Flying Scotsman single chimney poll

Thanks for your update Anthony it's good to hear that the "curatorial desire" is to have it in the single chimney form but why would you need to redraft it - when it was a regular performer out of steamtown way back when ,I can't remember any of the BR crews ( nor George H) stating it being a shy steamer so why is all this froth stating the need for these "improvements"?

 

The "drifting smoke" issue which keeps cropping up has had me curious for a few years now.

The A1 Trust originally fitted to Tornado a plain stovepipe ala the original A1s. This was removed in favour of a fully lipped version when the livery was first changed to BR dark green, and amongst the main reason for recreating the look of a late BR condition A1, there were those who stated that the plain stovepipe was not as good as the lipped version at reducing the amount of drifting smoke.

Notes I have from Thompson's time (he was the one who originally fitted this type to Humorist and later his own Pacifics) stated that the plain stovepipe was better than a lipped chimney at preventing drifting smoke in combination with smoke deflectors.

Peppercorn then used the same type on his A1 and A2 Pacifics, the lipped chimney type only becoming prevalent in the mid to late 50s and by the end of steam the plain stovepipe was still to be seen on a number of Thompson and Peppercorn Pacifics, but not on Gresley's A3s which without exception it looks like, had the later lipped chimney. It does perhaps beg the question if the difference between the stovepipe and the lipped is negligible, but then members of the A1 Trust have stated their experience with Tornado is that this is not the case.

I wonder what the solution will be ultimately for P2 no.2007 - it'll have a double chimney setup not dissimilar to Scotsman's and Tornado's with a shape which was considered adequate for P2 no.2001 but not for no.2002.

 

Scotsman hasn't been seen on the mainline in anything other than LNER green in preservation, it's nice to have a chance to see her in BR green with all the embellishments now. I suspect that one day she will go back to a more 'original' configuration which will give the chance to see her in various different guises but the chance to see her with double chimney and deflectors will be lost and bearing in mind the NRM's position on originality will likely not come again - so lets enjoy her as such now.

Remember, if the NRM follows it's own rules on originality (as I understand them) then to go back to LNER green as 4472 will require her to be retro converted to an A1 - she was one of the last to become an A3 (and one of the few to be designated A10) - prior to preservation there was no such thing as A3 No. 4472!

 

I don't do froth - just ideas, and saw it often perform well on the Shakespeares in single chimney form, but with indifferent coal these days, if someone is offering to look at the front end for us, I won't turn them down. Some of the Talyllyn, Welshpool and other narrow gauge engines have been looked at and improved upon considerably, and the team are also lined up to work on another main line steam loco before they get to the A3. So far, it will be about measurements, experiments, calculations that I don't understand and recommendations on paper. The NRM is a froth free zone.

 

Probably one of the most sensible points that has been made amid all this froth! As I said in the other 4472 thread, I was surprised that the NRM decided to go for Brunswick green straight away. But I've always suspected the NRM would want to turn her out as 60103 sooner or later, and I've long felt that when the time came, the increased popularity of social media would make a "re-branding" exercise much easier than it might previously have been. The museum always needs interesting material for its Facebook and Twitter feeds - a series of posts explaining the change, posting comparative pictures of 4472 and 60103, and (eventually) showing work in progress on applying the new paint, should fit the bill nicely.

Also, everyone seems to be forgetting that Scotsman appeared in wartime black at her abortive "re-launch" a few years ago, and as far as I could see Joe Public never batted an eyelid!

As I said in the other thread, I do have a personal aspiration to see her return to apple green for her centenary, and I'll go on record and say that I'd be willing to chip in to make that happen. I'd also love to see her in BR blue at some point. Perhaps the photo-charter movement could be a potential source of funding for future repaints? Just a thought.

Anyway, I can't stress enough that the most important things are a.) that she survives at all; b.) that she is still in this country; and c.) that the NRM is committed to getting her back in steam!

 

We're a rather fickle community at times. 4472 doesn't need single chimney to wear LNER colours and be authentic. History didn't end in 1968, and she wore LNER colours with double chimney for a good number of years under Marchington. May not have been her most successful period of operation, but it's still a part of her history and just as authentic as her 1920s LNER condition.

 

46118 hit the nail on the head precisely re draughting and the smoke deflectors - they were required as a result of the softer kylchap draughting.

there is no reason these days why a single chimney should not be re-fitted (apart from cost) and remove the hideous smoke deflectors, and still achieve optimum draughting plus avoid smoke obscuring the driver's view of signals. thanks to some very clever experts a lot more is known about improving draughting than was known in the 1950s and 1960s.

if the above statement can be accepted as an engineering fact then we might achieve something!

incidentally, and in reply to SAC Martin, it isnt the external detail of the chimney that matters (which is pretty much purely a matter of aesthetics) but the internal shape, taper, length and diameter of same plus the petticoat pipe when married up to the blast nozzle/s (Anthony will understand my reference to the plural)

cheers,
julian

 

Would love to see it steamed on its 100th birthday, in 1923 condition,then 'stuffed and mountd' -regardless how much it's loved, it's always being a white elephant. Think of the rest of the nrm and the damage it does spending its entire budget on one machine.

 

Its not being funded from the NRM's budget. No overhaul/restoration has been undertaken from the NRM's budget- certainly not for a while. Everything that has steamed in the last 20 years or so has done so as a result of one form of fundraising or another (benefactors or general appeals) for each specific project. From what I understand, the restoration of 60103 is slightly different, although it is being funded directly by the SMG, which was presumably why engineering consultants were brought into the process a couple of years ago, possibly to assess whether in the light of events the job was too big to be tackled by the NRM in-house and would have to be contracted out. However, this is supposition, though.

 

Definitely a NO for me on this one. We have plenty of archive footage of 4472 in single chimney form operating on the network, and no doubt a lot of personal memories as well. We now have to consider how 60103 will need to perform on today's modern network. As I understand it, the decision to revert back to a genuine A3 boiler will already mean a lower maximum pressure, so why hinder performance even more with a single chimney ? As for the livery, I for one am looking forward to seeing her in BR green, my current memories being only LNER apple. Again, we have many memories of its LNER guise, as well as all the pics, vids and films so let's have something different. 60163 looked best of all in BR green IMO, so let's do it.

 

Given the 75 mph limit on steam these days, the performance difference between 225 psi and 250 psi will not be of any great significance. Nor would the reversion to single chimney form IMO. 4771 never seemed to be hampered by it.

 

True re 4771, but what other differences between the two classes may have contributed to the V2 coping better with a single chimney ?

There must be advantages to using a double chimney surely, otherwise, why were so many locomotive designs converted ?

 

Agreed. If the intention of the double chimney is to enable the loco to work at its limit for longer periods of time then it will just get knackered sooner. The NRM is indeed in the business of education but given the extent and cost of the current overhaul , if running Scotsman into the ground is the intention, then that would be a lesson not learnt.

Jon

 

As a foreigner I like to stay outside the discussion, but I can answer a technical question.
Scaling laws in fluid dynamics tell us that a proper(!) front end could be replaced by two 71% scaled models, they would give identical performance as the original. However, since the chimneys are lengthened to the original length allowed by the loading gauge, we are not really scaling the original but a system with a 140% longer chimney. Since in a longer chimney the transfer of momentum results in an even more uniform exit velocity profile, a long chimney is advantageous. If the improved performance of the double chimneys is not needed fully, the blast cap area can be increased to bring performance back to the desired level.
As a consequence the locomotive has less backpressure and works more economical, the extra area at the bottom of the indicator diagram can be taken off from the expansion curve side. The identical argument is valid for the case with more orifices where the scaled chimneys are combined into a single one.
I hope to have explained this in a nutshell!
As for the changes from single to double and back, please note that a lot of these were poorly dimensioned in our present day views, I certainly do not wish to sound pedantic but almost all UK locomotives could do with a second look at the front-end!
Kind regards
Jos Koopmans

 

With my limited knowledge on the subject of draughting/exhaust systems, I'd have thought it was a given that the quieter a locomotive, the more efficient as less energy is being expended in making noise, which implies less constriction.

 

It hasn't got the original frames. All the original A1's had their frames changed in the 1930's (completed by 1937) and it was standard practice to replace the frames - which invariably arrived back at Doncaster cracked - with a repaired set at each general overhaul. This carried on right up to 1962 when 60103 had its last general. In fact comparing the loco that went in to the last general with what came out its questionable how much of the current Flying Scotsman was part of the same loco in say, 1959, let alone 1923.

The only possible 'original' condition it could be restored to is as it was after its last overhaul. Anything else would be a pastiche.

While I would still be grateful for anything else, I for one am much happier that it will be restored to its final 'normal' form, as a representative of this famous class in its final and most efficient condition. Note that if it is used it will almost certainly crack its frames again - it will just have to be budgeted for . Note also that they cracked their frames both in late 'Super A3' condition and in original A1 condition, so it will make no difference to that issue whatever chimney you put on.

 

It is unfortunate that only one A3 exists in preservation. At least with the preserved A4's we have a superficial choice of livery and currently valances or not. Not that I am suggesting for one moment a "single chimney" A4 retro.
With 60103, we can only have one configuration at any one time, and as the previous poster mentions, "as withdrawn from BR service" is a reasonable criteria.
Now, what if someone with strong views and very deep pockets came along? I wonder if that cylinder block from "Salmon Trout" still exists? Perhaps a red herring, so start afresh, provide the "new A3" with redesigned/strengthened frames, and if they wanted to correct something that happened under Thompson, recreate 4470 "Great Northern", either as it was before the hideous rebuild, an original Gresley "A1", or as an A3, which of course it never was. At least the new locomotive would have no "baggage" to hinder it.

46118

 

Ah yes my personal favourite part of this hobby, watching old(er)men argue about a completely changeable coat of paint.

I personally think that the Tornado people have it right by cycling through liveries giving us the benefit of seeing the loco in all conditions. Although as an aside to the Black Hat's post on p2 the Tornado group went apple not because of public demand but because the designers widow was giv en the choice and that was her favourite. I can never understand the militancy of those who insist that a loco belongs now and forever in x livery. Although usually it can be noted that the desire for a livery is a personal reminiscence thing masked by a usually fairly weak authenticity argument. Or of course the sure knowledge that the public would favour x or y. Ive often been told that the public would prefer apple because the number 4472 and the apple is known to the public and held up by them in high esteem. I strongly suspect that to most members of the public 4472 is an unknown element. Many if not most will know the term Flying Scotsman. They may even say its a train. wheter they know the loco/train difference is less likely still. whether ithey would attach the number to the name without much hinting is v unlikely. As said in previous post you could undoubtbly hang the name on Green Arrow and no one would notice. In fact I suspect that if you denied access to the NRM to enthusiasts and allowed in only the general public that you would be able to take 46229 keep it as is in streamlining with 6229 on the side,hanf the FS name on it and v v v few would notice that the fact that the big red machine with LMS on the tender was not Flying Scotsman and would go away happy that they had seen the celebrity A3.