Hello,
I've been reading Kratville's book on the Challenger Locomotives. An interesting read, at least for me, as I didn't really know much about about the CSA-1 and 2 series.
One comment from Kratville really intrigued me. On P. 144 he states "One peculiarity of the big Challengers however was there enormous coal appetite if not operated properly. If a crew did not use proper firing or the locomotive was not in fairly good working condition, a 3900 would go through a tenderful of Rock Springs coal in a hurry! The earlier design did not have this problem..."
I've have also seen in one of the video interviews with former crewmen that 3900s were not particularly easier to fire and if one made a mistake, is was not easy to recover.
I wondered if anyone had any thoughts about what made the 3800s more forgiving??
Thanks for any input!
You might want to find a copy of Eugene Huddleston's book where he compares the Fetter Challenger design to the N&W A.
One of the official pravdas out there is the idea that Fetter and Alco started with the general Nine idea, hinging the six-axle wheelbase in the middle while retaining the four-wheel lead truck, and going to four outside cylinders without need for derived motion. The four-wheel truck in the rear is only for weight bearing and distribution, and could as easily have been two-wheel, decidedly unlike the situation on deep-firebox engines like the N&W A or the Allegheny.
My interpretation of the firing issue would be commonalty with the observed Big Boy phenomenon of levitation of the crappy subbituminous coal fuel at high draft. This results in somewhat oil-firing style plume and heat release, as the part of the stoked feed that levitates is carbureted and ignited much as liquid fuel would be. However, the ability of the radiant-section uptake or the convection section to actually use this mass of fuel might be insufficient... meaning you get towering clouds of unburned fuel in the exhaust and a rapidly emptying tender.
Thanks Overmod for the reply.
I will see if I can lay my hands on a copy of Huddleston's book. Sounds interesting.
Your theory certainly seems plausible based on the amount of unburned coal that the late Challengers and Big Boys put out their stacks! After digging in a bit further Kratville's book also gives some numbers that seem to back that up.
The Fetter Challengers had 108 sq. ft grates with a Gaines arch 5'9" in front of the thoat sheet and a combustion chamber extending 86" forward of the throat sheet. Quite a bit of volume to burn up that levitated coal.
The Jabelmann Challengers had roughly 132 sq. ft grates and combustion chambers extending 106" forward of the throat sheet. I'm assuming the thought was the bigger grate would lessen the draft per square foot and allow more dwell time to burn the coal. However with that big MB stoker was throwing a lot of coal on the grate and plus the fines in the air, I could see where that would overwhelm the combustion area. One can only wonder how much more efficient the Big Challengers and Big Boys would have been with some better coal?
Thanks again for the insight!
Crappy coal going up the stack? The Chinese could tell you all about it.
https://www.youtube.com/watch?v=Ampco2JqSc8
The question of how much better a Big Boy would have been with with better quality coal has been asked before. I recall reading in the magazine a few years ago about how during testing it was found that the boiler could fully supply the demands of the machinery, so I suspect they and the Challengers wouldn't make much if any more power on better coal.
UP burned the poor-quality coal because it was dirt cheap and easily available in Wyoming, being produced in local mines (the same applies to the Rosebud coal that spurred Northern Pacific to build the first 4-8-4s). So while better coal likely would have resulted in less smoke and increased range UP's overall fuel costs probably would have gone up if they switched.
UP had coaling towers at strategic locations along their mainline, like many railroads, and refuellings would have been planned into the daily operation of trains. They would probably have to stop at many of those same locations anyway to take water.
Greetings from Alberta
-an Articulate Malcontent
SD70DudeThe question of how much better a Big Boy would have been with with better quality coal has been asked before.
A far better question in my opinion would be ways to improve operation using the subbituminous "more effectively". As noted that would involve better firing practices, but a wide variety of other changes including many of Chapelon's would improve things without hypothetically involving changing to different and at least ultimately higher-cost fuels.
You sure it wasn't L. D. Porta rather than his mentor A. Chapelon making that claim?
Chapelon visited the US, observed US designs and commented on their mechanical robustness -- I don't think he was "in" to expressing his desire to improve them, but Mr. Porta didn't have that social inhibition.
The other thing about using the low BTU coal more effectively, the grandparent post quoted a source that it was possible to get into a situation where one was firing them very ineffectively. It is worth learning more about what went wrong to blow a tender load of that coal up the stack in short order, although I am sure the locomotive was photogenic by US railfan standards when that happened?
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
Flintlock76Crappy coal going up the stack? The Chinese could tell you all about it. https://www.youtube.com/watch?v=Ampco2JqSc8
A illuminating video.
Never too old to have a happy childhood!
All I can say is WOW! Talk about wasted fuel...
Thanks for sharing.
Thanks for your input SD70dude.
I think I also remember reading somewhere that Big Boys produced all the steam needed, so I agree they probably wouldn't have produced more power. I am just curious how much less coal they could have used to produce that HP. More of a hypothetical question, as it would have been impractical to bring in coal from elsewhere. I'm sure that question has been answered somewhere as well.
Thanks again!
Overmod and Paul,
I think the questions of what design changes could have been made to use subbituminous more effectively and also what mistakes a fireman could make to get into a bad situation are very interesting. I know next to nothing about locomotive firing. Are there any resources that describe "proper firing techniques" for subituminous coal? Does anyone know if UP did any formal training for its firemen?It sounds like Chapelon or Porta had ideas on different designs. Are they referenced in books?
Thanks all
railracer Overmod and Paul, I think the questions of what design changes could have been made to use subbituminous more effectively and also what mistakes a fireman could make to get into a bad situation are very interesting. I know next to nothing about locomotive firing. Are there any resources that describe "proper firing techniques" for subituminous coal? Does anyone know if UP did any formal training for its firemen?It sounds like Chapelon or Porta had ideas on different designs. Are they referenced in books? Thanks all
Chapelon wrote "La Locomotive a Vapeur" (The Steam Locomotive) -- hard to get, never read it, Amazon seems to have used copies
La Locomotive a Vapeur: English Edition: Chapelon, Andre, Carpenter, George: 9780953652303: Amazon.com: Books
that are still pricey, I cannot tell if this is in the original French or is an English-language translation.
Wardale's "The Red Devil and Other Tales of the Age of Steam" lays out Porta's ideas. I read it when I was able to order its reprinting a few years back -- it is even more expensive on Amazon.
The Red Devil and Other Tales from the Age of Steam: Wardale, David: 9781909358010: Amazon.com: Books
The Coalition for Sustainable Rail "white papers" has interesting essays on Porta's ideas White Paper Program — Coalition for Sustainable Rail (csrail.org)
The Advanced Steam Traction Trust is a spinoff of Wardales abandoned 5AT project for a new-design steam locomotive for steam-enthusiast "fan trips" Advanced Steam Traction | Steaming into the Future (advanced-steam.org) -- they have information and pamphlets and books for sale.
railracer Thanks for your input SD70dude. I think I also remember reading somewhere that Big Boys produced all the steam needed, so I agree they probably wouldn't have produced more power. I am just curious how much less coal they could have used to produce that HP. More of a hypothetical question, as it would have been impractical to bring in coal from elsewhere. I'm sure that question has been answered somewhere as well. Thanks again!
There is that notorious Trains Magazine article "Big Boy -- Big Mistake?" claiming that the Big Boy and other "Super Power" steam locomotives were misapplied in service (Super Power was a Lima slogan for their 2 and 3-axle trailing truck locomotives with outsized fire grate area whereas the Big Boy was an ALCo product).
Bill Withuhn's posthumously published "American Steam Locomotive" lays out a case why the Big Boy should be considered a great success. The concept was to have enough tractive effort to take a 4000-ton train up the Wasatch Grade eastward from Ogden, Utah without a helper and have high enough drivers and enough boiler capacity to "run with that train" across Wyoming. It was combining these conflicting requirements along with the ability to use a locally source low-BTU coal into a single locomotive that lead to the unique 4-8-8-4 wheel arrangment along with its driver size. It also incorporated design concepts of the articulation hinge and front boiler support developed on the 2nd Challenger order for smooth high-speed operation. Withuhn chronicles the engineering tradeoffs in its design.
The 2-6-6-6 Allegheny (a Lima product for C&O and later Virginian) was successful enough, and more were built than the Big Boy, but Withuhn agrees with the Trains article that this locomotive was based more on "beating the Norfolk and Western 2-6-6-4 A-class" rather than the same sort of rational design of the locomotive for its service requirements as done by Union Pacific teamed with ALCo on the Big Boy.
The Allegheny was supplied a high-BTU Eastern coal and produced a record level of horsepower that was not achieved at its speed and tonnage rating in actual service, but giving it that high horsepower rating and fewer drivers than the Big Boy made it overweight for its total number of wheels, resulting in a record high axle load. Can't call it a failure because apart from suing Lima into losing money on this locomotive type, I guess the C&O had heavy enough rail to take the axle load.
C&O was famous for tolerating exordinate axle load in its locomotives, but that wasn't the reason the Alleghenies were so heavy... or the issue with their being 'overweight'.
If you compare the detail design of the Allegheny to the earlier N&W A, you'll be struck by the way in which steam mass flow is arranged from the throttle to the four cylinders and then back out the exhaust, with the pipes to the rear engine clearing the hinged forward one, and of course the forward engine's pipes being both 'flexible' and varying in length. The Allegheny does this with good large-diameter pipe and fittings, carefully flow-shaped. As I recall, no holds were barred in getting flow optimized... and all that plumbing is where much of the weight comes from. Meanwhile the Nicholsons in the firebox add much of the weight of multiple water legs ... a major reason for wanting three carrying axles in the space Super-Power Berks only needed two.
The problem was not that the engines were too heavy for the track or economical operation; it was that the unions (as part of acceptance of large articulated locomotives) had insisted upon a wage scale tied to the locomotive weight. Lima found it expedient to fib to C&O (and I think to Virginian) about the weight and, mirabile dictu, C&O somehow didn't weigh their purchases to confirm this right away. At least one author indicated that the additional wages abd settlement costs when this came to light wiped away much of the 'added profitability' the Alleghenies offered over the T-class engines...
Incidentally, Withuhn appears to be echoing Mr. Bruce in saying Alco 'invented' the idea of removing vertical hinging on the forward engine and accommodating vertical curvature entirely in the equalization. The A was designed for high speed, and uses this feature implicitly to achieve running stability.
All the references to the 'Big Boy' 'improvement' i have seen, including the drawings, have referenced Chapelon. I don't have my copy of Carpenter's translation but I don't believe the improvement project is in there; the original LLAV in French was published in 1938 and only sporadically updated postwar. I had the impression Chapelon was peddling the idea both of his 2-10-4 and some other improvements to America before the great die-off around 1947, and did the Big Boy more as a sort of 'teaser' about what American and French approaches could accomplish if fused than an actual 'design proposal'.
However, if any road could have benefited from the revised locomotive postwar (e.g. under real operating conditions, not wartime as benefited the PRR Q2s) it would have been UP, which would infamously go on to run trains with as many as 17 first-generation diesels -- all running -- and use a number of comparably high-horsepower consists while fuel prices permitted.
Much of the 'proper procedure' for firing the subbituminous fuel is probably undocumented today except by accident of preservation. I know of nothing like the Reading or NYC firing courses adapted to civer that fuel. What I suspect was one issue would be if the fireman allowed thin spots or holes in the grate, letting primary air into the firebox volume, when the engine had to be worked at long cutoff with high resulting draft. This would give conditions under which much of the stoked friable material would be levitated and ejected, going right through the firebox and chamber undissuaded by a Gaines wall or other flow disruption and quite likely without effective full ignition or 'flameholding' in the levitated plume length.
I have never read a reference that the ejecta from one of the engines in question was spectacularly reigniting upon exposure to atmosphere as at Sandoliang -- the many pictures just show 'burning-of-Rome-effects' black or brown smoke. (Of course I have not seen nighttime pictures of Jabelmann engines being worked hard...)
In my opinion correct firing of either a late Challenger or a Big Boy would involve very good attentive monitoring of the fire and prompt cleaning of dead spots and filling of thin ones, but also a certain amount of lifting of coal off the distribution table into the combustion plume at higher demand, a bit like mixed pulverized-coal firing. How easy the latter would be with the 'stock' stoker and jet controls, I don't know, and of course I have never tried it firsthand.
Overmod Incidentally, Withuhn appears to be echoing Mr. Bruce in saying Alco 'invented' the idea of removing vertical hinging on the forward engine and accommodating vertical curvature entirely in the equalization. The A was designed for high speed, and uses this feature implicitly to achieve running stability.
Holy scholarly citation, Batman! The Withuhn book is one citation after another of the Alfred Bruce book.
When I say 'echoing Bruce' I don't mean just citing the reference from American Locomotives. Bruce, God bless him, had a tendency to claim things for Alco done 'on his watch' that might be... shall we say a tad self-serving. Does Withuhn repeat his claim that he observed the Milwaukee A run at better than 128mph... more than once?
Mr. Withuhn, as I recall, early in his career stated unconditionally that T1s ran 125mph, and I believe he unquestioningly accepted Baldwin's assertion that the ATSF 3460 class were '120mph' locomotives, both of which caused me considerable grief in my youth until I determined for myself that their basis (like Crosby's story about a 120mph speedometer) was not entirely objectively demonstrable, at least not with any scholarly proof, citation or otherwise.
Overmod When I say 'echoing Bruce' I don't mean just citing the reference from American Locomotives. Bruce, God bless him, had a tendency to claim things for Alco done 'on his watch' that might be... shall we say a tad self-serving. Does Withuhn repeat his claim that he observed the Milwaukee A run at better than 128mph... more than once? Mr. Withuhn, as I recall, early in his career stated unconditionally that T1s ran 125mph, and I believe he unquestioningly accepted Baldwin's assertion that the ATSF 3460 class were '120mph' locomotives, both of which caused me considerable grief in my youth until I determined for myself that their basis (like Crosby's story about a 120mph speedometer) was not entirely objectively demonstrable, at least not with any scholarly proof, citation or otherwise.
Are you saying I am succumbing to the Gell-Mann effect?
Richard Feynman, who was a Nobel Laureate Caltech physicist, recruited Murray Gell-Mann to join him on the faculty of Caltech, hence becoming another Nobel Laureate Caltech physicist. Hard to say if they were good friends who were just kidding around or if they began to regard each other as rivals in scientific glory, but a Gell-Mann interview had him criticizing Feynman, who had preceded him in passing on, for a number of personal and social foibles, including Feynman's theories about dental hygiene.
Feynman didn't just "take it", he apparently made public how Gell-Mann was naive and eccentric, although the story was passed along by the late Harvard Medical School graduate and best selling author of sci-fi thrillers Michael Crichton.
The account is that Gell-Mann would accept at face value what he read about the Middle East whereas when he saw an article about physics research in the New York Times, he pounded his fist on the table saying, "Richard, every last thing in that article is just plain wrong! Why didn't they ask me for clarification of those points before going with it!"
Feynman thought his colleague Gell-Mann to be hopelessly naive to think that the article on the Middle East could be accepted at face value and wasn't equally a distortion owing to reporters at the New York Times knowing as little about the Middle East as they did about Physics breakthroughs.
Feynman was also invoking a principle well known in physics, that if a physical law, such as gravity, applied on Earth, the same law of gravity should apply to the swarm of stars circling a remote galaxy, that is, unless there is a reason to believe that "physics" worked differently at this remote location. Actually, the whole thing about Dark Matter is that it appears that gravity does works differently, and the physicists who crack that puzzle will be nominated for the Nobel Prize.
The distillation of the Gell-Mann effect is that if you have expert knowledge of a field, you will find that journalists have a third-grade level of misunderstanding of it, which should lead you to believe that the preponderance of what is in the newspaper is only loosely connected to what an expert would know to be true on any subject reported upon.
So am I naive that I accept Bruce's claims about the exploits of ALCo steam at face value, or that I am trusting of Withuhn's tall tales of the T1? Besides my research-engineering comic-book superhero Spidey sense, I think I have read enough skepticism to say, no, maybe the 999 didn't crack the 100 MPH or if it did, it didn't go 112 MPH, and Withuhn explains the mechanics of timing along with confirmation bias of persons observing mile markers and not even using proper stop watches used in racing or sporting events.
My Robin-sidekick-to-Batman remark about citations is that Withuhn has such dense citations to Bruce, Withuhn isn't just echoing Bruce, large sections of Withuhn are cribbed from Bruce, which I guess is OK for a history scholar if you include all the cites, but maybe a person should just read Bruce?
Part of the 'key' is that engineering and historiography are very different disciplines and should be conflated with great care and circumspection. This works, as with Feynman and Gell-Mann, both ways.
When we question a high-speed claim with steam, we can look to physics and thermodynamics to assess if a particular 'historical' claim is valid... but we have to be careful about what assumptions we use in modeling or experimentation. We can likewise correct for historical mistakes or design compromises, as was done in the early months of the T1Trust effort to be sure a 'practical' duplex could be engineered and built if it turned out (as it has not, so far) that the T1 as designed and improved by PRR had critical flaws impossible to cure.
One of the 'historical' smoking guns with the T1 is almost certainly the departure of Deasy and, in consequence a few months later, Duer. From that point forward we can date the abandonment of much of the steam research and practical betterment efforts, including the suite of detail-design improvements set to fix the major operational issues in first-line service in 1948... the engines would not see first-line service 'ever any more' under Symes, and I suspect some of the seeds of the too-convenient-failure explanation to get out of the equipment-trust obligation were being sown even then...
I have to work, but I'll get back to this interesting set of your observations later.
Paul MilenkovicThe distillation of the Gell-Mann effect is that if you have expert knowledge of a field, you will find that journalists have a third-grade level of misunderstanding of it, which should lead you to believe that the preponderance of what is in the newspaper is only loosely connected to what an expert would know to be true on any subject reported upon.
Reminds me of a comment I read years ago, by I don't remember who:
A person will believe everything they read in a newspaper until they read an article about a subject near and dear to that persons heart where the writer gets it all wrong. Then the trust is damaged or gone forever, never to return.
"If they got the subject I know about all wrong, what else are they getting wrong?"
Flintlock76 A person will believe everything they read in a newspaper until they read an article about a subject near and dear to that persons heart where the writer gets it all wrong. Then the trust is damaged or gone forever, never to return. "If they got the subject I know about all wrong, what else are they getting wrong?"
Which reminds me of my Palomar Mountain vs Mt Palomar rule for publications. The publications that use the former are making an effort to get the details right, where with publications that use the latter makes me wonder of what other details are wrong.
In th railfan world, the comparison might be Grand Central Terminl vs Grand Central Station.
I finally figured it out about why the late Challengers smoke so much and go through large amounts of fuel in relation to the early Challengers.
A crew on a late Challenger is under pressure to make up time, so the fireman may stoke too much coal on the fire?
Paul MilenkovicA crew on a late Challenger is under pressure to make up time, so the fireman may stoke too much coal on the fire?
Remember that the fire in a locomotive is not at all what you think of. It is not flames dancing on a hearth, or burner fire as in an incinerator. It is a white sheet of vaporized lambent carbon, glowing as a blackbody, suspended by a combination of physics ideally just out of contact with relatively cold boiler and chamber inner sheet surfaces, and ideally 'going out' by finishing combustion to full CO2 (which, remember, is transparent for EM of many wavelengths) just as it gets to the rear tubesheet.
Now, we watch our hypothetical firing practice start falling behind, and note that the steam pressure is starting to fall, so we stoke 'more and more' until the bed is heavy. This decreases primary air and chills the top of the firebed; the combination reducing the gas flow through the hot carbon. Draft is likely increased as a consequence of what made the steam pressure start to fall -- WOT with the reverse inching toward the corner to keep speed -- but the relaxation now has an increased component of 'various' secondary-air sources, some of which will be increasing the 'gas flow' across the distributing table of the stoker... where the elevator worm is completing the crunching-up of the subbituminous and likely discharging it with a relatively high component of fines.
(I pause briefly to remind everyone that the firebox volume is purposely run as a reducing atmosphere below atmospheric pressure)
Now what you'll see in this situation is increased fines lifting, trying to light off in the gas flow, but largely not succeeding in scrubbing gas to get adequate carburetor in the reducing atmosphere before their TOF brings them to the tubes where luminous combustion is quickly quenched (all reference I've seen say within 6"; some competent engineers including Matt Austin say 'virtually immediately' as far as heat transfer in the tubes is concerned). That does not mean the particles are extinguished; only that they're not glowing -- in fact, when ejected from the front end they may happily reignite spontaneously, which is what Goss referred to as 'sparks' and what produces the lovely effects of the Chinese engines.
Of course the tonnage of fuel that we see reigniting in the air contributes nothing to the locomotive's thermodynamics, but adds to the fuel bill just as if it did.
I'm really enjoying this discussion on how thermodynamics applies to steam locomotives.
It stands in stark contrast to the 'training' programs of many railroads during the steam era, where a new Fireman would write a basic rules and theory exam, make as few as three student trips, and then start working regularly.
They learned on the fly, some 'got it' and some didn't. The same is true for Engineers, some guys never learned how to run a locomotive efficiently, and others delighted in making the Fireman's life far more difficult than necessary.
Paul Milenkovic I finally figured it out about why the late Challengers smoke so much and go through large amounts of fuel in relation to the early Challengers. A crew on a late Challenger is under pressure to make up time, so the fireman may stoke too much coal on the fire?
"Early" and "Late" could have a double meaning, where instead of "Late" meaning the second major batch of locomotive production, it could possibly mean that the train is late, that is, behind schedule.
In honor of all of the dads out there on Fathers' Day, I offer this as a "dad joke", meaning a G-rated joke you can tell your young children but one that is otherwise not terribly funny.
A "dad joke" told by an airline pilot following a similar bit of comedic reasoning was just told on Rand Simberg's Transterrestrial Musings. A Southwest Airlines pilot pointed out the Arizona Meteor crater to the passengers on one side of the airplane who could see it, reminding that that a meteor excavated that gigantic crater some 50,000 years ago, but what is even more amazing, it just missed that little house.
I hope you enjoy your stay, and I will be here all week.
Paul Milenkovic...instead of "Late" meaning the second major batch of locomotive production, it could possibly mean that the train is late, that is, behind schedule.
Happy Dad's Day!
Paul Milenkovic, everything is better with cheddar! Have a great Father's Day behind The Cheddar Curtain!
SD70Dude ... They learned on the fly, some 'got it' and some didn't. The same is true for Engineers, some guys never learned how to run a locomotive efficiently, and others delighted in making the Fireman's life far more difficult than necessary.
...
During my Basic Officer Training when Canadian Forces Officer Candidate School (CFOCS) was in Chilliwack, we were four to a room in barracks. One of my roommates was hoping to be a helicopter pilot. He was an engineer, but in cartography. Guess...no really...guess why he failed out at CFOCS.
selector Guess...no really...guess why he failed out at CFOCS.
OK, map reading and land navigation?
When I was at The Basic School (For Marine Officers) the word was land navigation and map reading was the ONLY thing you had to pass to get out of there!
I stopped flying sailplanes when I realized, to my horror, that I could no longer recognize the changing terrain without frequent orientation using a map.
Sailplanes require fairly frequent turns where you have to be sensitive to ridge and thermal lift and not concentrating on 'where you are going' -- and you might be pointing 'anywhere' once you have come to altitude. On the other hand when you commit to land there is usually no such thing as a go-round, and it becomes much more tedious to recover the aircraft the further away from the staging point you come to rest -- further both horizontally and vertically.
Helicopters require more multiple control haptics than sailplanes...
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