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Edward Thompson: Wartime C.M.E. Discussion

Discussion in 'Steam Traction' started by S.A.C. Martin, May 2, 2012.

  1. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    I would humbly suggest Fred is probably the closest to the issues here than anyone else has been (myself included) in the last 166 pages of discussion. Yes, the role of the CME I think is monumentally misunderstood to a level that makes a CME far more powerful than he actually is.

    CMEs are not just engineers: they are responsible for systems of systems and for being personally accountable to a board of dirctors. In Gresley and Thompson's case from 1939 to 1945 they were also accountable to the wartime executive. The complications of this together with what needed to be done to support the war effort was incredible. I personally believe that neither Gresley nor Thompson get the recognition they deserve for their work in this way.

    I hope my book can redress that balance somewhat as both CMEs haven't really received that recognition.
     
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  2. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    My apologies, missed this yesterday. I hope to give a balanced viewpoint. There are undoubtedly also-rans in the Thompson loco design stable - the D class and B2s come to mind - but most were more than adequate for the work asked of them and in the B1, K1 and O1 were otherwise excellent designs on paper that actually led to successful locomotives that did the work asked of them.
     
  3. johnofwessex

    johnofwessex Resident of Nat Pres

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    Given that Thompson was long dead by the time all this came out, why fan the flames?
     
  4. huochemi

    huochemi Part of the furniture

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    Hi Simon, Re the Cox report, I don't think you can entirely dismiss the commercial reality that when you commission a report, the employer would want the report writer to know what his conclusions are expected to be, which does not mean the report is dishonest (or the commissioning party's motives were Machiavellian), and in this case I am sure the conclusions were valid within the context. A report is amongst other things a CYA item so executives can point to it if things do not go according to plan.

    On the report itself, which I have not seen, the language in the final sentence in Conclusion 1 of the report (which you helpfully published a few pages back), "In view of [the 2 to 1 valve gear's] inherent defects and the discontinuance of its use throughout the world, a good case can be made..." (the bolded bit) is a bit strange, and arguably misplaced, as it cuts across the logical /forensic arguments and seems to say "well even if you ignore these technical points, other people don't use it" which, while a valid observation put into context, is not necessarily a good or appropriate one in such a document (one might perhaps note it in a preamble as to the terms of the investigation).

    A couple of things, if I may be so impertinent, which I would hope find their way into the final draft, both of which I have raised before:

    1. It would be good to get an understanding of what the emergency board was, e.g. its members and function and its relationship with the main board.
    2. You have emphasised, correctly, that ET was operating under difficult wartime conditions which led to reduced and indifferent maintenance etc. But what did he actually do to ameliorate the maintenance situation (or to put it another way, what did the LNER do, as much if not all of the maintenance function is devolved to sheds and works, and is this something that ET needed to involve himself in)? Based on what has been said on here, one could come away with the impression that ET's solution was to build new locos that would only be available in a few years time.

    Incidentally, Cook on the Great Western found regular boiler maintenance / washouts to be a big problem during the war, because locos were use in a more ad hoc way, exacerbated by staff shortages. Did this issue arise on the LNER?
    Kind regards
    Robin
     
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  5. johnofwessex

    johnofwessex Resident of Nat Pres

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    It seems to me though that '....the discontinuance of its use throughout the world...' is a very relevant observation, ie nobody has managed to make it work/thought it worth continuing with, clearly if it was in widespread use elsewhere the obvious question would be 'so why cant we make it work?'
     
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  6. Fred Kerr

    Fred Kerr Resident of Nat Pres Friend

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    Which brings one back to the basic question of how the operating staff (i.e. motive power department and individual depots) handled the problem. The LNER, it appears, was happy to continue using it knowing that some depots considered the gear troublesome but still obtained acceptable availability for the depot's workload whilst other depots dealt with the problem by amending maintenance and maintenance schedules to suit their specific workload. This factor would be obvious to the LNER Board but - in the exigencies of wartime - there was additional pressure that - possibly - Gresley felt at the beginning of WWII could be accepted in the short term whilst Thomson by the middle of WWII with no discernible end - was forced to deal with in order to meet wartime traffic commitments. I suspect Simon may be able to evaluate that situation from analysis of the maintenance records although I don't expect too much analysis to appear in the proposed book except as a reference in the accompanying bibliography.

    In terms of the situation outside the UK, however, it may also be that the discontinuance was due more to the inability / unwillingness of staff to deal with the "problem" rather than any inherent fault with the design itself.
     
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  7. MarkinDurham

    MarkinDurham Well-Known Member

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    Apologies, Tom. This thread moves on so fast at times.

    Mark
     
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  8. Eightpot

    Eightpot Resident of Nat Pres Friend

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    Do you know if the Peppercorn era K1s had beefier axle boxes compared with B1s and L1s? Perhaps being more involved in freight work the problems didn't arise, but I must say that I cannot recall seeing or reading anything detrimental about them as regards the axle boxes.
     
  9. bluetrain

    bluetrain Well-Known Member

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    Tom -

    Some interesting historical reflections in your post. Where a new boss introduces major changes, they sometimes end when the next new boss arrives, but sometimes endure. The Great Eastern had a succession of loco superintendents with widely differing ideas before the long reign of James Holden brought stability and standardization. Meanwhile in Scotland, Dugald Drummond stamped his marque so firmly on both the North British and the Caledonian that his successors followed and developed his ideas until Grouping.

    As you indicate, Thompson was unable to fully "sell" his changes. While there is no doubt that he was a competent engineer and administrator, he seems to have lacked diplomatic and political skills. Gresley on the other hand possessed such skills, perhaps best shown by the way he was able to draw together and consolidate his large department during the 1920s, without the LNER suffering the degree of friction that afflicted the LMS during that period.

    Simon Martin's research is indicating that the main drivers for Thompson's loco design changes were to ease maintenance and improve availability, driven on by poor availability levels of LNER locos during WW2. Under war conditions, statistics on breakdowns and availability are likely to have been classified information, to be shared only on a "need to know" basis. If so, that may have constrained Thompson's ability to fully explain to LNER staff, or to the engineering community, the reasons behind his loco rebuilding projects. If staff were unaware that the P2s had suffered serious mechanical issues including several crank axle failures, and that their availability had nose-dived under war conditions, then they are likely to have found the P2 rebuilding inexplicable and been baffled by the idea that the A2/2 was an improvement. If moreover, Thompson had made some staffing changes that had led to resentment, it is easy to see how the idea gained traction that Thompson's rebuilding projects were simply aimed to "spite Gresley". Conspiracy theories are not new.

    Even a commentator as well-informed as ES Cox seemed confused and ambivalent about Thompson. Cox wrote ("World Steam in 20th Century") that "Thompson did what had been a commonplace with the old autocratic CMEs of pre-1923, namely completely reversed the Gresley line of development....... The conjugated valve gear for three cylinders was, however, replaced by three independent gears, and two instead of three cylinders were applied to all the smaller types. Although Thompson has been much criticised, what he did in these respects was technically right and in keeping with world trends."

    As things turned out, the fruits of Edward Thompson's changes were mostly seen only after his retirement, as large numbers of new locomotives (mostly B1s) and carriages were built to his designs. Although Peppercorn modified Thompson's pacific designs, Thompson's developments did largely endure.
     
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  10. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    I think you make good points here, but the discontinuance of an engineering approach elsewhere in the world is relevant.

    Engineering trends rarely keep inefficient working, it is definitely a “survival of the fittest” approach, otherwise we would still be using steam locomotives and not electric ones today, or for other analogies, paddle boats instead of propellers, petrol cars instead of electric cars…!

    Discontinuance elsewhere will influence. Betamax vs VHS. Cassette vs disc vs digital download.

    (Yes I am aware in the latter case, some of these are making a comeback and also vinyl, but it’s more niche and definitely not mainstream!)

    You make a good point.

    A normal LNER board meeting would consist of the directors and the LNER’s chief (variously Sir Ralph Wedgwood, William Whitelaw and Charles Newton), plus the CME on occasion where required (Both Gresley and Thompson liked attending these, even if they did not necessarily contribute to discussion. Where Gresley was unable to attend, either one from Bulleid, Thompson or Peppercorn would go in his stead. When he was ill in 1941, Thompson was asked to represent Gresley on occasion. Peppercorn also attended as Thompson’s deputy at these meetings).

    The Emergency Board was formed from the LNER’s board of directors, and this replaced the normal board meetings by way of including in its meetings where necessary any interested parties such as members of the wartime executive, CMEs of the company plus assistants (mech and electric, from 1941), heads of and superintendents across the various regions of the LNER, and various other invited parties to report back on projects (such as classified work for the MOD), infrastructure, policy decisions, finance and similar.

    Emergency board meetings worked the same as the normal LNER board of meetings, even happening on roughly the same dates each month.

    Additional points to consider were obituaries (in wartime, monthly updates and commemoration on any staff or important personnel to the UK lost were recorded), confidential work for the MOD and policy decisions which were taken by the board, with people advising on the specifics.

    So, using the locomotive policy as an example, the board asked Thompson in June 1941 if he intended to continue in Gresley’s vein. Thompson declined, as he felt that the issues of availability were such that Gresley had been considering changes too, and he felt that he should make more wholesale changes.

    He recommended a change in approaches to maintenance and engineering. The recorded board response was that they would like to see – where the engineering was considered – a report on the current state, to enact a new policy going forward, which Thompson agreed with.

    The board voted on allowing changes to policy for the CME where maintenance was concerned and for Thompson to return to the board with a report from an independent engineer to assess what to do next.


    In the interim, it was agreed that – given the restrictions of the wartime executive in new builds – that some conversions of existing were to be approved, with as far as practicably possible, existing components or tooling used. This led to the Q1s and B1s, effectively.

    Bear in mind that I am still working through a lot of material, but the whole approach was complex as the situation was complex.

    The problem was availability. Low availability for a class is caused by:

    • Engines stopped awaiting work at sheds and workshops

    • Engines waiting on boiler washouts

    • Engines being worked on at workshops

    • Unexpected failures
    The solutions which were carried out were to change policies on certain things. For example, Gresley and Thompson relayed direct instructions to all of the major works for things such as:

    • Limit mileage of conjugated locomotives and explicitly undertake greasing of internal gear at set periods (Gresley)

    • Boiler inspectors to carry out detailed examinations of any locomotives prior to shopping. If boiler in acceptable condition, order a return for the locomotive to traffic

    • Where possible, ensure adequate spares for certain components at sheds to avoid necessity for shopping to major works
    We are talking about a nationwide urgency for availability of locomotives. There was a class of engines, the J25s, which were overhauled for use on the GWR, for which a number were held back by Thompson for a short period as the LNER was experiencing very difficult time in availability.

    Yes, and as above certain policies were put in place to try and reduce time lost to this.

    Agree to a certain extent. The trouble isn’t so much – in my view anyway – that it couldn’t be made to work – it had done pre-war – but there was absolutely no guarantee of a return to pre-war conditions for staff numbers, availability of materials and similar. None at all.

    Thompson was designing for a future world where he (and everything else) wasn’t sure if the nation was under British rule or not (!) – and if it was, what kind of world was it going to be like?

    I think it is this context which is incredibly important. The stress levels of the LNER’s design team and its workers must have been far in advance of anything we see today. No one could plan for five years time let alone ten years’ time as there was just no way of seeing an end to the war, particularly in 1941 and 1942.

    I have bolded this as I think this underlines exactly what I have been talking about and trying to get across for nearly seven years.

    That is – partially – true. The Cox Report and the discussions around it were classified, as all the emergency board minutes were, during the war and for some time afterwards.

    The problem with the P2s is that it was an open secret they were struggling during the war, if not obvious. By 1942, availability was barely half of their time in traffic and their mileages were dreadful.

    The internal availability figures document does not look to have been confidential, at least in the LNER internally, as far as I can work out, so from Scotland to London you would have been able to get an idea of how good or bad they were doing.

    Unless someone is suggesting Thompson gerrymandered the figures for the P2s deliberately (surely nobody is suggesting that, I hope?) then you kind of have to take that on the chin and accept the P2s were not particularly good and especially during the war.

    People keep on banging on about the opportunity to “send them south” – and I ask again – if you are a shedmaster in England and you get told about these high-power machines, which have suffered crank axle failures, overheating axleboxes and some slow speed derailments in yards, would you:

    • Take them on

      (or)

    • Refuse them politely

    I’m not convinced it was ever a choice to bring the P2s south. At least on their original route, the speeds required were lower than that on the ECML.

    I am not saying the P2s were dangerous…but when you consider Bibby Line’s crank axle failure at speed, and the withdrawal for examination of the MNs post war by comparison, one could ask whether Gresley and Thompson should have withdrawn the P2s, instead of Thompson rebuilding them.

    Harsh, maybe? I think it’s worth asking the question.

    I think you may be correct in the staffing question regarding Thompson. To me, it seems that if there was indignation at rebuilding the P2s internally, it was after the event, not at the time. Thane of Fife went from being one of the LNER’s worst individual locomotives for availability to one of its best in one calendar year.

    The report to the emergency board – not made by Thompson but by Peppercorn, who had observed the rebuilt locomotive on trial in Scotland over the course of a year – was that the rebuilt locomotive was exceeding expectations. Off the back of that report, the rest were to be rebuilt.

    What bothers me most about Cox is that he was his own man and he was perfectly capable of turning around to Thompson with his report with different suggestions and solutions.

    He puts a lot of emphasis on Thompson’s decision making some time after the event – perhaps knowing that his report was not likely to be published – but it was he who had written it, with Stanier’s approval.

    I would also challenge the “completely reversed the Gresley line of development” and describe it politely as not in line with the facts.
    • Thompson kept all Gresley’s major classes with only one exception running – the P2s

    • Continued development of locomotives using parallel boilers – see B1s etc

    • Continued using Gresley era components and developments thereof
    The only change made was three to two cylinders for small and medium locos – it is not as if everything Gresley built were three cylinders, he also built a number of two cylinder machines as well – Thompson even asked for a further batch of Gresley J50s.

    The coaching stock Thompson had designed was – factually – different from Gresley’s and it had to be. Gresley coaching stock, though pretty, had its own issues. You could argue reasonably that LNER coaching stock lagged behind other railways (LMS in particular – looking at Stanier porthole stock) on some things, but on other things was far ahead (articulated trains in fixed formations).

    Absolutely agree.

    From my notes, the axleboxes were the same as the L1s. I suspect the tanks were the problem – if they leaked, water ingress would have likely caused problems. However that is speculative and there are also some notes from a variety of writers that it was the fact the axle boxes were not castings but fabricated that was the issue, with shims fitted to fix issues in their later years.

    If they were so terrible, one suspects in the 50s there would have been a move to re-design this or fit a standard component but seemingly not.
     
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  11. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    Nail - head - hit.

    Not sure. It is notable that the only other railway to use it rebuild its conjugated gear fleet (as Tom has alluded to a number of times, with my apologies for forgetting which of the Holcroft engines it was). In Thompson's case I think you could say the inability of staff to maintain it due to a lack of trained staff and a lack of staff generally would be more likely.

    But the Cox report sets its stall out quite strongly and if Thompson was already thinking along those lines, then the report justifies the path he took as a result - which is not the same as having a report made to force his ideas through. Gresley had recognised availability was a problem but was unable to deal with it prior to his death, for a variety of reasons - Thompson then was left with not a lot of room to maneuverer I feel. If he does nothing, the problems remain. If he does only small changes, would it be enough? If he removes the gear entirely, it ceases to be a problem in future. To me that seems logical.
     
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  12. 30567

    30567 Part of the furniture Friend

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    Just on one point, the possibility of transferring the P2s south, Townend says

    ' The P2s occasionally worked over the GN main line from KX, but their regular use would have caused some difficulty from this point of view as there were a number of tight curves in the KX station and depot area.'

    So probably the only realistic option would have been to transfer them to Heaton or Gateshead to work to/from Edinburgh and Grantham. If they had had good annual mileages, maybe that's what would have happened. Townend concludes the section on the P2s by saying

    ' Under wartime conditions, it is not surprising that the new CME should select the P2s for rebuilding into a prototype 6' 2'' wheel standard Pacific, although sadly by doing so, he defeated the very purpose of the P2 design ie high tractive effort with the increased adhesion of an eight coupled locomotive.'
     
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  13. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    I wonder how likely still - Gateshead was certainly not short on Pacifics which were proving more reliable.

    Which is a fair point - my rebuttal would be that the W1 was on test on the same trains as the P2s, and then the lone A2/2 was found adequate as well. The advantages of a Mikado versus a Pacific don't seem to translate if it's only available half the time.
     
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  14. huochemi

    huochemi Part of the furniture

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    Hi Simon, thank you. Re the discontinuance of Gresley gear, you misunderstand my point. It could be relevant but not in that particular conclusion.

    Knowing your keenness on dissecting remarks in the written word, in the same vein one could challenge the use of "discontinuance". Gresley gear is obviously only applicable to three cylinder locos, and the use of three cylinder locos globally was not that extensive. Of those, some did not have Gresley gear ab initio (so, strictly, not discontinued although one suspects this may have counted in Cox' view e.g. the LMS doesn't use it), and of those that were fitted with it, some will have been on locos where there was no further requirement for additional locos of the same type, and some will have been on locos where the generally greater maintenance requirements of multi-cylindered locos was the key determinant to future orders e.g. they were replaced by two cylinder machines (the Britannias are an example).

    I suspect pure "discontinuance" (which effectively requires the Gresley gear to be removed from a later order of the same type of loco, but one could also factor in any later order for three cylinder locos, as with an LNER-type change of policy) was limited. The Thai Baldwin Pacifics (where the later batch did not use Gresley gear) would qualify, but even assuming Cox knew about these, he would hardly extrapolate from that example. There may be others, you may have some examples.

    In hindsight, it seems surprising that the report focused on the Gresley conjugated gear, as the more fundamental trend, even in the rather idiosyncratic world of British loco design (and fundamental mechanical change for the B1 vs Gresley's mixed traffic designs) was the use of two rather than three cylinders.

    Kind regards
    Robin
     
  15. 30567

    30567 Part of the furniture Friend

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    Absolutely. Townend's ch in EC Pacifics at Work seems close to your analysis.

    My point was, suppose the P2s had been just as reliable as the A3s/A4s apart from specific issues traceable to the curvature etc on the Aberdeen road, then maybe swapping the P2s for the A4s between Gateshead and Haymarket may have made sense. But that was not the situation.
     
  16. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    Hi Robin - and I think you would be entirely correct, were it not for the fact that it seems that within the overall trend of poor availability for the LNER fleet, the Gresley conjugated engines, specifically, were around 10-15% lower compared to similarly aged 2-cylinder engines. The best comparison is probably the small class of K4s versus the larger groups of K2s. Here's some stats for 1942 showing this example:

    upload_2019-9-9_15-3-6.png

    It is clear - to me anyway, as I have the stats in front of me - that the conjugated engines suffered the most during WW2. We're not just talking the Pacifics, we're talking the tank engines, 2-6-0s, 4-6-0s, 2-8-0s and the unique ones too.

    The report focused on these as these were the ones with the worst overall availability.

    There were no three cylinders on the LNER designed by Gresley that didn't use conjugated valve gear so the fact the onus was on these is unsurprising.

    I think Townend has probably been the fairest writer on the whole thing, especially where the Pacifics are concerned.
     
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  17. huochemi

    huochemi Part of the furniture

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    Hi Simon, thanks. I would turn that on its head and say that comparing a three cylinder loco against a two cylinder loco is not comparing like with like. The additional cylinder (and inside valve gear) is likely to cause problems in a poor maintenance regime whatever the valve gear so I would be very nervous at extrapolating that to say that the problem is Gresley gear, replacing it with an independent set of inside valve gear will resolve the problem. The issue of why maintaining Gresley gear is so difficult versus maintaining more-difficult-to-get-at inside valve gear has been raised on here before without satisfactory resolution. I would say that the stats support a switch to two cylinder locos, not three sets of independent gear.
    Kind regards
    Robin
     
  18. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    Robin, I think you are actually misunderstanding the report's conclusions. It said that the basic solutions were:
    • Do not build any more locos with conjugated valve gear - Thompson did that
    • Convert some of the larger classes with a third set of walschaerts possibly - Thompson did that with B16/3, and the Pacifics
    • Or use two cylinders - Thompson did that to a range of conjugated classes and all new classes were two cylinder
    The K2 and K4 are classes of similar size and tractive effort, and the disparity in their availability is noticeable. That was the comparison being made.

    The further point is that in the K4 case, they didn't fit a third set of walschaerts valve gear but converted one of them to two cylinders to create K1/1. They removed the conjugated gear completely.

    Hi Robin - that's exactly what Thompson did for all small and medium sized locomotives. The only exception in that category being B16/3, which had three independent sets of valve gear, and all the Pacifics, of course.

    I would argue that Thompson was not shown to be entirely wrong in his thinking on the larger engines - born out by the Peppercorn A1s and A2s and the rebuilt Bulleid Pacifics which all followed Thompson's lead largely.
     
  19. huochemi

    huochemi Part of the furniture

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    Quite possibly as I have not seen it other than the conclusions, but I do not set as much store by the report as you, as to my mind, Cox would have known what the report was supposed to say before he wrote it. To suggest that because availability of three cylinder locos is worse than two cylinder the valve gear is to blame seems a bit of a hiatus in logic, and suggests to me an agenda. Having been a Thompson supporter, I am afraid I am becoming sympathetic to the commonly held view as to ET's attitude to Gresley (which is not to denigrate ET's work as an engineer, and I appreciate that in fact there was much of Gresley's design that he retained). Somehow, this Dilbert strip comes to mind.;)

    dilbert.gif


    As I put in my post, the rather more obvious conclusion would be to ditch three cylinders in favour of two (which also tackles the inside big end issue). This does not seem to be in the three conclusions you posted on p163, but perhaps it comes through in the body of the report? I agree the loading gauge may cause difficulty if you want the oomph from just two cylinders (coupled to big wheels), and UK loco design was not then quite ready to embrace the concept of a big two cylinder express loco.
     
    35B and 2392 like this.
  20. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    I mean Robin, if you haven’t read it in full, how can you draw those conclusions? Just wondering!

    What was the point of me posting it on this thread again? :Banghead:
     

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