Dedicated engine crews for a specific class sounds good on paper but it would founder on several hard realities. It would require a dedicated effort by the Motive Power people to ensure that a specific class would be consistently assigned to specific trains (possible on passenger schedules but somewhat difficult on freight). It would also require re-negotiation of labor contracts with the engineers and firemen to allow crew assignments for specific runs on a basis other than strict seniority (good luck with that). I'm aware that airline cockpit crews have to be certified on specific aircraft types as part of their crew assignment but let's back up to 1946 on this issue.
OvermodWell, there was that time that one of the Cardeans had only five drivers...
What an example of train handling! That could have been quite the disaster...
CSSHEGEWISCH Dedicated engine crews for a specific class sounds good on paper but it would founder on several hard realities.
Dedicated engine crews for a specific class sounds good on paper but it would founder on several hard realities.
Sad but true. The difference in average train travel distance was more of a factor here than in Europe as well.
Okay, as not to hijack this any further...
Where do you think the N&W would have gone given another decade?
NorthWest Okay, as not to hijack this any further... Where do you think the N&W would have gone given another decade?
I assume we would've seen some Y7 and Y8's. N&W had the heavy Mallet down to a science.
I'm not sure about the A's. If N&W stayed in its boundaries, there would likely be no development of the fast freight steam engine. However, if N&W did expand and merge with the Wabash and NKP, two notorious fast freight lines, maybe some A2's would've been built.
As for the J's, I'm afraid they would've been the last passenger steamers for the railroad. The 60s weren't kind to the passenger train, and the N&W didn't have any must-keep trains. The J's would have been kept going until the end of passenger rail, maybe with more assistance from newer fast freight engines.
Like the Y6, the S1 might have had a future. Switchers were needed in the 60s, and the S1 was the premier steam switcher. So maybe some S2's.
Hi Paul
quote >> Dedicated engine crews for a specific class sounds good on paper but it would founder on several hard realities.<<
Now , wait a minute - this proposal did *not* boil up in my brain - it was *reality* on several European railway systems and in fact was *common sense* during a long time of steam traction on these rys. : Just for example - without attempting complete listing :
LMS / LNER / GWR (SR ?) all major / most important engine classes on these 'Big Four' British railways from the Grouping to WW-II were run on fixed assignment , with double or triple crews .
PO-Midi / EST / NORD : at least on these - probably the other French railways to some extend , too - the most important engine classes were regularly run by 'machine titulaire' system with double crews , sometimes even single crews until WW-II .
DRG / DR / DB / DR-East : from the formation in 1920 to WW-II , all the more important engine classes were run on similar systems as the French , in German called 'Planlok-Einsatz' . This meant double or in cases single crew assignment of an engine . This system was inherited from the former Laenderbahnen , such as Bavarian , Prussian , Saxon , Wuerthembergian and others . Certain S 3/6 four cylinder compound engines on the Bavarian rys could have been run by single crew when assigned to run most important trains .
DRG and later DR also ran 01 / 03 class simple two cylinder Pacifics and other new built Standard classes on double manning in spite of their design specified for ease of maintenance and exchangeability of parts and whole components . This was resumed after WW-II on both West-German DB and East-German DR , from where DB went to 'Americanize' their steam traction significantly in multiple ways while DR kept fixed assignment for most of the members of more important engine classes , not just Pacifics but also 41 Mikado , 22 Reko dual purpose Mikado , 44 Decapod , 50-35 and 52-80 Reko classes of 50 and 52 Decapod and many more . Proven advantage was that engines were sure to be kept in - according to will and ability of crews - reasonably good to mint condition and could be expected to always rise to the occasion , turn out flawless reliability records and run on minimum of coal consumption . It was therefore very well found to pay off !
The reason DB dropped it depending on region and depot around late 1950s to mid '60s was definite aiming at replacing steam traction progressively and one consequence felt quite early on was top traffic being handed over to electric traction , which eased performance demands on steam considerably in most cases , although not in all . Where steam had to continue performing all out efforts , it was not before long that problems of reliability , performance level and increased maintenance costs and time arose . That was specifically the case with 01-10 three cylinder oil-fired Pacifics of Osnabrueck running the heavy express traffic on the 'Rennbahn ( 'race track' ) mostly level and straight on main line to Hamburg where engines were *by schedule* often asked to exceed nominal output during a large part of full throttle running time . Also , there were incidents with oil-fired 44 three cylinder Decapods of slipping and even exhausting boiler pressure and running to a stall on the long rising grades of hilly lines around Kassel , Frankfurt , Wuerzburg , where these engines were asked no less train loads on ramp sections than scheduled to E40 class electrics ,which arguably was well above what had once been established as nominal output by Grunewald testing . As friends told me who had witnessed that last period of steam traction , as late as 1973 Rheine shed tried to re-establish a triple manning of 012 class three cylinder oil-fired Pacifics in order to fight epidemics of drive gear failures and general very noticeable neglect of the last of these engines in service. The effort failed in spite of a dedicated shed management to get it working because general decline had by then been far beyond any point of return - crews were indifferent , they ran 'their engines' no better than common user engines , shed repair work was below any standards , engines were worn out and 'tired' in many ways , battered by multiple 'patch-up' sort of low quality repairs and so on . It was tried during the summer of 1973 and then given up , inevitable end came for the last six 012s in May 1975 when they had to be laid aside for insupportable technical condition ( a rare case in late steam traction that engines had to be given up before being bumped off traffic by electrification ; in fact an intermediate diesel traction had to be established to bridge the two remaining years until steam traction ended on the Emsland line and with it on DB in September 1977 )
>> It would require a dedicated effort by the Motive Power people to ensure that a specific class would be consistently assigned to specific trains <<
'It would require a dedicated effort by the Motive Power people' as an argument for impracticability of this system is bound to offer a remarkable insight to the quality of management of such railroads as concerned ! ( ..effort which obviously was unrealistic to expect ) From what can be read occasionally on the ways diesel traction is being 'managed' today's I wouldn't want to rule out that factor .
However , that would be a deficit of management rather than of that system or the locomotives concerned .
Regards
Juniatha
Oops... I'd forgotten we'd discussed the N&W a couple of days ago...sorry about that...
eagle1030 I'm not sure about the A's. If N&W stayed in its boundaries, there would likely be no development of the fast freight steam engine. However, if N&W did expand and merge with the Wabash and NKP, two notorious fast freight lines, maybe some A2's would've been built. As for the J's, I'm afraid they would've been the last passenger steamers for the railroad. The 60s weren't kind to the passenger train, and the N&W didn't have any must-keep trains. The J's would have been kept going until the end of passenger rail, maybe with more assistance from newer fast freight engines
As for the J's, I'm afraid they would've been the last passenger steamers for the railroad. The 60s weren't kind to the passenger train, and the N&W didn't have any must-keep trains. The J's would have been kept going until the end of passenger rail, maybe with more assistance from newer fast freight engines
The most likely scenario I can see for N&W's next passenger locomotive would be using the A's for dual service.
Okay, so... what other wheel arrangements could have we seen, including Duplex(insert two letters here)?
NorthWest Oops... I'd forgotten we'd discussed the N&W a couple of days ago...sorry about that... eagle1030 I'm not sure about the A's. If N&W stayed in its boundaries, there would likely be no development of the fast freight steam engine. However, if N&W did expand and merge with the Wabash and NKP, two notorious fast freight lines, maybe some A2's would've been built.
eagle1030 I'm not sure about the A's. If N&W stayed in its boundaries, there would likely be no development of the fast freight steam engine. However, if N&W did expand and merge with the Wabash and NKP, two notorious fast freight lines, maybe some A2's would've been built.
The As were being actively improved in the early Fifties, and I suspect (as did Ed King) that they were not actively "improved" further because there was relatively little wrong 'enough' with the design to make it cost-effective to change.
I think the proposal to adapt the Q2 boiler design was a particularly attractive "A-provement" -- there might be some fun discussing whether N&W would buy these new from Alco or someone else with the right kind of annealing furnace, or whether they would retain the riveted construction but without overconstraint at the waist, or whether they would themselves build the equipment to fabricate all-welded boilers. (I lean toward the last option...)
I do not know whether modifications to the Baker gear beyond putting the full-roller-bearing big ends on the eccentric rods were still required. I don't see N&W embracing poppet valves, no matter how efficient they might have been. I would have to think, at least, about going to Web-Spoke pattern for the driver centers to keep the rim distortion down. But the boiler swap would have been the big thing, and I suspect it would have provided a dramatic improvement -- be interesting to see just what could be done with it.
But let's not forget that the J was also as good a freight locomotive as ANYONE else's 4-8-4. And distinctly unlike something like a NKP Berk, no heavy augment forces at speed...
I don't know if the streamlining would have stayed long after passenger service ceased. We can speculate on which parts would go and which would stay.
Neither the A nor the J would have its 'niche' threatened by the TE-1 class.
Well, that's a good idea, seeing as the As were used as passenger locomotives almost from the first: Ed King notes that 1200 and 1201 were regulars on trains 40 and 41 (pp.70-71 of "The A") I have not seen any speed-test numbers on the last five built, with the lightweight roller rods, but you can expect there would be even lower augment -- even if it would be more difficult to implement 'perfect' rotating balance a la the J...
On the other hand, there would be precious few passenger trains that would merit a locomotive that size! More so in the '60s...
http://cs.trains.com/ctr/m/last-runs-before-amtrak/2085664.aspx
Looks like the FEF and 5 Es are working flat out! That could warrant a couple A's.
Does anyone know what changes would be made in the proposed Y-7?
Overmodthink the proposal to adapt the Q2 boiler design was a particularly attractive "A-provement" -- there might be some fun discussing whether N&W would buy these new from Alco or someone else with the right kind of annealing furnace, or whether they would retain the riveted construction but without overconstraint at the waist, or whether they would themselves build the equipment to fabricate all-welded boilers. (I lean toward the last option...)
As do I. They were always forward thinking in motive power. But would they have used a Belpaire Firebox?
OvermodI don't know if the streamlining would have stayed long after passenger service ceased. We can speculate on which parts would go and which would stay.
Rest assured, the J's look good without streamlining, too: http://cs.trains.com/trn/f/740/p/191804/2222530.aspx#2222530
OvermodWell, that's a good idea, seeing as the As were used as passenger locomotives almost from the first:
Someone remarked a while ago that the A's are the perfect fantrip locomotive: fast and strong. I agree.
Thanks,
NW
NorthWestDoes anyone know what changes would be made in the proposed Y-7?
Changes in what? The Y7 was very little like the Y6, if you were thinking the Y-7 was an evolution of the existing 2-8-8-2 design.
N&W got about a year and a half worth of work into the Y7 and there are documents at NWHS, including a diagram. I went back into the steam_tech archives and found
http://www.nwhs.org/archivesdb/listdocs.php?index=rs&id=2907&Type=Drawing [edit: this link is dead; see proper one below...]
Dave (feltonhill) might provide us with an idea of what else is there.
Figures from King's book on the A, p.77:
Driver diameter 63”Cylinders 26 x 30; valves 14”GA 130 sq.ft.“Heating surface” 7100 sq.ft. (with 23’ tubes/flues)Superheater area 2900 sq.ft.Starting TE 153,000HP (probably IHP, he doesn’t specify) “estimated in the 8,000 range at 40 mph.”
He says: "The Y-7 would have been one of the most powerful steam locomotives ever built, and its potential horsepower curve would have suited it admirably for use not only on N&W, but on other railroads faced with heavy tonnage in the mountains." One interesting thing to speculate on might be that, if this locomotive had been built, its design would have 'qualified' for production under the WPB restrictions in WWII -- which railroads that built heavy articulated steam might have opted for this design instead?
On the other hand, he mentions that by the time the kerfuffle about limiting freight trains to 70 cars had died down, the A and Y6 were doing the job well enough. As King puts it: "The utility of the Y-7 -- the districts upon which its capabilities would have proven advantageous -- would therefore have been more limited than originally believed."
I find it significant that in the postwar period, N&W opted to improve the A and Y classes, and then go to turbines, rather than build a simple-articulated (and higher-speed) 2-8-8-2. I would not expect to find much hard evidence of 'change' from the 1936 design and the postwar period, although there were certainly some areas where change could be applied. (For example, this might have been a locomotive, unlike others on N&W including the high-speed 4-8-4s, that merited disc main drivers...)
NorthWest Overmod I think the proposal to adapt the Q2 boiler design was a particularly attractive "A-provement" ... ... But would they have used a Belpaire Firebox?
Overmod I think the proposal to adapt the Q2 boiler design was a particularly attractive "A-provement" ...
... But would they have used a Belpaire Firebox?
You know, I had actually not thought about that. I can see arguments going either way (but will not discuss them here). Perhaps there are some details that survive at NWHS. My own suspicion is that N&W would adapt the design to what was needed, and that revision would not include a Belpaire... but that is only my opinion.
Oh, I thought it was an evolution of the Y-6. Well, I learn something every day.
I don't see them using a Belpaire.
Would the turbines or the Y-7 be more cost effective?
NorthWestWould the turbines or the Y-7 be more cost effective?
Depends a bit on how you define it.
I don't see the Y-7 as being as economical to run as the "improved" Y-6b. The 'Chapelonized' Y6 I described earlier would be even more economical, and probably just as fast as the Y-7 would have been.
Part of the discussion here implicitly assumes that N&W had a faster-freight service across the mountains. If that speed (not coal-train speed) fell within what a "Y-6c" (I joke this stands for 'Chapelonized' ...) could achieve, there is no point in building a larger and less-economical simple locomotive just for that service... in the 1950s. Likewise, the improved A class with Q2-pattern boiler is already knocking on the door from the other side, horsepower-wise, and while the improved adhesion of the Y-7 would be a small advantage, it would presume a higher average number of freight-cars in every train.
Meanwhile, the turbine (1) had roughly half the horsepower of a Y-7, (2) cost greatly more per example than a Y-7 would, (3) developed roughly similar starting TE (175K starting, which is higher and, of course, 'smoother' and 144K continuous); (4) would have had better efficiency on coal and water; and (5) would have required different gearing for fast freight service. This was a locomotive intended to do a Y-6s job, not a Y-7s. Which is not to say it couldn't be improved somewhat ... but Tom Blasingame, one of the proponents of modern STEs (steam turbine-electrics) looked very carefully into scaling it up to 6000 hp; there were the same problems with fuel and water that PRR observed for the "triplex"/V1, even with the higher nominal system efficiency.
Since the TE-1 was analyzed as being cost-effective with contemporary diesels, I don't have any hesitation in saying that it was seen at the time as competitive with reciprocating power. It might have been interesting to see how the 'future would have been' if more railroads had signed up for locomotive fleets of this type, bringing the per-unit and parts costs down and allowing the bugs to be worked out cost-effectively. For purposes of this thread: the cost may have been higher if there were no alternative use for the truck design used (I assume we are allowing straight electrics as permissible alternative power here?) as there would have been no C-C diesel-electrics to share development costs... but there are a number of clear advantages over even the best reciprocating power.
Ahh... I see. Different usages. Would the N&W have considered a 2-8-8-4? I'm not sure if it was needed or not.
NorthWest Would the N&W have considered a 2-8-8-4? I'm not sure if it was needed or not.
Would the N&W have considered a 2-8-8-4? I'm not sure if it was needed or not.
Not. The fact that N&W designed a large simple-expansion 2-8-8-2 rather than a 2-8-8-4, within a couple of years of the very successful A design, can be taken as one 'proof' of this.
If you look at servicing pictures of the A, you will see dramatic overhang. A 2-8-8-4 would require more. Plus more lateral-motion compensation.
2-8-8-2 has more weight on drivers. Perhaps more than expected, based only on the wheel arrangement, as the overhang provided for those lead/trail wheels is minimized in a way that is not usually practical for a two-axle trailing truck (where the pivot must be located very carefully so the rigid engine wheelbase and truck wheelbase both follow curves correctly).
Theoretically you could get an 'A-and-a-third' out of this, with proportionally better starting TE (from lower drivers, probably 63" for comparison with the Y-7). Presumably the 'extra' boiler length would be as a longer chamber, rather than increasing tube length (already on the 'long' side in the A boiler). With better balancing methods it might be possible to run as fast as freight needed to go without severe augment.
Too big for any sensible passenger assignment, except in wartime circumstances. Too big for fast freight. Not as good for coal trains as a shorter 2-8-8-2 of equivalent cylinder capacity...
In another list, we determined that Y-7 information is preserved here:
http://www.nwhs.org/archivesdb/detail.php?ID=90311
Isn't it interesting that Dave (feltonhill) is researching what I believe is this very book, getting details on the J balancing? At the next 'volunteer' session he attends, he might report what Y-7 material is there... ;-}
Hi Overmod!
Link activated: http://www.nwhs.org/archivesdb/detail.php?ID=90311
I see your points about the 2-8-8-4, with more weight on the drivers being more important than a larger firebox. Like how the Virginian managed to get by with 2-10-10-2s in drag service. And there was no reason to build it...
Dave, please post that information if you get it!
Last part of post moved here: http://cs.trains.com/trn/f/740/p/213216/2416504.aspx#2416504. I felt it didn't fit this thread.
Hi NorthWest
From what I have seen at the documents the boiler would have featured an extreme backward slope of inner and outer firebox , as in the A class boiler several times steeper than the steepest grade – why ? what was supposed to be gained by that ? a trifle bit of mass saving , yes , however at the expense of even shallower firebox space than typical with firebox-above-driven-wheels configuration . Main and coupled axle bearings would have featured the same or similar unique design as in the last batch A class , Baker valve gear and wheels of 15 spokes , same as in the A class and same btw as in a 52 class Decapod of smaller wheels and less than half the axle load – a rather coarse design for such a heavy machine . It would likely have had the blast nozzle design as in the A class , featuring six rectangular orifices arranged in a circle and of pretty much the same brutal anti-streamline compromised design at the transition from pipe to blast nozzle as can be seen in the UP design of multiple orifice blast nozzles for double chimney .
All in all Y-7 features look fully in line with hitherto N&W steam loco design , nothing new , nothing special - a locomotive composed of A class technology but with a different wheel arrangement , so to speak . That pretty much confirms my expectation , namely that steam development on the N&W would have come to rest on a platform of a certain level of basic completion , although that platform was more to the point than with other RRs . It is a bit disappointing to think the N&W would *still* have adhered to the same w/a and not have developed further the steam generation part of the locomotive - the extra mass involved in having a larger firebox volume by an behind-drivers arrangement would have more than paid off in performance .
Again , further development was being seeked in a total break of tradition – i.e. totally new unconventional steam rather than perfection of design of classic concept steam .
Since in the time frame left for steam development at the end of WW-II , short at any rate in view of diesels popping up everywhere and multiplying at fantastic rates , it must be considered very optimistic indeed to start a completely new line of development and hope to bring it to success within that time frame and against the overwhelming financial power supporting dieselization . Any such efforts were necessarily bound to fail . We may be wise by the light of hindsight - yet was it really beyond far sighted anticipation in 1945 ?
The only answer I can see to maybe have allowed steam another lease of life for an inevitably limited scope of time would have been a concentrated and vigorous development race for perfection of the classic concept – why ?
# because classic concept steam was proven and known to the railroads , new locomotives could be introduced at minimum effort and expense and effect a direct improvement .
# because it was proven and known to the builders , new power could be produced at a minimum of financial investment in technical development of design and new tooling equipment for construction ;
# because by relatively simple means advances were available , important enough to break even with or better on the best of contemporary diesels ;
# because even the most advanced of unconventional steam concepts , such as STE often mentioned here , could never have significantly enlarged that theoretical scope of time for steam since any STE was in the end bound to falter to diesel-electrics for fuel efficiency and specific mass per unit of power . STE could maybe have been developed to compete with classic concept steam at some realistic outlook , however it had little to offer that diesel-electrics didn’t and thus if successful at all STE would have won over the wrong competitor – I think it’s development was therefore not warranted , on the contrary has absorbed precious technical and financial means better to be used on developing classic concept steam .
A ‘modern steam’ which has repeatedly been mentioned in this and earlier threads without clearly defining what has to be understood by that term , in my view is a contradiction in itself – an anachronism by default if it is to cover steam locomotives of *any* concept built and run in revenue traction on any rail system in fully developed countries at least in times post turn of the millennium . Simply by its inherent double conversion of thermal energy any engine using fossil fuels to produce H2O steam as an engine working media *cannot* compete with more direct thermal engines and in our times past ‘peak oil’ it would not be advisable to use such engines .
In a nutshell this is why I believe steam inevitably had to end more or less the way it had developed – or : deviations for special cases notwithstanding , it had to go down that road until the road came to an end . Had it not been dropped around 1945 .. 47 in a way that imho had signs of an epidemic panic about it , at least on certain RRs steam new construction could technically-economically have competed through the 1950s and continued running in traffic during a fade out period through the 1960s , in cases into the mid 1970s – thereafter : no chance - except maybe in some limited cases of very special demands .
Juniatha, I agree that steam needed to come to an end, because of technical limitations. There were just too many things the diesel could do more economically, and steam just couldn't advance technically enough. The same thing may be happening with diesels now, look for a thread on that coming up. My idea of modern steam is to have let the existing steam locomotives be run until the end of their service lives, and no steam built after 1960. All Extreem Steeam wouldn't have been able to compete (except for possibly the "Hyper Heisler" in the other thread).
It is just fun to imagine what would happen if locomotives were to still be built through the '50s.
What things from ALCO do you imagine would have been built? (Sorry if we already discussed this, but I can't find it discussed in detail.)
What new ALCO power in post 1947 years :
Since they still felt the burns from their three cylinder (ad-)venture , all power strictly two cylinder only ;
little 'articulations' on or about SE Mallets , less on other 'Artics' .. yet finally a 2-10-4 of their own - and with advanced high tension steels becoming available maybe a 2-12-4 of some 100 t full b.p. piston thrust ;
a new strictly standardized GP 2-8-2 for secondary lines , a well balanced 2-10-2 succeeding the universal Berkshire ;
with Niagara success promoting it : more high wheeled 4-8-4 types and lighter 4-8-2 off-springs for lesser performance demands ;
However , in my view they should have revived the three cylinder machine in a fundamentally re-developed form , ousting the design weaknesses that had ruined them in the 1925s .
For that scenario I had put up drafts of some three cylinder types :
a dual purpose 4-10-6
a freight 2-12-6
a dual purpose 2-10-4
a definitely express 4-8-4
and another 4-4-2 .
Possible further types might have comprised :
the before posted 2-8-8-6 modified SE Mallet ,
a 2-6-6-4 dual purpose Duplex with 69 in wheels ..
= J =
JuniathaFor that scenario I had put up drafts of some three cylinder types :
Please tell us again where those drafts are located; I don't have a good link...
What is your opinion of using any of the existing poppet-valve systems on three-cylinder engines, and what would you propose as improvement on those systems for this purpose?
I think you addressed this already, but you might reprise it: if retaining piston valves on these various locomotives, what method(s) would you use to drive them?
Why is the Duplex a 2-6-6-4 while the twelve-coupled is a 2-12-6 (and the ten-coupled a 4-10-6)? There is probably some straightforward reason but I don't immediately recognize it.
Hi everyone!
A couple questions:
How would you solve the cutoff issues with the middle cylinder? Would you still use Gresley conjugated valve gear, or the "Double Walschaerts" valve gear used on some UP 9000s?
Wouldn't a rigid frame 2-6-6-4 duplex be a little long-framed for most lines? Especially with 69" drivers. I know that it wouldn't work on OW curves, but even some PRR lines might find it long.
Thanks for your thoughts,
NorthWest
NorthWest I know that it wouldn't work on OW curves
Just realized that that acronym may be confusing. I am referring to the New York, Ontario and Western. Also, the sound that one listening to a 10-coupled wheelbase try to negotiate that line would make.
Hi Juniatha!
I like your speculations about possible steam, but I'm not so sure about an ALCO revival of the three-cylinder concept. American 'roads weren't too crazy about three cylinders in the beginning, only the UP wen't for them in a big way with the 9000 series. The others just didn't like the increased maintanance requirments for a three cylinder job. Shop crews weren't too crazy about them either. I'm not ignoring the fact they were very successful in Europe, it's just in the American scheme of things I don't see how they would have worked out.
"GP" 2-8-2's for secondary lines? Certainly. The older steamers down-graded to branch line service were going to have to be replaced sometime. I would think six-coupled locomotives would have been needed as well.
Duplexii? Only the Pennsy seemed to be true believers in the duplex concept, but as time went by who knows? If the Pennsy made it work others might just have been interested.
As far as Norfolk and Western is concerned as long as Virginia Tech was turning out steam system engineers and N&W was grabbing them as soon as they graduated who knows where they might have gone? Fun to speculate on.
Wayne
Firelock76 ... I'm not so sure about an ALCO revival of the three-cylinder concept. American 'roads weren't too crazy about three cylinders in the beginning, only the UP went for them in a big way with the 9000 series. The others just didn't like the increased maintenance requirements for a three cylinder job.
There were a LOT more railroads that 'went for them' in the '20s; they just didn't last when better balancing let the required HP be produced out of just two 'bigger' outside cylinders, and the maintenance pains of the arrangement outweighed the perceived gain.
A 'first best' reason for Juniatha's revival of three cylinders is that they're needed to take best advantage of the rigid 12-coupled arrangement, just as on the UP 9000s. Even with 'unitary machinery support' two cylinders would have too high a thrust, and that with 90 degree quartering.
Personally I think it would be better, if you want a rigid-frame 12-coupled engine, to go to conjugated divided drive, with four cylinders, all outside. But there is added simplicity and shorter rigid wheelbase in the three-cylinder arrangement. For me, much of the 'future' in it (for purposes of this thread) would depend on poppet valves making the valve-gear-packaging issues less critical, and on better fabrication and materials for the inside rod and its bearings, probably with full pressure lubrication...
Certainly other 'roads went three cylinder, not just UP, but not a lot more, and as you said they didn't stay around too long. I didn't mention any others for the sake of brevity. If you're a maintanance headache you don't last too long.
I suppose a 12-coupled locomotive needed three cylinders to get the best out of it, but UP's 9000's were "oddballs" in their own right, really cool "oddballs" by the way, but no-one else tried the concept.
Ah yes, poppet valves. It's been said they came too late for American steam designers to really get the hang of them, a statement that's probably true. Had steam lasted, who knows?
friend611they would have built more J's to cover the remaining passenger assignments as the older K2 class Mountains were retired. They may have created a new unstreamlined J1 class to cover some fast freight assignments.
Why? The As were pretty good dual service locomotives. And the N&W saw, by the end, that streamlining wasn't necessary, buying GP9s instead of the concurrent FP9s.
Juniatha? I'm still curious about your 3 cylinder solution.
Yes, the N&W replaced the J's with GP-9's, but look a at a picture of the Powhatan Arrow with a J on the head end and then one with a Geep. It's not the same, just not the same, and never would be the same. The life went out of the train, and that's a fact. Foo.
I wonder how much their passenger revenues started to drop when the Geeps showed up.
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