IEP: 26 metres is too long

[aylesbury]

The current units in the EC cannot pass together on the curve at Gateshead something about the kinetic envelope I think .

 

[asylumxl]

Regarding the discussion of 390s clearing the curve at Gateshead, does anyone have anything other than speculation as to how it was done (e.g. possession of adjacent lines)?

To be honest, it could just be that they were able to travel without issues . An insane idea I know...

 

[TGV]

The current units in the EC cannot pass together on the curve at Gateshead something about the kinetic envelope I think .

Kinematic. Kinetic is pertaining to energy in common use - the energy contained or given by moving objects as a function of their mass and velocity. Kinematic involves the study of motion in conjunction with physical geometry.

The 373/2s couldn't negotiate that curve for the reasons you state - the central overthrow of TGV vehicles is greater than that of Mk4s (and the width of the 373/2 a few mm wider than a Mk4) because the bogie pivot spacing is greater despite the vehicle length being less.

 

[RAGNARØKR]

There are many places that the Good old HST cannot go due to the weight of the train on some structures on routes, this will be no different with IEP.

Not many, with the low axle load of the power cars.
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Was this ever in doubt?

When was the last "go anywhere" train built in the UK?

The fact that a 390 has run from Glasgow to Kings Cross makes me wonder whether the argument that an IEP couldn't clear the curve at Gateshead is froth?

The class 390 power cars, including the end cars, presumably have the standard bogie spacing of 16 metres for 23 metre vehicles. It is the centre overthrow that will be the principal issue with the IEP. The end kick-out is easier to deal with, by tapering.

Continental 26 metre vehicles have the bogies much closer to the ends than UK 23 metre vehicles, which is why the UK stock has a characteristic sound as the wheels go over the rail joints. One consequence is that it puts a lot of strain on the coupling and gangways due to the greater relative movement on curves. The mark 3 gangways get a hammering. This applies even more to IEP.
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Regarding the discussion of 390s clearing the curve at Gateshead, does anyone have anything other than speculation as to how it was done (e.g. possession of adjacent lines)?

To be honest, it could just be that they were able to travel without issues . An insane idea I know...

Could be. Extra length in the end cars has a different effect from extra length in the intermediate vehicles of the IEP.
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Kinematic. Kinetic is pertaining to energy in common use - the energy contained or given by moving objects as a function of their mass and velocity. Kinematic involves the study of motion in conjunction with physical geometry.

The 373/2s couldn't negotiate that curve for the reasons you state - the central overthrow of TGV vehicles is greater than that of Mk4s (and the width of the 373/2 a few mm wider than a Mk4) because the bogie pivot spacing is greater despite the vehicle length being less.

If I recall the Eurostars, which are of course articulated, are 2.82 wide with a bogie spacing of 16 metres.

Given the advantages of articulation, and yes, there are disadvantages too, it is also surprising that this option seems not even to have been entertained.

 

[WatcherZero]

According to the sectional appendix 390's can even be towed on the Southport line if their axles are weighted down. If they can managed that old line (RA6 I think) they can go practically anywhere.

Also makes you wonder what diversionary route they were thinking of when they cleared that.

 

[sprinterguy]

If I recall the Eurostars, which are of course articulated, are 2.82 wide with a bogie spacing of 16 metres.

Unless the Eurostars use offset articulation, as the APT-P did, then the spacing between bogie centres should be 18.7 metres, the same as the length of the carriages.

 

[asylumxl]

The class 390 power cars, including the end cars, presumably have the standard bogie spacing of 16 metres for 23 metre vehicles. It is the centre overthrow that will be the principal issue with the IEP. The end kick-out is easier to deal with, by tapering.

BUt how have you come to this conclusion?

 

[aylesbury]

What I meant to say is,the mkiv stock currently in use on the EC line cannot pass at the same time on the Gateshead curve .It evidently was found that that there could be a chance of a collision and a 10mph restriction was put in place.

 

[ainsworth74]

Given the advantages of articulation, and yes, there are disadvantages too, it is also surprising that this option seems not even to have been entertained.

I believe that's down to Network Rail. They aren't fans of articulation as they don't like what it would do to their track.

 

[RAGNARØKR]

Unless the Eurostars use offset articulation, as the APT-P did, then the spacing between bogie centres should be 18.7 metres, the same as the length of the carriages.

Thanks for this information. The system of TGV articulation is illustrated here. Eurostar are also marked as being 2.82 metres wide. As I understand it, this width is permissible because of the steadier suspension and tighter control of sway movements. If you look at the photograph you will see that many of the suspension components are in the space between the vehicles instead of underneath the floor as in an individual vehicle, which makes it possible to optimise their dimensions.

In my view there could be advantages in making trains in sets of of 5, 6 or 7 articulated units with conventional couplings only at the ends of the sets. In addition to the weight savings the suspension is very much steadier. We have just had a fleet of the Alstom suburban EMUs brough into service and the steadiness is remarkable. The possibility of articulation was seemingly was not explored.
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BUt how have you come to this conclusion?

Which conclusion are you referring to? The standard bogie spacing for 23 metre vehicles is 16 metres. You will draw that conclusion if you put the formulae in a spreadsheet and try different bogie spacings. If they are closer together there will be more kick-out at the ends, so they will need additional tapering. If they are further apart there will be additional overthrow at the centre. End cars can be longer as the outer ends with the cabs can be tapered more. The more the projection beyond the bogie centres, the more the strain on gangways and couplings. Continental 26 metre vehicles therefore tend to have the bogies further apart than the optimum from the KE point of view as centre overthrow is not an issue anyway.

It also stands to reason that all the Pendolino cars would have been built to a 25 metre length if this would have been possible. These things are, or should be, gone into early in the design process. Even then there can be surprises, as has been found when class 158s were introduced to new routes.
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I believe that's down to Network Rail. They aren't fans of articulation as they don't like what it would do to their track.

Are you saying that NR consider that the Eurostars are hard on the track? I would be surprised, as the location of the TGV suspension, between the vehicles would appear to give more scope for optimisation. So even if the Eurostars were wearing the track, would this be a feature specific to that class or inherent in articulation per se?

 

[ainsworth74]

Are you saying that NR consider that the Eurostars are hard on the track? I would be surprised, as the location of the TGV suspension, between the vehicles would appear to give more scope for optimisation. So even if the Eurostars were wearing the track, would this be a feature specific to that class or inherent in articulation per se?

Hmm maybe I am getting mixed up but I'm sure I read awhile ago that NR were not fans of articulation. Perhaps someone else can comment?

 

[sprinterguy]

Hmm maybe I am getting mixed up but I'm sure I read awhile ago that NR were not fans of articulation. Perhaps someone else can comment?

I do believe that that is the case. Articulated stock has a higher axle weight than a comparable carriage carried on four axles, if the comparison is to be made by such arbitrary means. Certainly the track access charge for Eurostar carriages, at 9.49p/mile, is closer to the value for a Voyager than for a mark 3 carriage.

 

[WatcherZero]

Network Rails traditional track damage model used to calculate access fees (along with power usage and other factors) basically finds axle weight to be more damaging to track than speed.

Thats changing a little in that now freight access charges will be calculated by comparing the saving in transporting the freight by rail compared to road to try and make them pay more of the costs (previously freight charges were almost completely subsidised by passenger trains).

Since 2007 NR has been using a computer model called VTISM which has been annually improved, last year they added a computer simulation of the damage caused to the rail by the gradual decline in wheel profile for example. They also added research into damage caused to the surface of the track by Yaw which has led to the rollout of stiffer suspensions and fitting of active Yaw management in Desiro vehicles as well as a new rail profile for Pendolinos which extended wheel life.

 

[asylumxl]

Which conclusion are you referring to? The standard bogie spacing for 23 metre vehicles is 16 metres. You will draw that conclusion if you put the formulae in a spreadsheet and try different bogie spacings. If they are closer together there will be more kick-out at the ends, so they will need additional tapering. If they are further apart there will be additional overthrow at the centre. End cars can be longer as the outer ends with the cabs can be tapered more. The more the projection beyond the bogie centres, the more the strain on gangways and couplings. Continental 26 metre vehcles therefore tend to have the bogies further apart than the optimum from the KE point of view as centre overthrow is not an issue anyway.

It also stands to reason that all the Pendolino cars would have been built to a 25 metre length if this would have been possible. These things are, or should be, gone into early in the design process. Even then there can be surprises, as has been found when class 158s were introduced to new routes.

Not remotely what I was talking about. I'm well aware of these things and don't need to use your spreadsheet .

What I was in fact asking is how you came to the conclusion the centre throw of the IEP carriages will be larger than other carriages?

So far all I have found is based on assumptions and have not found any actual evidence to back the claims people have made.

 

[RAGNARØKR]

Not remotely what I was talking about. I'm well aware of these things and don't need to use your spreadsheet .

What I was in fact asking is how you came to the conclusion the centre throw of the IEP carriages will be larger than other carriages?

So far all I have found is based on assumptions and have not found any actual evidence to back the claims people have made.

You need to use the formulae to calculate the centre throw and end kick-out of a vehicle. It is proportional to the square of the distance between the bogie centres. This is 16 metres on a 23 metre vehicle in the UK. If the vehicle is 3 metres longer then either the bogie centre spacing must be increased or there will be a larger kick-out at the ends. Excessive distance between the vehicle ends and the bogie centres also puts a strain on the coupling and gangways. If the bogie spacing of IEP were kept at 16 metres then they would be 5 metres in from the ends. This would cause other problems. I seem to recall reading that the bogie spacing will be 19 metres which sounds reasonable in the light of the above. The IEP width has been given as 2.75 compared to 2.74 for the mark 3, so the additional overthrow has to be accommodated somehow. It helps that due to more accuracy in surveying and maintenance procedures, it has been possible to get away with tighter tolerances.

A "balanced" vehicle is one with the bogies close enough together to minimise the overthrow, but close enough to the ends to enable the vehicle to comply with the KE requirements without excessive tapering. This optimum can be determined by testing the figures on a spreadsheet.

On the continent this is not a problem so the bogies are located as close to the ends as in a 20 metre vehicle in the UK. One result is that the UK vehicles sound different from the continental ones. Vehicles such as mark 3 have a characteristic rhythm.

The spreadsheet that you do not need to use also reveals the interesting conclusion that it is theoretically possible to build a vehicle longer than 20 metres (with a bogie spacing of 14.17 metres), to the full 2.82 width permitted by the old C1 static loading gauge.

 

[asylumxl]

Again, where is this information from?

I've not seen any concrete specifications that specify things such as the bogie spacing.

 

[swt_passenger]

Again, where is this information from?

I've not seen any concrete specifications that specify things such as the bogie spacing.

I have a downloaded copy of a Hitachi data sheet that was made available on DfT's website a few years back (in 2009), and it clearly gives the bogie centres as 17m. Which seems to me to support the view that the extra length is mostly dealt with by the end taper, as has been quite regularly pointed out.

I've never seen anything mentioning 19m spacing - it might just be an invention by those trying to support their own opinion as to why it can't happen... :roll:

 

[asylumxl]

I have a downloaded copy of a Hitachi data sheet that was made available on DfT's website a few years back (in 2009), and it clearly gives the bogie centres as 17m. Which seems to me to support the view that the extra length is mostly dealt with by the end taper, as has been quite regularly pointed out.

I've never seen anything mentioning 19m spacing - it might just be an invention by those trying to support their own opinion as to why it can't happen... :roll:

Ooohhh...

 

[RAGNARØKR]

Ooohhh...

The Wikipedia discussion page on the subject mentions 18.7 metres. A Network Rail discussion paper relating to double deck 26 metre vehicles gave a figure of 19 metres. A bogie spacing of 17 metres would put the bogies 4.5 metres in from the ends ie 1 metre more than in the mark 3 stock. Not impossible but this means even more taper to clear the envelope restrictions. Mark 3 stock suffers from the problems caused by setting the bogies so far in from the ends, putting strain on the gangway and couplings as the vehicles pass over curved track. An even greater departure from established standard practice could lead to unforeseen and unforeseeable problems - it is moving imprudently into a risk zone. Whichever way this is looked at, 26 metres is too long for the UK system.

If there are not loading gauge restrictions the bogies are placed as close to the vehicle ends as possible, as here on this SNCF vehicle. The figures are for overall length and inside wheelbase.

 

[TGV]

Just to clear up some of this articulated business being thrown about;

- TGV vehicles have single pivot articulation (in the centre of the bogie), not the same as the APT set up. One vehicle has a "Male" connection which connects with the "female" part of the adacent vehicle. That adjacent vehicle also "owns" the suspension which is "downstream" of both connections therefore both are fully sprung over the primary and secondary suspension. An intermediate vehicle will have a male connection at one end and a female at the other. End vehicles will have a conventional bogie at one end, and either a female or male depending on which end of the set it's located. The whole thing is controled with yaw and body-control dampers at the bogie and also high up linking the tops of the adjoining vehicles just under cant-line level (which you can see in the photos linked earlier in this thread).

- The axle loading of TGV varies *slightly* between axles, but is around 17t in line with the limits for LGV, and indeed standard high speed line loadings. Power cars with their conventional bogies, weigh 68t or thereabouts, no matter what flavor of TGV is in question, including Eurostar.

- They are very rigid in formation. Very good for high speed (and VERY high speed) stability and also at resisting jack-knifing in the event of a derailment. However the trade-off here is that tight curves can be an issue compared to conventional stock. Perhaps this and the slightly higher axle loadings compared to a Mk3 are what NR were referring to when discussing "track-friendliness" but I've not spoken to anyone on that issue.

 

[RAGNARØKR]

The figure given is £365 million for the East Coast Main Line. The cost for the GWML has been soaked up into the electrification works.
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I have a downloaded copy of a Hitachi data sheet that was made available on DfT's website a few years back (in 2009), and it clearly gives the bogie centres as 17m. Which seems to me to support the view that the extra length is mostly dealt with by the end taper, as has been quite regularly pointed out.

I've never seen anything mentioning 19m spacing - it might just be an invention by those trying to support their own opinion as to why it can't happen... :roll:

26 metre vehicles on the continent have a bogie spacing of 20-21 metres between centres, and no tapering at the ends. If the IEP spacing really is 17 metres, that means the bogies are 4.5 metres in from the ends, which needs to be accommodated by serious tapering. These outer areas are not a good place for luggage unless secure lockers are to be provided.

Goodness knows what such a close bogie spacing and long overhang will do for the dynamics of the vehicles. It should be interesting.

 

[jimm]

The figure given is £365 million for the East Coast Main Line. The cost for the GWML has been soaked up into the electrification works.

Oh really. And this figure for the ECML comes from where? And is for what specific work?

And if the cost for the GWML has "been soaked up into the electrification works" then where is all the work related to your beloved kinematic envelope actually taking place?

Just because you make a statement like this - unsurprisingly without any sources, same as your initial claim of a "major infrastructure upgrade", which you have never been able to justify - proves nothing.

Especially when, as I have said before, I am unaware of a single instance of Network Rail carrying out any work anywhere on the the GWML on lateral clearances that might conceivably be related to accommodating the operation of 26m coaches. There are lots of bridges being knocked about to improve vertical clearances, more new bridges on the way, or track being lowered as another way to create space for wires but that's all - work on vertical clearances.

Anyone else out there know of anything going on or planned on the GWML that looks like it has anything to do with lateral clearances? As RAGNARØKR is clearly never ever going to tell us where all these now supposedly hidden millions (how convenient) are being spent.

 

[D365]

Mightn't the "£365m" ECML works have been soaked into the £240m upgrade? Obviously not but just a though.

 

[RAGNARØKR]

Oh really. And this figure for the ECML comes from where? And is for what specific work?

And if the cost for the GWML has "been soaked up into the electrification works" then where is all the work related to your beloved kinematic envelope actually taking place?

Just because you make a statement like this - unsurprisingly without any sources, same as your initial claim of a "major infrastructure upgrade", which you have never been able to justify - proves nothing.

The figure is for clearance works. You can rely on where it comes from. The same point of origin could not give a figure for the corresponding work on the GWML as this is aggregated into the cost of the electrification and other things that are happening. The work will have to take place one way or another before the longer vehicles can run. I cannot give you specific locations but if you look carefully at the GWML you can see where they are likely to be. You are right in that there should not be clearance problems on the main line between Westbourne Park and Bathampton but there is more to the route than that.

Especially when, as I have said before, I am unaware of a single instance of Network Rail carrying out any work anywhere on the the GWML on lateral clearances that might conceivably be related to accommodating the operation of 26m coaches.

Have you scrutinised all the relevant documents, drawings, etc? Do you have access to them?

There are lots of bridges being knocked about to improve vertical clearances, more new bridges on the way, or track being lowered as another way to create space for wires but that's all - work on vertical clearances.

Whilst the GWML is generally built with easy curves, there are locations on it where the curvature is tight, as you can see if you have a look on Google. It is impossible to accommodate longer vehicles on the system without clearance works at the pinch points. Of course if the track layouts are being completely rebuilt and there is space to make changes, then the costs can be soaked up, but it does not mean that there are none. It is also possible to accommodate longer vehicles by a reduction in tolerances, but this requires a commitment to maintaining the infrastructure to tighter tolerances in the future, which also carries a cost. The figures will no doubt emerge in the fullness of time. As is so often the case, they will turn out to be more than those promoting the project led everyone to believe at the outset.

 

[tbtc]

Anyone else out there know of anything going on or planned on the GWML that looks like it has anything to do with lateral clearances? As RAGNARØKR is clearly never ever going to tell us where all these now supposedly hidden millions (how convenient) are being spent.

All of the "industry experts" regularly cited as being IEP-critics don't appear to have spotted any "significant infrastructure upgrades" in their lists of things to criticise IEP for - odd that.

 

[RAGNARØKR]

All of the "industry experts" regularly cited as being IEP-critics don't appear to have spotted any "significant infrastructure upgrades" in their lists of things to criticise IEP for - odd that.

The cost and the complexities of bi-mode are enough to be getting on with as reasons to criticise. And the IEP has not succeeded in getting rid of powerful underfloor engines. Then there is the issue that other manufacturers never had the opportunity to tender on the basis of the final specification which was very different from that in the invitation to tender.

But if you do not think this is a problem, make yourself a model using a dinner plate and a 30cm ruler marked in centimetres, and measure the offset as you increase the length of the chord ie the distance between where the rim crosses the ruler. Plot the result on a graph.

I have seen no discussion either of the implications of running 26 metre carriages with a 17 metre bogie spacing on the dynamics of the vehicles. That could be really interesting.

This project has the makings of another fiasco like the Danish IC4 train.

 

[jimm]

And no surprise, the same old broken record...

Have you scrutinised all the relevant documents, drawings, etc? Do you have access to them?

What have documents go to do with it? If you actually bothered to read what I wrote, I said I hadn't seen any work taking place that might fit the bill when it came to improving lateral clearances and went on to ask if anyone else had seen any work going on that might conceivably have anything to do with lateral clearances to allow use of 26m coaches - as opposed to all the work already going on out there right now to increase vertical clearances for electrification, where a trip down the line from Oxford to Paddington will reveal bridges already completed and others being worked on - and contracts have been let for replacements elsewhere.

Just in case you have forgotten, you are the person who announced here that there would be a "major infrastructure upgrade" in order for IEP to operate. Have you seen any documents or drawings to justify your statement? I'm guessing not, since you have still failed to stand it up weeks later.

This project has the makings of another fiasco like the Danish IC4 train.

No it doesn't, it's not being built by Ansaldo-Breda. See also Fyra high-speed trains for Belgium and the Netherlands and BM72 emus in Norway.

 

[asylumxl]

No it doesn't, it's not being built by Ansaldo-Breda. See also Fyra high-speed trains for Belgium and the Netherlands and BM72 emus in Norway.

Don't have to go that far to find out about the dodgy practices of Ansaldo-Breda. The West Midland trams fiasco says it all.

 

[RAGNARØKR]

If you actually bothered to read what I wrote, I said I hadn't seen any work taking place that might fit the bill when it came to improving lateral clearances and went on to ask if anyone else had seen any work going on that might conceivably have anything to do with lateral clearances to allow use of 26m coaches - as opposed to all the work already going on out there right now to increase vertical clearances for electrification, where a trip down the line from Oxford to Paddington will reveal bridges already completed and others being worked on - and contracts have been let for replacements elsewhere.

Just in case you have forgotten, you are the person who announced here that there would be a "major infrastructure upgrade" in order for IEP to operate. Have you seen any documents or drawings to justify your statement? I'm guessing not, since you have still failed to stand it up weeks later.

This discussion really is making you angry. If the people driving this project have got this wrong, and there are many reasons to suspect that they have, then you, as a user of the line are going to have to live with the consequences. The length issue is only one of several question marks over the IEP, and they have been widely discussed elsewhere. At the very least, passengers can expect to be confronted with a long period of teething troubles as these very complex trains settle down and the engineers learn how to deal with them.

You say that you have seen no work in progress relating to lateral clearance, but what sort of work would you expect to see as you travelled past? The work involved - realigning of tracks - would require a blockade, so you are not going to see it on your way in to work.

The original information was in a report, if I recall in Railway Gazette, that referred to various infrastructure works, including construction/modification of depots, and the figure was about £700 million. But I cannot find the reference now. However, the figure of £345 million for ECML which can be trusted is consistent with that overall cost. Whether you call it major depends on what you call major, but it would pay for a lot of trains, for instance.

You can be sure that if it had been possible to run larger vehicles on the system previously, it would have happened. GW got a tranche of oversized Networkers to make the best use of the loading gauge. If you think that running longer vehicles on a tight system is a simple matter, try the plate and ruler test. Get a dinner plate and a ruler, and plot the offset against the distance between where the ruler crosses the rim of the plate as you move the ruler in from the edge.

There seems to be uncertainty about the bogie spacing of these vehicles with various figures being quoted. The normal bogie spacing for a 26 metre vehicle is 20 metres or more ie as close as possible to the ends. There are good reasons for that. A spacing of 18.7 metres will give a similar centre throw to Eurostar, but anything less opens up another set of uncertainties. If, as someone has suggested, the spacing will be 17 metres on the IEP, the exepct, amongst other things, problems with on dynamic performance. The interaction at the interface between adjacent vehicles is critical to ride quality, as was discovered when the mark 4 stock first came into service. The greater the end overhang, the more the movement and stresses at the vehicle ends.

The almost 200 year history of engineering design on the railway is littered with failures. These have almost invariably come about when the designers have attempted to do something that was too different from what had been done previously. In some respects the railway environment is one of the harshest on the planet. Even small modifications can give rise to problems that seemingly pop out from nowhere. The way that IEP has been approached is a recipe for a failure of this kind.

 

[The Ham]

At the very least, passengers can expect to be confronted with a long period of teething troubles as these very complex trains settle down and the engineers learn how to deal with them.

Which is perhaps why the IEP's are starting to be built in 2015, full capacity of the factory being reached in 2016 and the trains first being delivered to the GWML in 2017.

It is also the reason that I think that IEP isn't being to the west country so that a lot of testing can be done on them going past Dawlish without having the breakdowns that troubled the Voyagers when they where first running through there.

You say that you have seen no work in progress relating to lateral clearance, but what sort of work would you expect to see as you travelled past? The work involved - realigning of tracks - would require a blockade, so you are not going to see it on your way in to work.

Correct, blockades would not be seen by people on their to/from work, however they would be well advertised on the stations.

The original information was in a report, if I recall in Railway Gazette, that referred to various infrastructure works, including construction/modification of depots, and the figure was about £700 million. But I cannot find the reference now. However, the figure of £345 million for ECML which can be trusted is consistent with that overall cost. Whether you call it major depends on what you call major, but it would pay for a lot of trains, for instance.

£700 million is rather small fry when it comes to railway projects, especially if it includes the cost of the depots for the new trains. Given that the Northern Hub is costing £560 million and is mostly "light" infrastructure projects like electrifying lines as opposed to realigning track.

You can be sure that if it had been possible to run larger vehicles on the system previously, it would have happened. GW got a tranche of oversized Networkers to make the best use of the loading gauge. If you think that running longer vehicles on a tight system is a simple matter, try the plate and ruler test. Get a dinner plate and a ruler, and plot the offset against the distance between where the ruler crosses the rim of the plate as you move the ruler in from the edge.

Why would it have happened before? Why would BR build commuter trains that could only be used on intercity lines or build the IC125's longer than 23m when they didn't have the experience of running 23m long rolling stock and there wasn't quite such a need to use the most capacity of the lines?

The almost 200 year history of engineering design on the railway is littered with failures. These have almost invariably come about when the designers have attempted to do something that was too different from what had been done previously. In some respects the railway environment is one of the harshest on the planet. Even small modifications can give rise to problems that seemingly pop out from nowhere. The way that IEP has been approached is a recipe for a failure of this kind.

You are partly true again, however there are also a lot of successes as well. Also there are some project like the APT is that a failure or a success? On one had it was a failure as no BR built trains used all the technology, on the other hand without it there would be no tilting trains, no IC125's and no IC225's as such were there were enough successes that it could be classed as an overall success?

If passenger services had be stopped as soon as there had been the first passenger death (clearly chalked up as a failure and fairly early in the process of passenger travel) then the railways would have gone the way of the canals a long time ago.

Likewise many of the other failures which have happened have caused lessons to be learnt and progress to be made and for the railways to be safer, more reliable and more attractive to passengers to use than the pioneers of the railways could have ever conceived.

If we relied on only ever building what was safe from any risk then we'd be running a railway which didn't look much different from that in the 60's, which appears to be what you would like it to be like.