Channel Tunnel Problem

[Justin Smith]

I think the whole thing is an absolute shambles and I can`t believe anyone is trying to defend Eurostar.
If there really is no way any other electric or diesel loco could be used to extract the errant trains then something is seriously wrong somewhere. So what if a few rules had to be bent to accomplish it. The alternative, of leaving people in a train with no (or minimal) light, water and food, and loads of screaming kids, sounds like my definition of hell. I`d rather have walked 10 miles to the nearest exit, and I mean that.

To add insult to the already considerable injury I heard that Eurostar authorised a car to drive into the tunnel to pick up some famous "super model" (whatever the hell one of those is) but leave all the mere mortals in there.
Does anyone know if this is true ?
If it is true then the officials that authorised it want shooting, or at least be forced to stay in a tunnel with minimal light, no water, food or air conditioning, plus loads of screaming kids, for 10 hours. Personally I`d have to think whether I`d not rather take my chances with the bullets....

 

[91101]

Someone was recalling a similar story on SkyNews, but with slightly less detail. I am slightly sceptical.

Situations such as these are extremely fluid, and one might think that one has an understanding of what is happening but something can change at a moments notice that would completely change any previous assumptions. (Prime example here, we all thought that the first plane that went into the World Trade Centre was an accident untill the second one hit!) so, I will defend their controllers and managers in that they were in a completely exceptional position. It is completely unprecedented for 5 trains to be stopped in the tunnel at any one time.

I think that one of the factors here is there does seem to be a lack of communication between Eurostar and Eurotunnel and Richard Brown explained on Breakfast this morning that once a train is on Eurotunnel infrastructure it is completely under their command.

There has been a growing trend for TOC's and Network Rail to centralise their control functions based on the Network Rail regions, the first of these was the Wessex Intergrated Control Centre at Waterloo, bringing South West Trains and Network Rail staff together. HS1 falls into the Midlands and Continental Network Rail Region, who has a consolidated control at Derby for the "Midlands" side of the operation, bringing together East Midlands Trains and Network Rail controllers, whilst there is a control precence at Ashford IECC for HS1. I believe, that a dedicated control centre, housing Network Rail M&C, Eurostar and Eurotunnel, would help to better co-ordinate incidents like this, and prevent disasters such as this happening again.

 

[Micky Redmire]

All good points, but what you're still failing to acknowledge near instantaneous change in atmospheric conditions. The conditions in tunnel are unlikely to be out of the spec, as are the conditions outside the tunnel. However how do you deal with an almost instant 30 deg C change in temperature and a say 60-70% change in humidity. It's all very well preaching engineering basics, but until you're presented with the conditions in real life you're not going to know for sure.

Insulators or any other component with a voltage stress across it @ several kV that go from cold and dry to very damp quickly is going to struggle!

If it could have been engineered out in a cost effectively manner then it would have been by now. Alstom do have a reasonable heritage with this kit!

As I posted above, this isn't the first time and won't be the last!!

Near instantaneous? Are the tunnels fitted with doors that only open as a train approaches? I wasn't aware of that ..... There will be a measurable temp and humidity gradient, this will vary according to natural ventilation, forced ventilation and the pumping action of trains. Fork lift trucks experience much sharper gradients entering/leaving cold stores.

With regards to "knowing for sure", a good detailed design process will ensure that the unknowns are negligible, but the construction costs will - almost invariably - be more than a performance design where the system is designed to a cost rather than to a spec.

Regarding HV insulators, if dampness is a problem then the arc struck should vaporise the water, problem fixed; this may or may not result in a protective device functioning. If repeated disconnection occurs then duplicate that part of the circuit. Nothing new here, it's been standard practice for decades, but the problems arise when value engineering occurs (or incompetence) and sufficient redundancy is not included within the final design. Up until a couple of days ago, the general travelling public didn't perceive this as a problem, but now they do.

At this stage, we don't have all the facts; hopefully the trains and the tunnels are equipped with sufficient sensors and data loggers to view events leading up to the failures. If not, I sense a sales opportunity .... !

Edit: The Flail carries an article which probably contains some truths and some untruths.

http://www.dailymail.co.uk/news/article-1237102/Pictured-Eurostar-passengers-trapped-channel-hours-trains-break-down.html

 

[bluenoxid]

The trains are covering nearly two miles per minute in the tunnel. There will be a rise but it will be severe. You also have to take into account the changes in humidity too which compound a temperature rise.

To be honest, I would like to see what speed the latter trains were put in at. I would have expected them to drive them in slower to slow down the rate of increase in temperature.

Whilst it has been a debacle and I expect an internal investigation to take place at the very least, these situations are incredibly unusual and tough to work out especially with the limited resources available. Eurostar are unlikely to have a crisis command structure in place that will take them through the night.

 

[captainbigun]

Yes, clearly there will be a temperature and humidity gradient. However a fork lift truck is hardly comparable! No HT, and certainly not changing environments at 100mph!!

It depends what shorts out, most semiconductors don't function too well after a short circuit condition. Bear in mind that an arc won't necessarily occur giving longer short circuit conditions.

Time will tell, but I know those that engineered these vehicles are well versed in the technology.

 

[boing_uk]

I have to wonder if most of the stories of woe and disaster in the tunnel are not of the same ilk as the 25kV live cable flapping over the platform at St Pancras... i.e bobbins.

 

[jon0844]

I can imagine it was unpleasant, but everyone had a seat and the toilets can't have immediately stopped working and people almost about to eat each other after just 10 minutes!

In 2003, we were lucky enough to the be on the last flight that made it out of New York back to London when snow closed the whole city. The downside was that we sat for over 7 hours on the ground waiting to take off.. the plane had to be de-iced numerous times and we coudn't disembark back at the gate or we'd have not left at all (and been stuck in NYC for another 3 days as it turned out).

While they did the de-icing and other things, the air conditioning was turned off. The plane got very hot. We couldn't really move about either, and imagine how many people may have wanted to use the toilet? I think we got one round of water and nothing else.

But, people didn't actually complain or riot. The stories when we returned home might have been somewhat different, but people just accepted the situation and wanted to get home safely at some time.

I can tell you, it's not nice sitting on a plane for the same length of time (almost) that the flight was going to be. Imagine having sat still for that time and then having to do it all again!!

You know what? I'm still here - and when you step off the plane (or off the train), it's amazing how quickly you forget about the ordeal.

Not that I am letting Eurostar off the hook for making a bad situation worse, but when the press are goading people into telling them the worst possible story, you're going to get the 'gasping for air' comments.

 

[Justin Smith]

hopefully the trains and the tunnels are equipped with sufficient sensors and data loggers to view events leading up to the failures.

There`s something deeply ironic here, I speak as an (ex ? ) TV engineer.
TVs used to pretty fixable, till they started adding all this digital protection and monitoring circuitry. Now relatively few TV repair shops remain because the bleedin` things are more computers than anything else. Too complicated for their own good. Just like Eurostars.
KISS, Keep It Simple Stupid (or as simple as possible anyway.....)
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it's amazing how quickly you forget about the ordeal.

I`m pretty sure I wouldn`t forget about it in a hurry........

I come back to my original point, if there really weren`t any other locos (diesel or electric) which could have just pulled the failed trains out of the tunnels then something is most definitely wrong somewhere. So what if they may have had to bend a few rules. The alternative was hardly a zero cost option was it, not to the passengers stuck in purgatory anyway........

 

[captainbigun]

There`s something deeply ironic here, I speak as an (ex ? ) TV engineer.
TVs used to pretty fixable, till they started adding all this digital protection and monitoring circuitry. Now relatively few TV repair shops remain because the bleedin` things are more computers than anything else. Too complicated for their own good. Just like Eurostars.
KISS, Keep It Simple Stupid (or as simple as possible anyway.....)

Unfortunately the complex GTO inverter drives don't lend themselves to simple analogue control. Micro control is a must.
--- old post above --- --- new post below ---

I come back to my original point, if there really weren`t any other locos (diesel or electric) which could have just pulled the failed trains out of the tunnels then something is most definitely wrong somewhere. So what if they may have had to bend a few rules. The alternative was hardly a zero cost option was it.......

Can you reasonably expect a set of circumstances such as this where you have five failed trains? I don't believe you can, so there's no way that there would have been enough suitably equipped locos available. It's a freak event, and whilst clearly unpleasant and something that should be learnt from, it couldn't have been predicted.

 

[jon0844]

I`m pretty sure I wouldn`t forget about it in a hurry........

If you had just survived something where you feared for your life, you would remember. When you've merely been inconvenienced and delayed - you DO quickly forget because you just want to get to your destination.

Now if people really DID fear for their lives then it's a totally different story, but I doubt many really did. They were just tired, annoyed and simply p**ed off.

I think they've also done pretty well compensation wise, but even that wasn't enough for some American tourists who thought the free return ticket was of no use to them! I think they even compared the length of time for a flight from the USA to the delay, as if 11-14 hours is in some way normal for Eurostar!

I'd like to see the media interviewing people who just accepted the problem and got on with it - but they either decided not to wait any longer to speak to the press, or perhaps they don't exist at all. The latter seems unlikely.

 

[Justin Smith]

Unfortunately the complex GTO inverter drives don't lend themselves to simple analogue control. Micro control is a must.
--- old post above --- --- new post below ---


Can you reasonably expect a set of circumstances such as this where you have five failed trains? I don't believe you can, so there's no way that there would have been enough suitably equipped locos available. It's a freak event, and whilst clearly unpleasant and something that should be learnt from, it couldn't have been predicted.

More like a case of lack of flexibility and "can do" attitude, erased by years of sticking exactly to the rules so you don`t expose yourself to the chance of any come back whatsoever, and over regulated Health & Safety B*****ks.
We`d have lost the last war, and every war, with that kind of attitude.
If they can bring a failed spaceship back (Apollo 13) with a bit of out of the box thinking, how come they can`t drag a few trains out of a tunnel ?
It`s pathetic.

 

[Lampshade]

Common sense comes second to Health and Safety these days.

 

[boing_uk]

Quite.. the first and second failures could have been flukes; they are known to happen. Ive had a single major junction fail three-or-four times in a day all for different things, which were symptomatic of another fault.

The fact is, that if you did a ven diagram or something of that ilk of the failed component and all the causes of such, there are quite a few different things it could be.

The biggest failing is not the trains, but the PR effort afterwards and the communication to the passengers during. The stories of the police officers comandeering the PA system and evacuating passengers is nonsense - would they do this on an aircraft? No.

And I cant imagine for the life of me what these people expected to gain by opening the train doors - its not as if there is a huge quantity of fresh air in the tunnel.

"Evacuate people to the service tunnel!". Oh yeah, great move. Stick 400 people in a tube 3m wide; in a real emergency where do these people go then? These police officers are not "heroes"... they are a menace as they could not possibly have understood any hidden risks they may have put passengers in.

"When we got to Calais a baby was taken to hospital in an ambulance. I understand it was a suspected case of pneumonia."

I hardly think that after 7 hours in a warm train, a baby can catch pneumonia... so undoubtedly the child wasnt well prior to the train journey and would probably have been ill at home instead of the train. Or again, its just hype and it was a bit of heatstroke or similar. Although I do agree with the paramedics comment about the train maybe not having oxygen on board - I would have expected an enhanced medkit be available, including a defibrillator and oxygen, for just such occurences.

:roll:

 

[IRIS]

Electrical and electronic systems are subject to "bake and shake" to validate their design. In this case it would have been "freeze and steam". All five locomotives broke down (for the same reason?). This may indicate that the design was inadequately validated for extreme operating conditions.

Validated designs can result in electro-mechanical systems that work under all conditions. The tunnels normally are warm and humid. That leaves a question of how unusual was the weather at the portals? Once in 5 years, 50 years or 100 years?

 

[EM2]

Justin, seeing as we don't know *exactly* which systems failed on which trains, how do you know what should or shouldn't be done to move them?
For example, if the brake circuit is one of those that fails and the brakes have jammed on, how the hell are you supposed to drag a 400m long Eurostar?
I think you're taking a very simplistic view.

 

[Lampshade]

They could have just slowed down or stopped on the entry to the tunnel so the thaw was slower and therefore wouldn't have had such an effect. If the ice had chance to melt slowly the net effect of it would have been the same as if it had been raining.

 

[captainbigun]

They could have just slowed down or stopped on the entry to the tunnel so the thaw was slower and therefore wouldn't have had such an effect. If the ice had chance to melt slowly the net effect of it would have been the same as if it had been raining.

It isn't thought to be ice. It's a case of a very cold surface (likely to be metals and ceramics) being put into a humid environment. Think about getting a cold can of drink out of the fridge on a hot, humid summers day, what happens? Condensation.

Slowing or stopping wouldn't really help without waiting significant time. Is that operationally feasible with the Eurotunnel trains aswell? Nope.

 

[Micky Redmire]

From the Flail

Moreover, according to Eurostar's director of engineering, Nicolas Petrovic, the tunnel is a particularly difficult operating environment for the trains: 'It is hot in there, usually 20C, and because it is under the sea it is very salty too which means there are particular challenges.'

The sea is leaking into the tunnel?

If the problem is snow melting on the underside of the trains, run them through a steam cleaner before entering the tunnel.

Did the tunnel management authorise a train to enter the tunnel when there was another train stopped ahead?

If there is no procedure in place to efficiently recover 5 "dead" trains then why were there 5 trains in the tunnel? If there is a procedure in place to efficiently recover 5 "dead" trains then why didn't it work?

In view of the extended entrapment, step 1 should be to install connection points throughout the tunnels (with secondary supply) to allow the "on-train" services (lighting, aircon, communication etc) to remain live.

Whatever happened, it's all fixable, but it needs engineers to fix it, not bean counters, media people or politicos. Where is Fred Dibnah when you need him?

In closing, it's good to note that Bittern and Sir Nigel Gresley were thundering through the English countryside yesterday.

 

[Justin Smith]

Justin, seeing as we don't know *exactly* which systems failed on which trains, how do you know what should or shouldn't be done to move them?
For example, if the brake circuit is one of those that fails and the brakes have jammed on, how the hell are you supposed to drag a 400m long Eurostar?
I think you're taking a very simplistic view.

I`m not taking a simplistic view, I`m taking a cynical view. That cynical view come from years of dealing with authorities and large companies, both in my business life and out of it. Both of those type of organisations are very bad at flexibility and thinking on their feet "out of the box". On the other hand they`re very good at doing things by the book to avoid any comeback on themselves. That`s the way of the world these days, not that I`m saying I agree with it.

 

[Micky Redmire]

Yes, clearly there will be a temperature and humidity gradient. However a fork lift truck is hardly comparable! No HT, and certainly not changing environments at 100mph!!.

So are we agreed that - unless there are doors are in operation - the temp/humidity change for the Chunnel is not "nearly instantaneous"? I estimate gradient distance of at least 500m. No HT on an LPG fork truck? Really? You need to research. Temp gradient for a cold store can be 41'C over 4m, truck speed can be 20kmh.

It depends what shorts out, most semiconductors don't function too well after a short circuit condition. Bear in mind that an arc won't necessarily occur giving longer short circuit conditions.

Assuming the design is good, why would a vulnerable semi-conductor be exposed to any short circuit condition? That's what protection is for.

Time will tell, but I know those that engineered these vehicles are well versed in the technology

Please produce your evidence

 

[captainbigun]

So are we agreed that - unless there are doors are in operation - the temp/humidity change for the Chunnel is not "nearly instantaneous"? I estimate gradient distance of at least 500m. No HT on an LPG fork truck? Really? You need to research. Temp gradient for a cold store can be 41'C over 4m, truck speed can be 20kmh.

Assuming the design is good, why would a vulnerable semi-conductor be exposed to any short circuit condition? That's what protection is for.
Please produce your evidence

I wasn't considering LPG forklifts, just the plain battery powered variety. (Do LPG fumes and cold stores mix?!). Still, not HT comparable to a 25kV vehicle. I'm sorry, but I still can't see much of a comparison, forklifts and trains are apples and pears.

If protective devices worked all of the time, then you'd never lose any component in this fashion, but we do, that's life.

The evidence is there for all to see, how many TGVs, AGVs etc etc are there in the world!!

 

[bluenoxid]

500m would be done in 15 seconds, so it's not a short timespan as you are trying to put out. You also still have not taken into account the change in humidity which a forklift (which is quite a simple vehicle electronically), would not face entering and leaving a freezer.

 

[Micky Redmire]

I wasn't considering LPG forklifts, just the plain battery powered variety. (Do LPG fumes and cold stores mix?!). Still, not HT comparable to a 25kV vehicle. I'm sorry, but I still can't see much of a comparison, forklifts and trains are apples and pears.

If protective devices worked all of the time, then you'd never lose any component in this fashion, but we do, that's life.

The evidence is there for all to see, how many TGVs, AGVs etc etc are there in the world!!

LPG can be used in cold stores, three way cat required (heat gain into the cold store can be a problem though), HT voltage is typically 20kV, can be as high as 40kV. The point is, these things are designed to be used over demanding temp gradients, as should the E*.

The operation of a protective device should not create risk.

There might be many TGVs and AGVs in the world, but are they reliable?

Having just seen the BBC news, has a component common to all sets been changed recently?

 

[captainbigun]

So LPG forklifts have continous HT at between 20 and 40kV? :?

Yes, TGVs are massively reliable, I believe the MPC figures are exceptional. if it was a crap product, they wouldn't have been sold world wide in such volume.
--- old post above --- --- new post below ---
Anyway, much conjecture here.

I'm sure all will become clear, I certainly will be interested to hear the detail.

 

[Micky Redmire]

So LPG forklifts have continous HT at between 20 and 40kV? :?

At higher engine rpm, effectively yes, although pulsed (it's the current that's very different). The point being that if something simple like a fork truck can operate reliably over an anticipated temp gradient then so should a modern train. Of course, the train should have a higher level of redundancy for critical components, therefore risk of system failure should be much lower.

 

[captainbigun]

Eurostar are advising that they have identified the required modifications and these have begun. Still, no services tomorrow, Monday.

 

[adc82140]

If those stranded in London can be put on a 395 down to Dover & ferry onwards, why can't those stuck in Paris etc be put on TGVs to Calais Frethun & ferry back to the UK?

Or alternatively, why not charter an aircraft or two? Money, that's why.

I've just seen the head of communications of Eurostar on BBC News apologising for the delays. Crocodile tears, methinks.

 

[Electrostar]

Sky News and BBC report that Eurostar is running an emergency service for vulnerable passengers (the elderly and those with children) using a Javelin train to Folkestone, transfer passengers to a ferry and then trains to Paris and Brussels. But they can't provide the same service for London-bound passengers? Why? Surely they can run spare TGVs to Calais Frethun? And why aren't there Eurostar representatives at Paris? Has the situation been made worse because it's a tri-nation company?

 

[Justin Smith]

If those stranded in London can be put on a 395 down to Dover & ferry onwards, why can't those stuck in Paris etc be put on TGVs to Calais Frethun & ferry back to the UK?

Or alternatively, why not charter an aircraft or two? Money, that's why.

I've just seen the head of communications of Eurostar on BBC News apologising for the delays. Crocodile tears, methinks.

Absolutely.
Though a bit of money now, or preferably a bit earlier, would have helped them lose a hell of a lot less money, due to the awful publicity, in the future.
Do these people really know how to run a business ? One has to doubt it......

 

[DaveNewcastle]

I don't want to add to the criticisms of the tunnel operations and I have actually been reflecting on how travel only a few generations ago would have been so awfully worse than this in bad weather (I was discussing the 10-mile interval of horse-drawn stageing posts just a few days ago), but I do like these comments:

. . . . to install [electrical] connection points throughout the tunnels (with secondary supply) to allow the "on-train" services (lighting, aircon, communication etc) to remain live.

Its something we see quite routinely on the exterior of buildings which regularly have vehicles stabling with requirements for on-board electrics. If CEE-form connectors are not already available along the tunnel then that IS a good suggestion.

In closing, it's good to note that Bittern and Sir Nigel Gresley were thundering through the English countryside yesterday.

That irony wasn't lost on me either! (Not that I'm proposing coal burning in long tunnels) Though reading some of the suggestions on here proposing diesel-burning locos in the tunnel then maybe its not so crazy!