, packaging and quality of finish. Not the design of the train itself.

 

[WatcherZero]

The IEP does taper but only at the carriage ends to help clear its 26m length. This was the same thing BR was planning with the Mk5 design which Hitachi adopted the profile of as BR had already done most of the work to ensure it was cleared on the majority of routes.

 

[Deepgreen]

I don't see any significant narrowing of profile towards the roof level. As has been mentioned they are most reminiscent of the 395s' profile.

 

[Bletchleyite]

I don't see any significant narrowing of profile towards the roof level. As has been mentioned they are most reminiscent of the 395s' profile.

Those with concerns should try riding a 395 - they are surprisingly spacious. Other than the smaller windows the interior is very reminiscent of the Class 350/1 (which also has a very slight taper on the sides, though barely noticeable, but is narrow generally for a 20m unit).

Neil

 

[Ships]

Safe operation with degraded suspension? That is an education for me, I was not aware of such a requirement; safety factor that is un-necessary? I think the slope become clearer at 1 Min 22sec I just would have thought a straight side could be designed fully safe as the Shinkansen High-Speed trains are very vertical and operate fine with much higher spec.

The same is true of mass designs Ash Bridge refers to...why not make the mass designs with more space as per the mark 3. Why when time goes forward are we making things worse in design?!

Take a look at the bottom of the train...why is the skirt at the bottom not colour coded like the plans and other existing trains? Even the APT has this! I wish we would look at the visual as well as the technical. Still the body sides sloping remain a mystery to me.

Fun fact for you, some of the 6ft tunnel clearances on the southern WCML with two tilt failed Pendo's is in the region of less than 10mm!

 

[cjmillsnun]

Fun fact for you, some of the 6ft tunnel clearances on the southern WCML with two tilt failed Pendo's is in the region of less than 10mm!

That's a bit tight.