Flying Scotsman

That's my understanding of it too. I doubt FS helped but I think he was done for financially even without that particular millstone.

 

Hindsight's a beautiful thing.

The kylchap and the smoke deflectors are of course, an improvement which in steam days gave the entire A3 class a new lease of life, bringing them up to standard with the other kylchap fitted locomotives in terms of steam raising ability.

To revert back to the original LNER single chimney fitting internally is - to me - questionable. You should want to retain the performance enhancement of the double kylchap for the purposes of reliability on the mainline, but equally the desire is there to revert the locomotive outwardly to the elegance of the single chimney fitting externally that suits it better with the LNER livery of course. The only alternative is to fit a different draughting arrangement - a Lempor or similar - if that is the aim. And why not? The locomotive has always been a working locomotive. The question of authenticity raises its head again.

I have sympathy for the NRM (Anthony Coulls who posts here in particular) - finding the balance between keeping the locomotive authentic, reliable and pleasing everyone on the colour question is a thankless task and a headache. Hopefully when she returns to steam we can be united in enjoying that and forgetting these issues for the time being.

 

I think I remember Steve Davies saying when he was in charge saying he would look into construction of a new single chimney for her but presumably isn't in question anymore.

My for my first Scotsman experience was in May 2000 (I was 8 at the time) when me and my Grandad booked us on a tour with Class 66 diesels to Newton Abbot Festival of Transport and 4472 was down on a tour that day there as well and stayed overnight. I was waiting for my Grandad who was paying for the car park at Slough when 4472 came flying through. We caught up with her at Newbury having a waterstop and got to Newton Abbot Racecourse to see her arrive as well. I have this picture of me with her (ignore the football shirt if your a rival fan).



I haven't as yet ridden behind her but hopefully 2015 will finally be the year (I have seen her on my NRM visits over the last 2 years). I don't care how see looks as long as she's back in steam again.

4472 will never be authentic In any livery unless people are willing to pay up for the costs of a new new single chimney casting or a non corridor tender. But can't say it bothers me too much how she looks.

 

I'd agree with the points you have there Martin, it is difficult to balance practicality with authenticity and aesthetics, more so for some then others. The forever ongoing issue of the Kings and the modifications they need to get more route availability is one notable example, albeit less of an authentic issue.

For stance on the 4472's guise is that it should have a single chimney, but as you've said with a different draughting arrangement, simply on the grounds that that is it's most recognisable form. Plus as has been mentioned before, NRM don't plan on straining it too much like what happenned to it so many times before, so really you have to wonder, are the benefits of the double chimney really worthwhile or needed if that's the case?

And finally there is one big issue in this debate which I think has been often overlooked, that with NRM being our centre of history of our railways, that also means that they have a certain obligation to be as acurate and authentic as possible with all the items in their care, 4472 epsecially so. If they must insist on keeping double chimney and deflectors, then their role in the responsibility of being as true to our railway heritage as possible must surely dictate that it will have to carry BR green, not the LNER guise, as authenticity is surely one of the top things you'd expect from a country museum of their railways, no?

In the end however, like everyone else here, I'll be happy just to see her running again, it's been too long old friend...

 

Single chimney or double Kylchap, so that is the question. Coal quality is not getting any better neither is the network getting less busy. The simple fact is that it is a steam locomotive and to carry out its work it needs? Yes, you've guessed it. Steam.

The Kylchap exhaust was worth around 500 hp, it reduced back pressure and improved steaming, old news, I know that I have posted this before. Now, I have no problem with the extra 500 but the extra 1000 possible with 250psi and 20" cylinders in conjunction with no frame improvements was rather too much. I also like locomotives to be free steaming, forgiving of poor fuel and of Firemen having a bad day.

So, since 4472 is best known as, well, 4472 and in LNER livery at that and the desire is for it to be authentic in appearance I wonder if a new single exhaust could be designed offering a significant improvement on the original? Any increase in blast pipe tip area would be welcome. A slight enlargement in chimney size would hardly be noticeable. So, what might be achieved and how could it be funded?

 

The Beano could perhaps start an appeal for it. I know their currently busy with raising funds for finishing off Lady of Legend, but it could certainly be a good appeal to do at some point (best time around the intermediate overhaul). They did something similar for 4472's vacuum brakes so it wouldn't be out of place of their appeals to do something for the single chimney too.

 

As for design work, I'd imagine the A1 trust could possibly help with that. Making new refined designs for fundamentally old machinary does seem to be their speciality.

 

Sheff, get the 5AT lot organised and see what sort of single exhaust system you can come up with ? could kill two birds with one stone and do away with the 'Gerry blinks' (which I love by the way) it may passify some of the posters on here, but it wouldn't be authentic at the end of the day !

 

Damn, beat me to it!

Would be an interesting exercise, even if only on paper..........

 

with the advent of computor designed mouldings made by image printers, for a fraction of the cost of traditional moulds it should be possible to mock up something , could a multi nozzle blastpipe be fabricated , rather than cast?

 

Alan Pegler, as a member of the BR Eastern Region board, supported fitting the A3s with double-kylchap and deflectors for exactly those performance reasons. Yet when he bought the loco he had them removed because he wanted it to appear as a typical LNER A3. Not 'authentic' - just 'typical'.

Agreed. As I've already said the NRM seem to have made their mind up for the moment and I respect their decision, even though I disagree with it.

 

Noted. I'll have a word ....

 

KESR fabricated an improved exhaust system for one of their USA tanks in order to prove the design. A casting was later produced once they were satisfied with the performance.

 

The 5AT group Lempor design is a mix of casting, fabrication and turnery. This allows the nozzles to be 'tuned' if necessary (it hasn't been yet) via a rapid swap once new nozzles have been machined. The nozzle size is calculated based on combustion and loco (ie cylinder) performance. So no mocking up is involved.

 

Three cylinder exhaust systems have usually been viewed as more difficult to optimise than two cylinder - pity Gresley was unable to complete W1 in pseudo three cylinder form. No matter, that is a game for another day. Did a quick sketch back from the chimney exit area once, was far from happy with it. What have you got on the Lemprex and improvements on the same?

 

That pretty much sums it up for me. I would have thought that it would have been the increase in boiler pressure that was responsible for over-stressing the loco, which will now be 220psi regardless of the exhaust system employed (prepared to be corrected though). Having said that I hadn't realised that the cylinder size had been increased. Have they now been sleeved back down to the original diameter?

For me, get her back where she belongs on the mail line 'as-is'. taking advantage of the better steaming and efficiencies afforded by the double kylchap. Whether to fit a single chimney, and whether to take advantage of more modern exhaust designs to maintain efficiency and steaming, is something that can be considered later. Subject to the wishes of the NRM of course.

 

"Three cylinder exhaust systems have usually been viewed as more difficult to optimise than two cylinder - pity Gresley was unable to complete W1 in pseudo three cylinder form. No matter, that is a game for another day. Did a quick sketch back from the chimney exit area once, was far from happy with it. What have you got on the Lemprex and improvements on the same?"


I'd have to check, but we are concentrating on validating our calculations for the Lempor in the short term. On the evidence from the KWVR's S160 so far they must be close to optimal, but we won't know for sure until we get the opportunity to instrument the loco and run trials.

 

That'll be an interesting "quantum leap"!

Sounds like you've got it right so far...........

 

.... the reason being that, on Gresley locos, the shorter inside con-rod/rearward positioning of the inside cylinder (chicken & egg) to clear the leading coupled axle necessitated a longer exhaust passage for said cylinder; hence the unevenly-spaced exhaust beats, despite setting the cranks to obtain the equivalent of 120 degree spacing.

Incidentally, my first ride behind 60103 was the 17:30-ish Doncaster (ex-King's Cross) to Leeds Central in January 1960. I was extremely p***ed-off that it wasn't the usual (34A) A4!

 

These Swindon Engineering Society lectures may be of interest to some:

No. 92 "The Arrangement of Locomotive Cylinders" by H. Holcroft, read Mar. 16th 1909.

No. 135 "The Modern Three-Cylinder Locomotive" by H. Holcroft, read Feb. 13th 1923.

Np. 184 "Practical setting of Locomotive Valves" by W. F. G. Aldridge, read Feb. 11th 1932.