If you register, you can do a lot more. And become an active part of our growing community. You'll have access to hidden forums, and enjoy the ability of replying and starting conversations.

Ton up Tornado

Discussion in 'Steam Traction' started by MarkinDurham, Apr 12, 2017.

  1. gricerdon

    gricerdon Active Member

    Joined:
    Jul 21, 2013
    Messages:
    1,201
    Likes Received:
    461
    Gender:
    Male
    Occupation:
    gricer
    Location:
    near to Wallers Ash
    Oh yes the Bulleid pacifics at 100 mph were very smooth. Ask my brother about 35003 at 106 mph and I can confirm that 34006 and 34026 at 95 mph were as good as being in the trains.

    Not sure why the hammer blow should be worse with older locos but ask NR about the 67s and 68s!!!

    The ton with Tornado was quite superb and should not be under rated. All I would say is look at the historical context and how hard the engine had to be worked to achieve what the run down Bulleids did 50 years ago
     
  2. JJG Koopmans

    JJG Koopmans Member

    Joined:
    Nov 12, 2014
    Messages:
    267
    Likes Received:
    232
    Gender:
    Male
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Travelling today I had some tome to think this over. Hammerblow is basically vertical and, as far as I know, the cracks are in the corners of the cut-outs of the horns.
    My limited knowledge would suggest that that is due to horizontal "beating" within the horns. Of course I bow to better information.
    Kind regards
    Jos Koopmans
     
    Tom2521 likes this.
  3. sleepermonster

    sleepermonster Member

    Joined:
    Jun 19, 2007
    Messages:
    565
    Likes Received:
    178
    I do wonder whether Tornado had a dead diesel hung on the back in these trials and if so, what would have happened without it. I also wonder what might happen when the P2 newbuild is unleashed.
     
  4. gricerdon

    gricerdon Active Member

    Joined:
    Jul 21, 2013
    Messages:
    1,201
    Likes Received:
    461
    Gender:
    Male
    Occupation:
    gricer
    Location:
    near to Wallers Ash
    The DL was removed for the south bound section which included the 100 mph. Load was 9 for about 315 tons
     
  5. S.A.C. Martin

    S.A.C. Martin Well-Known Member

    Joined:
    Aug 31, 2010
    Messages:
    2,202
    Likes Received:
    1,580
    Gender:
    Male
    Occupation:
    Children's Author, Railway Writer, Film Maker
    Location:
    Sidcup, Kent
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Absolutely.

    I would not say Tornado was particularly hard worked: the firemen were worked hard by the 50 square foot grate no doubt and that is something which has been commented on.

    An interesting pair of contrary comments there.
     
    John Stewart likes this.
  6. MarkinDurham

    MarkinDurham Well-Known Member

    Joined:
    May 4, 2007
    Messages:
    1,689
    Likes Received:
    421
    Location:
    Durham
    I believe that, during steam days, about 50 square feet of grate was reckoned to be about the limit for one fireman to cope with for extended periods? This was. of course, when firemen were doing the job on pretty much a daily basis. So the continuous power output limits on locomotives were sometimes more to do with the 'human component' rather than mechanical ones, particularly on larger locomotives like Pacifics.
     
    Jamessquared likes this.
  7. The Green Howards

    The Green Howards Part of the furniture

    Joined:
    Feb 20, 2016
    Messages:
    3,682
    Likes Received:
    1,356
    Occupation:
    Layabout
    Location:
    Your nightmares
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Well, it won't be doing 90 - the P2 team have already said so.
     
  8. MarkinDurham

    MarkinDurham Well-Known Member

    Joined:
    May 4, 2007
    Messages:
    1,689
    Likes Received:
    421
    Location:
    Durham
    Where the P2 will (hopefully) score heavily in pathing considerations will be in better acceleration to line speed/maximum permitted speed with a heavy load than many other steam locomotives are capable of. At her present rate of progress, it won't be too long before we find out for certain :)
     
    Last edited: Apr 16, 2017
  9. 8126

    8126 Member

    Joined:
    Mar 17, 2014
    Messages:
    486
    Likes Received:
    324
    Gender:
    Male
    Hammer blow is inherently a trade-off - it is created by adding balance weights to counter the horizontal imbalance caused by the reciprocating masses (pistons, crossheads, a portion of the connecting rod)*. Because the balance weights are moving in a rotating fashion, while they're not balancing reciprocating forces in the horizontal plane they're putting whole new forces into the track in the vertical plane. To avoid breaking too many bridges, only a percentage of the reciprocating mass was typically balanced, I've seen anything between 40% and 66% referenced for two cylinder engines. So there is still an imbalanced horizontal component applying cyclic stresses to the frames, which goes up with the square of speed (7.1 tons for a Britannia at 90). Smaller than the maximum piston thrusts, of course, but not an insignificant addition.

    Even before imbalance is considered, the forces experienced still go up with speed. So although coupling rods are fully balanced, they still experience an increase in bending stress at the centre and support reactions at the bearings.

    The slightly veiled reference to hammer blow for some class 7 locos in my original post was really referencing the Britannias, as the only two cylinder engines in the 7P/8P bracket. Inherently, they will have worse full-loco hammer blow than any of the others. Having said that, with the honourable exception of the Bulleids, all the three and four cylinder classes tended to have significant single-rail hammer blow because the individual cylinders were still given reciprocating balance, just that the total for the full loco was much less than a two cylinder class. The Royal Scots put greater forces into a single rail than the Britannias did. This is more perhaps something that will concern NR than the loco owners.

    There's an excellent piece out there somewhere on the web by J.M. Jarvis entitled "The balancing of the BR Class 9 2-10-0 locomotives" which explains the whole business of locomotive balancing in British and North American practice very well, with examples that I've extrapolated some of the figures above from.

    * This is separate to any effects due to high unsprung weight at speed, as experienced with several diesel and electric classes, although I doubt steam comes out too well on that count either.
     
  10. Where's Mazeppa?

    Where's Mazeppa? Member

    Joined:
    Aug 7, 2013
    Messages:
    307
    Likes Received:
    213
    Gender:
    Male
    A propos nothing in particular, but thinking about the power outputs and speed exploits of the A1 Class on the ECML in the 1950’s and 60’s, it’s interesting to reflect that it has taken just 51 years, three months, and two weeks to climb the threshold and make up the one or two miles per hour that gets the A1 Class from 60145 St Mungo’s recorded speed of “98/ 99” mph on 31st December 1965** to 60163 Tornado’s ton on the 12th April 2017.

    I gather that the location of Tornado’s 100 mph achievement was somewhere in the vicinity of Thirsk on the Darlington-York racing ground. Likewise St Mungo, somewhere around MP9 south of Tollerton. So both were on level track, while Tornado’s load, quoted by Gricer Don, I think, at an estimated 9 for 315 tons gross, was just marginally in excess of the Load 8 for 290 tons gross of St Mungo’s 1965 run. So the challenge for the human component of power output, with fifty square feet of grate area to feed and all that implies, was pretty much identical. The only difference being that it was a solo effort “on the shovel” throughout with St Mungo.

    Perhaps these runs give some idea of what the class would be capable of, at one point on the load/ speed spectrum, on a sustained basis and on level track – data that may be less spectacular but possibly more informative than the records of umpteen runs down Stoke Bank.

    The references to, and comparison with late-days MN performance, however much of a digression they might be, are interesting, and thankfully respectful considering the focus of this thread. Just one theory to contribute about any perceptions of MN supremacy that may exist in this regard, and I would advance this theory on a strictly non-partisan basis (honestly!!) in the interests of balance.

    Looking at the quantity of archive records that exist to chronicle the performances of the respective locomotive classes, there are almost four times as many logs of the 30-strong class of MN’s in the RPS database as there are of the c.1100 runs featuring the 49-strong A1 locomotive class. Just an observation, but it does tend to suggest that the aura surrounding the performance exploits of Southern Pacifics was as much to do with intensity of observation by the train-timing fraternity of the day, to achieve the number and frequency of recorded high speed runs that were published/ publicised, as it was to do with real and tangible differences in performance capability between the two locomotive classes, which I don’t believe really existed to any significant degree.

    A1SLT did originally plan to run a 50th anniversary commemorative of St Mungo’s run on New Year’s Eve, 2015. Sadly, it was canned in response to slow bookings and amidst fears for the viability of the outing. Perhaps now the Trust will revive this outing for a seasonal bash somewhere between Christmas and New Year this year. I’m sure that it would now get the kind of support that was lacking previously, particularly if, say, it became the event that raised the curtain on regular 90 mph running by Tornado on the ECML. Just a thought!!

    (** Railway Observer June 1966)
     
    Last edited: Apr 18, 2017
    rule55, S.A.C. Martin and 35B like this.
  11. Courier

    Courier New Member

    Joined:
    Dec 1, 2010
    Messages:
    175
    Likes Received:
    90
    Didn't Pommern do 102mph?
     
  12. Where's Mazeppa?

    Where's Mazeppa? Member

    Joined:
    Aug 7, 2013
    Messages:
    307
    Likes Received:
    213
    Gender:
    Male
    Looking back through RPS database logs of 60133's runs, I can't find anything to substantiate a claim for a three figure Vmax for this locomotive. I have traced three separate instances where a maximum speed of 91 mph was recorded, and one of 90 mph - all runs in the down direction, all on the Hitchin-Huntingdon section. Doesn't mean it didn't happen, just that maybe I need to look harder and/ or in a different place. Any idea of the source of this claim? Or approximate date? Or location?
     
    Last edited: Apr 18, 2017
  13. Big Al

    Big Al Resident of Nat Pres Staff Member Moderator Friend

    Joined:
    May 30, 2009
    Messages:
    10,453
    Likes Received:
    6,477
    Location:
    1016
    Heritage Railway Volunteer:
    No I do not currently volunteer
    I am pretty certain that you are correct about the intensity point. And don't let's forget that on the SWML there was a group of enthusiasts who were on the case of all the loco turns that particular crews were working and providing them with a little 'encouragement', shall we say. So the context is entirely different from what was happening on the ECML.

    All we know is that Network Rail gave permission for the test run - remarkable. There were clearly a number of safety related matters that had to be dealt with such as the planned full service brake applications near Thirsk and south of York - necessary. There was also the extensive monitoring, and not just of speed, such as the live sensing of middle big end temperature - sensible. Given all that and the limited windows of opportunity for carrying out the test, it all went well, as far as we can tell, and the ton was also achieved.

    Anyway, although it's great that Tornado achieved 100, I thought the whole point of this test was to assess whether 90 mph running with this locomotive could be achieved within the safety and other constraints of the big Railway. The 'overspeed' to 100 was simply to see whether there was a margin and whether 90 was the absolute limit for the locomotive, which clearly it isn't. We all knew that anyway because of the track record (sorry about that!) of the class but it was still necessary to check. In my view, comparisons with other locomotives are perhaps understandable but rather unnecessary and shouldn't be overplayed.
     
  14. ragl

    ragl Well-Known Member

    Joined:
    Feb 3, 2010
    Messages:
    1,550
    Likes Received:
    616
    Gender:
    Male
    Occupation:
    Consultant Engineer
    Location:
    Shropshire
    See post#65.

    Cheers,

    Alan
     
  15. Courier

    Courier New Member

    Joined:
    Dec 1, 2010
    Messages:
    175
    Likes Received:
    90
    This is the best I can find. These are from "East Coast Pacifics at Work" and "Speed Records on Britain's Railways".

    P1040049.JPG P1040050.JPG
     
  16. S.A.C. Martin

    S.A.C. Martin Well-Known Member

    Joined:
    Aug 31, 2010
    Messages:
    2,202
    Likes Received:
    1,580
    Gender:
    Male
    Occupation:
    Children's Author, Railway Writer, Film Maker
    Location:
    Sidcup, Kent
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Interesting that the smaller wheeled Peppercorn A2 matches the A1 for top speed. They did have pretty much identical boilers (which were also interchangeable with the similar Thompson boilers) all with the same 50 square grate. The 6ft 2in Pacifics were always classed by the LNER as being mixed traffic: an argument that appears somewhat spurious given their obvious capacity for speed.
     
  17. Spamcan81

    Spamcan81 Nat Pres stalwart

    Joined:
    Aug 25, 2007
    Messages:
    25,499
    Likes Received:
    8,419
    Occupation:
    Training moles
    Location:
    The back of beyond
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Somebody doesn't know their A2 names. 60526 was Sugar Palm, not Sugar Plum. :)
     
    S.A.C. Martin likes this.
  18. S.A.C. Martin

    S.A.C. Martin Well-Known Member

    Joined:
    Aug 31, 2010
    Messages:
    2,202
    Likes Received:
    1,580
    Gender:
    Male
    Occupation:
    Children's Author, Railway Writer, Film Maker
    Location:
    Sidcup, Kent
    Heritage Railway Volunteer:
    Yes I am an active volunteer
    Good spot that!
     
  19. Jamessquared

    Jamessquared Resident of Nat Pres

    Joined:
    Mar 8, 2008
    Messages:
    12,523
    Likes Received:
    12,592
    Location:
    21C102
    Fairy 'nuff...

    Tom
     
    Peter Wilde likes this.
  20. Big Al

    Big Al Resident of Nat Pres Staff Member Moderator Friend

    Joined:
    May 30, 2009
    Messages:
    10,453
    Likes Received:
    6,477
    Location:
    1016
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Deliberate. Just in case that performance was a fairy tale........
     

Share This Page