IETs (not) banned through Dawlish during rough seas

Discussion in 'Traction & Rolling Stock' started by irish_rail, 30 Oct 2019.

  1. Grecian 1998

    Grecian 1998 Member

    Messages:
    56
    Joined:
    27 Oct 2019
    Location:
    Bristol
    Starcross isn't Dawlish - it's about 2 miles beyond the seawall and the Exe Estuary is generally very calm due to being a mile wide and shallow in most places. It appears the article's basis for suggesting it failed due to seawater is that one man (who appears to be a passenger) claims he was told it failed due to seawater entering the engines. The article also claims that GWR are investigating the fault.

    Certainly it might have failed due to seawater - but it might be a good idea to wait for GWR to conclude their investigation rather than relying on what one identified man claims a member of staff told him.
     
  2. Bletchleyite

    Bletchleyite Veteran Member

    Messages:
    48,530
    Joined:
    20 Oct 2014
    Location:
    Up and down the south WCML (mostly)
    It's not entirely out of the question that water that hit the train over Dawlish took a couple of miles to drip through to somewhere that caused issues with electrics. Cars that have been driven through deep standing water often break down a short way down the road when exactly this happens.
     
  3. Grecian 1998

    Grecian 1998 Member

    Messages:
    56
    Joined:
    27 Oct 2019
    Location:
    Bristol
    Well indeed, that thought had crossed my mind. I'm not saying this wasn't the cause, just that there isn't enough information yet to conclude this was definitely the problem.
     
  4. The Ham

    The Ham Established Member

    Messages:
    6,878
    Joined:
    6 Jul 2012
    And even if sea water is the cause then it could still have caused other trains to have failed (i.e. IC125's) depending on the circumstances.
     
  5. hexagon789

    hexagon789 Established Member

    Messages:
    7,691
    Joined:
    2 Sep 2016
    Location:
    Glasgow
    Would most trains cope with that or us there something specifically for the salt water?
     
  6. Clarence Yard

    Clarence Yard Member

    Messages:
    1,138
    Joined:
    18 Dec 2014
    It is the salt that causes some of the issues. The units cope with spray but not with the effect of drenching the roof with salty sea water waves.

    A wave hits the brake resistor so the traction converter will detect an earth fault and shut the GU down. The wave subsides so you can restart but the path to earth through the residual salt will still exist so the traction converter will detect an earth fault again, shutting the GU down again and then it is automatically isolated.

    As the roof condition will gradually improve after a wave hit, the idea is to change the GU restart sequence and number of resets allowed (10 is the proposed figure, I believe) but only in a limited geographical area and only when sea waves are expected.
     
  7. fgwrich

    fgwrich Established Member

    Messages:
    5,372
    Joined:
    15 Apr 2009
    Location:
    Between Edinburgh and Exeter
    Exactly as I was told a few months ago, thank you for putting that out in the open. Unfortunately it is a similar problem to that encountered by the Voyagers, so I believe there will also be some modifications to the surroundings of the brake resistors to reduce the impact of the salt water and where it actually goes / where the contact issue is. I do wonder if the flat roof design of the Hitachi Fleet also adds to the problem - At least with a curved design, that water has somewhere to run. With a flat roof, you're really relying on physical dynamics / gravity / the airflow to ensure it reaches the drains to run off from the roof.
     
  8. broadgage

    broadgage Member

    Messages:
    1,059
    Joined:
    11 Aug 2012
    Location:
    Somerset
    I, and others, forecast that the IETs would fail to cope with the adverse conditions found at Dawlish. This was dismissed as "wibble"
    Being able to cope with extreme conditions was an "essential requirement" of the IET specification, and regardless as to the exact details the units have demonstrably failed to cope with the conditions.
    All looking very Voyager like.
     
  9. jimm

    jimm Established Member

    Messages:
    5,043
    Joined:
    6 Apr 2012
    As usual, both here and elsewhere, you overplay your hand with exaggerated claims.

    The requirement for the IEP project was as follows

    A bit of spray being enough to lay low a Voyager, hence the stated requirement in the IEP spec. Which is different from being hit broadside on by waves overtopping the sea wall.

    IEP technical specification, page 24

    https://assets.publishing.service.g...s/attachment_data/file/82840/tts-redacted.pdf

    The 802s have some additional features around the brake resistors on the roof as well, but if the key issue is water getting all over the engines and their electrics at low level, then that will require different solutions.

    There is still clearly a way to go to solve the problem, but trying to replicate the 'Dawlish effect' in a simulation is not exactly straightforward, as Hitachi will have realised by now, after also overplaying their hand a couple of years ago with things they said to the media.
     
  10. northernbelle

    northernbelle Member

    Messages:
    241
    Joined:
    10 Oct 2018
    What on earth makes you think 'GWR' is 'content' with short forms? Far from it. There are, of course, many more booked 5 car workings on the route than pre-December, including the 'semi-fast' B&H workings along with the majority of workings west of Plymouth.


    I have to admit I was somewhat surprised when confident releases about being 'Dawlish proof' appeared - I wouldn't have said that even if I was convinced it were true. Hitachi did carry out specific testing on the 802s with Dawlish in mind and there is a software modification on its way to help improve the situation - it'll be interesting to see if they have any impact.

    The problem is very much due to the salt content of the water - and the inherent electrical conductivity this provides.

    Of course - it might be that the software is doing a good job of protecting the engines from a more serious problem that the salt water would cause - I'd certainly not want my car engine to be exposed to the extremes of Dawlish nor would I want salt water entering the exhaust system of my very expensive MTU 4000 series HST engine.
     
  11. Grumbler

    Grumbler Member

    Messages:
    284
    Joined:
    27 Mar 2015
    They should be exploring an alternative form of proplusion along this stretch. Such as a piston on the rain which fits a tune between the rails causung the train to move when air is pumped through. Should be a winner!
     
  12. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    Well I'm only referring to the fast Plymouth to London services , not the b and h stoppers. Got told by many on here there would be no issues however every single day this week there have been short forms on the fast hourly trains. 1a71 and 1a84 seem two particular favourites despite a84 being a particularly busy train.
    And if GWR weren't content to let it keep happening they'd start sending some extra 9 car sets down this way for the London and Plymouth starters and cancel one of the 4 trains per hour to bristol if necessary.
     
  13. jimm

    jimm Established Member

    Messages:
    5,043
    Joined:
    6 Apr 2012
    Who ever said there would be "no issues"?

    As I have had to remind you and others once or twice, in the good old days there were plenty of occasions when there were no 'issues' on services to the West Country, Bristol or South Wales, because an HST was taken off Oxford or Cotswold Line duties after another HST failed - yes folks, they really did break down sometimes - and these situations led to 'issues' on Oxford/Cotswold runs and on whichever Thames Valley diagram got robbed of a Turbo to plug the gap - but of course that's quite different, because it's just commuter-land.
     
  14. TractiveEffort

    TractiveEffort Member

    Messages:
    290
    Joined:
    29 Nov 2016
    There were a number of units out of service for repairs, that were absolutely nothing to do with train reliability. Two front ends damaged by fatalities, two 5 cars and a 9 car damaged by hitting something near Hullavington and the subsequent ballast strike, the 9 car has suffered a lot of damage from this incident.
     
  15. 83G/84D

    83G/84D Established Member

    Messages:
    4,618
    Joined:
    28 Oct 2011
    Location:
    Cornwall
    Engines (or GU’s) on the up train failed in the Dawlish area but the driver coasted the train clear of the affected area before coming to a stop near Starcross. Meant that another IET could come from Exeter to assist without suffering the same fate.

    Well done driver I say!
     
  16. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    These are all day to day railway occurrences and they will continue to suffer such mishaps so why isn't there enough cover when units are inevitably out of service???
     
  17. pompeyfan

    pompeyfan Established Member

    Messages:
    2,958
    Joined:
    24 Jan 2012
    Because how much slack in the fleet is too much? To have 4 units long term damaged in a week cannot be mitigated against. Do you have 3 extra units? 10? How about a whole extra fleet ‘just in case’
     
  18. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    Well the slack shouldn't be falling on the west country trains. 1a76 gone up to London this morning as 5 vice 10 rammed to the gunwhales off plymouth with military types. My argument is simple. When there is a shortfall it must be the 4 tph to bristol that suffers and not the hourly Plymouth to London trains.
     
  19. samuelmorris

    samuelmorris Established Member

    Messages:
    4,484
    Joined:
    18 Jul 2013
    Location:
    Brentwood, Essex
    In theory I agree, however the strict rules about which diagrams which subclass of unit operates mean that may not always be possible. If there is an 802 shortfall, as far as I'm aware 800s are rarely permitted to cover it. The main purpose of course of such draconian limitations is that there shouldn't be shortfalls to begin with, but there you go.
     
  20. pompeyfan

    pompeyfan Established Member

    Messages:
    2,958
    Joined:
    24 Jan 2012
    I agree to a certain, but there’s very much a attitude of ‘I’m alright jack’
     
  21. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    This is true, but 802 9 car sets tend to be used primarily on none south west routes anyway so my argument is they should be used on the Plymouth route instead of the bristol, I realise 800s won't likely be sent down here....
     
  22. Wilts Wanderer

    Wilts Wanderer Established Member

    Messages:
    1,170
    Joined:
    21 Nov 2016
    Just to point out, the ‘4tph to Bristol’ Irishrail keeps banging on about isn’t actually running yet. Cancelling a Bristol service will result in an hour’s gap on that route. Particularly bad on a Saturday just before Christmas when all the world and his wife seems to want to visit Bath for some reason.

    This is not to understate the demand for Plymouth to London. It just points out (again) the ludicrous fallacy that Bristol trains off peak are somehow fresh air expresses, which is complete BS, these trains are busy.

    Incidentally the 1002 Paddington-Penzance and 1620 Penzance-Paddington, along with the 0815, 0915 and 1015 Penzance-London services on Saturdays are diagrammed a full-length rake, either 9 or 10 car, throughout, due to anticipated loadings all year. This is effectively possible because there is more slack in the fleet on a non-weekday. So don’t accuse GWR of deliberately under-providing the West Country through some sort of vendetta against the Cornish market. Where a need was identified, it has been covered. If there are apparent shortfalls that emerge as the timetable beds in and customer behaviour changes to match the new timetable patterns, it will be dealt with where possible. It’s like buying a tailored suit - until you try it on, you don’t know exactly where it needs adjusting, however accurate the initial measurements were.
     
  23. HowardGWR

    HowardGWR Established Member

    Messages:
    4,837
    Joined:
    30 Jan 2013
    Forgive me but you always write about 'GWR' as though you were talking about it as some separate entity and you always write about it negatively, but AIUI you are an employee of the company. Did I get this last fact wrong?
     
  24. Wilts Wanderer

    Wilts Wanderer Established Member

    Messages:
    1,170
    Joined:
    21 Nov 2016
    Can I politely observe that I’m not sure anyone is obliged to answer that sort of question, however obvious (or not) the answer might be.
     
  25. Clarence Yard

    Clarence Yard Member

    Messages:
    1,138
    Joined:
    18 Dec 2014
    I am really fed up of this mad West of England vs Bristol argument polluting every IET thread. Give it a rest, please. As pointed out elsewhere, GWR doesn’t have free enjoyment over unit deployment, even if wanted to do as has been suggested.

    The real problem is that Hitachi tend to have the spares for each fleet (if they exist on that particular day) at Stoke Gifford and North Pole. What works into Long Rock, Laira or Maliphant gets put back into traffic from those locations the following morning, if it still works. So if you are short in, you will almost certainly be short out. This morning both Laira and Maliphant put out short forms, as a result of misbalances in and overnight stoppers. Short forms are not exclusively on the West of England services, by any means.

    Getting back to the subject of this thread, Dawlish can exacerbate this effect. If you get a stopper at Laira which needs a bit of TLC, you then shortform, usually until you get back to London and if one spare is available there (and their spare availability isn’t usually great) you can get back to booked formation. That is important because if you don’t and the diagram drops at Laira, Maliphant or Long Rock (or an outstation) you are not going to help matters.

    Dawlish seems to affect 5 and 9 cars fairly equally. I am a little sceptical about the proposed fix as the instances of extreme weather along that stretch seems to be increasing and there is only so much you can do when your units are subjected to high pressure salty sea water. It will help a bit but, in my view, a longer term solution for that stretch of line really needs to be seriously considered.
     
  26. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    Maybe I am or maybe I'm a fantasist who likes to pretend. It's hardly relevant other than the fact if I do indeed work for the company, I am there on the ground watching the situation unfold up close and personal. And bearing the brunt of customer angst. And what is wrong with trying to look after the customers who pay my wages (if indeed I am an employee and not a Walter mitty character......)
     
  27. TractiveEffort

    TractiveEffort Member

    Messages:
    290
    Joined:
    29 Nov 2016
    The whole set up is at the heart of the matter, minimal time at outstations overnight, diagrams that keep units in the WC for an extended time, making it difficult to get them back to a main depot if they have a repair that needs doing. The contracts that make use of units across the board nigh on impossible.
    It’s not the staff on the ground or in control, be they GWR or Hitachi that are to blame, they are doing their best to manage a set of contracts that were ill thought out from the off.
     
  28. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    What he said! I do think an actual Hitachi maintenance base in the west would help (tavy yard in Plymouth perhaps)....
     
  29. jimm

    jimm Established Member

    Messages:
    5,043
    Joined:
    6 Apr 2012
    I would have thought train managers and platform staff are rather more likely to be bearing the brunt than the person up in the driving cab.

    Could you explain how the Bristol service (or just about any other bit of GWR's operations that you have told us over the years should be subordinated to the ever so special requirements of Plymouth and Cornwall) is supposed to come to the rescue on a Saturday, when the weekend service between Paddington and Bristol is 2tph?

    Unless something has changed, I am not aware that there is any intention that the 4tph off-peak Bristol service, once fully implemented, will be extended from weekdays to run at weekends.

    Never mind that whatever day of the week it is, there is far more custom between Paddington and Bristol than Paddington and Plymouth.
     
  30. irish_rail

    irish_rail Established Member

    Messages:
    1,263
    Joined:
    30 Oct 2013
    Location:
    Plymouth
    I am not referring especially to Saturday's just that in general, I think it better to knock a bristol on the head making 3tph if it means a full length Penzance to London train.
    And the fact there is more custom on the bristol route is irrelevant. They have 4 times the trains now. But if one of their trains turns up as a 5 car either wait 15 mins for the next one, or put up with just over an hour of standing. On the PZ route the options are wait an hour for the next one or put up with 3 hours + standing!!!! Very different services, Bristol is no longer really intercity, more metro.
     

Share This Page