-there is a good german article about that,
... condensing is a very special and limited technique ...
Those condensed steam has to be cooled down quickly to water and cooling also consumes a lot of energy...look at their big fans! Yet, on testing they could cool down 25tons of exhaust steam (metric) to 194°F hot water...
A steam locomotive and its auxiliaries is not big enough to carry huge cooling area and cooling appliances...
Those SAR-tenders were ridiculous big already, and they were far not as big engines like American's 4-8-4...
-lars
If it were a condensor engine a la S. Africa, it would do a lot better than having to stop at short intervals.
Unless, of course, we could figure out how to maintain track pans on grades.
-Crandell
Yes, Paul!
You're right! I thought it was a cleaverly done idea, and would give some folks a start to their saturday morning.
I would think a double articulated Garrett would be a power monster, but I would be curious if you could manage to pack on enough water and fuel, for a trip over even a moderately long run. I might be very doable for a specific situation where lots of power was needed over a specific obstacle. Like Sand Patch, or some of the VGN's or N&W's mainline grades. Just a thought.
Ah, the wonders of PhotoShop. All seriousness aside, though, the above picture suggests some of George Henderson's proposals for quadruplexes and quintuplexes (!) and a short article in TRAINS for a proposed Mallet-Garratt (4-8-8-4+4-8-8-4).
http://www.steamlocomotive.com/bigboy/bigbigboy.jpg
I see you fellows are still discussing BIG Steam!
I kinda thought the above linked Locomotive might be a subject for and R&D Project!
Enjoy!
daveklepperThe question remains: Why the S-1? What were they thinking of? Probably some good books have the answer, but what is it? One of kind, too long to really be practical, and designed before road power dieselization was seriously considered.
The question remains: Why the S-1? What were they thinking of? Probably some good books have the answer, but what is it? One of kind, too long to really be practical, and designed before road power dieselization was seriously considered.
The S-1 was 78' long, which is only 4' longer than a SD70ACe. The real culprit here was its 62' long tender. Put a more standard length 40' tender on the S-1, and the total length is now only 118', just slightly longer than the typical 4-8-4.
selectorHarveyK400Where would a T-1 make up time with frequent commuter stops on the NY&LB, much less overcoming a slower start than a J-1? That part is the deal breaker, I'm sure. If the distance between stops is much less than, say, 20 miles, the T1 would be mightily tested to make up time. -Crandell
HarveyK400Where would a T-1 make up time with frequent commuter stops on the NY&LB, much less overcoming a slower start than a J-1?
That part is the deal breaker, I'm sure. If the distance between stops is much less than, say, 20 miles, the T1 would be mightily tested to make up time.
A quick check of the map shows the distance between stops ranges from 1-6 miles - most in the 2-3 mile range. FWIW, only a couple expresses in 1966 Guide; but not leaving Penn Station 5-6 pm. So thoeretically, a J-1 restricted to 60 mph (don't know what Pennsy thought about that) might match the trip time of a T-1. There are engineering formulas to calculate this stuff; but you need a lot of data from the heat quality of the coal to the weight of the 12 cars.
HarveyK400FWIW, a J-1 would walk away on 68" drivers with 12 cars on the NY&LB.
FWIW, a J-1 would walk away on 68" drivers with 12 cars on the NY&LB.
The J1 had 69" drivers. It would certainly eliminate double headed K4s, but at passenger speeds, that 2-10-4 would also eliminate most of the track. Better have track gangs following in its wake of destruction and give the crews paid time off so their internal organs can recover from the pounding. LOL
GP40-2The only reason they completed their own end-of-steam designs was because at the time they had too much R&D tied up in them to stop. Their hope was to sell them to another RR that was more committed to steam, but no one was interested
Thinking about this,
... and we add Harvey400K's and others thoughts, look at the number of built engines containing their own design ( past '30 steam, excluding any typical Decapod or Mountain ... etc. design ...),
their steam railroad department seemed go to no-where...and those late '20 design 2-10-4 C&O T-Class were known one of the best on the PRR? Even equal power to Q2, correct? No blame on other designs... but they were..costly? Pushing limits?
However those late S2, from a theoretical standpoint, looked pretty well, I might thing...
-hard times for steam, though.
I
selectorBut if it got behind for some reason, it couldn't make up time as the T1 was capable of doing. The J1 would be capped at 70 mph, with some odd and rare exceptions, while the Duplex was known to exceed limits when it had to, and by a substantial margin. -Crandell
But if it got behind for some reason, it couldn't make up time as the T1 was capable of doing. The J1 would be capped at 70 mph, with some odd and rare exceptions, while the Duplex was known to exceed limits when it had to, and by a substantial margin.
Where would a T-1 make up time with frequent commuter stops on the NY&LB, much less overcoming a slower start than a J-1? I even wondered if a J-1 was balanced for more than 60 mph without pounding the daylights out of the track. It boils down to which engine, the T, M, or J, would be more economical with coal measured somehow against performance.
I'm guessing double-headed K-4s were a response to the need for better acceleration and speed overcoming the cost of a second engine crew and the limitation of the length of turntables.
I wasn't referring to the T-1, but the S-1, which was 140' engine + tender.
What were they smoking? How you gonna turn that baby without a wye?
John
GP40-2 The PRR T1 was 119' long, and 51 of those feet was due to its extended capacity long distance tender. The T1 itself was only 68' long - about the size of a SD40-2. To put that in prospective, the PRR J1 2-10-4 was 118' long, and most late steam 4-8-4s were around 115' long (give or take a few feet depending on tender capacity). So in that respect, the T1 was really no longer than most other late steam designs. Remember, the PRR original idea was to use the T1 in long distance service, so the long tender made sense.
The PRR T1 was 119' long, and 51 of those feet was due to its extended capacity long distance tender. The T1 itself was only 68' long - about the size of a SD40-2. To put that in prospective, the PRR J1 2-10-4 was 118' long, and most late steam 4-8-4s were around 115' long (give or take a few feet depending on tender capacity). So in that respect, the T1 was really no longer than most other late steam designs. Remember, the PRR original idea was to use the T1 in long distance service, so the long tender made sense.
UP 4-12-2I agree--what were they smoking when they were designing such long locomotives?
I agree--what were they smoking when they were designing such long locomotives?
HarveyK400But possibly too long for the South Amboy turntable?
http://www.raritanriver-rr.com/ForgottenHistory1Forgotten traces of the RRRR 20seenin the three official Raritan River Rail Road Company maps.htm
Are these maps related to those mentioned locations? Some plans contains a turntable, look at "Stevens" Ave shops"
daveklepperBack to lack of T-1's on the NY&LB. Thought comes the PRR already had a locomotive that could have avoided double heading: the M-1 Moutain 4-8-2. Would not it have adequate for the NY&LB commuter trains? But possibly too long for the South Amboy turntable? And the use of M-1 probably meant the PRR saw no reason for a 4-8-4 pre-WWII. But just what was the thinking that led to the S-1? Did they really plan on a system-wide infrastructure modification to be able to use this locomotive?
Back to lack of T-1's on the NY&LB. Thought comes the PRR already had a locomotive that could have avoided double heading: the M-1 Moutain 4-8-2. Would not it have adequate for the NY&LB commuter trains? But possibly too long for the South Amboy turntable? And the use of M-1 probably meant the PRR saw no reason for a 4-8-4 pre-WWII. But just what was the thinking that led to the S-1? Did they really plan on a system-wide infrastructure modification to be able to use this locomotive?
Interesting question about using M-1s on the NY&LB - certainly better than a single K-4 and about as good overall as the T-1. On the plus side, the M-1 had 72" drivers and simpler machinery. Other than the boiler pressure and grate area, was there much difference in heating surfaces between the two types?
As an earlier post pointed out though, turning engines may have been an issue, even with the original short tender. Anybody got anything specific?
Perhaps generally "in the same class"--BUT
NOT in the same class as compared to one particular road's SD40-2 versus all other SD40-2 variants, or one road's FT versus the others.
UP 4-12-2 It (the Big Boy) may appear similar to a Yellowstone, but I think UP was doing "their own thing" without having an eye on what NP/DM&IR were doing. Even in the mid-1930's, UP and NP had different design approaches on the original Challengers--that is well documented--the NP Challenger may look generally like an early UP Challenger, but they were different animals. NP's version had significantly higher starting tractive effort. John
It (the Big Boy) may appear similar to a Yellowstone, but I think UP was doing "their own thing" without having an eye on what NP/DM&IR were doing. Even in the mid-1930's, UP and NP had different design approaches on the original Challengers--that is well documented--the NP Challenger may look generally like an early UP Challenger, but they were different animals. NP's version had significantly higher starting tractive effort.
John,
Maybe they have done it unintended.
Do not know, how much they shared common avail. design parts or particular designs, buts lets say, all starts with some ( GSI - mostly ? ) casted frame, scaled up on a wished/designed/-frame...I mean the technical approach of such an engine. OK. you are right to say they were an equivalent stronger ( yet more expensive ) articulated than the Challengers in gen. UP service. But from outside they look more like a Yellowstone to me... ---do i feel wrong?
lars
-BTW. agree too that the team around Jabelman and Alco and more worked pretty hand in hand together as they have been ordered to...
Lars--
Yes, as I had said my figures come from The Challenger Locomotive book.
I don't have the Big Boy book. Ok, given the average figures you quoted, I'll buy the 3600 "average".
Regarding the contention that the Big Boy is really just a Yellowstone--I just cannot agree. From Kratville's writings which I have read, I do not recall any mention of UP having looked at the 2-8-8-4, but instead that they were interested in scaling up their own challenger.
In the history supplied with the new Athearn Genesis Big Boy model, it specifically states that "the easiest solution was to scale up the successful Challenger design by adding another pair of drivers to each half of the locomotive making a 4-8-8-4 design. The task before Jabelmann's department was to fit such a large machine into the real world." Athearn's history makes no mention of the 2-8-8-4's.
The Union Pacific often did things "their own way"--often disagreeing with and sometimes even outright ignoring ALCO's recommendations because they considered ALCO's position to be a rather "conservative" design philosophy. Case in point: Alco specifically stated the 4-12-2 was not designed for/should not be used at speeds above 35 mph. Union Pacific had absolutely no intention of running them that slow--but instead in the 40 to 60 mph range--and sometimes faster than that. Also--Alco wanted the middle blind drivers on the 4-12-2's, and 9000 was delivered with at least one set blind (no flanges)--but even before release for operation, UP replaced the wheelset with normal flanged wheels.
GP40-2My theory is that after the B&O's new diesel request was turned down, they used their political clout with the War Department (after all, Washington D.C. was their backyard) to get the EM1 design approved for production.
-interesting and plausible theory.
The years stood yet not still, and with a late 2-8-8-4 design the B&O take much of it as an advantage,
which seemed to have been paid out.
-The doom for UP-engines was, all the 800, 3900 and 4000 class was, at the end of WW2, accumulated running and maint. cost. was quite a percantage ( 3/4 or so ) of their whole purchasing costs... running those 4000 class especially, though they moved quite some tons.
They had the facility anyway ( mostly Cheyenne ), but after steam disappeared, I can tell exactly what happened with the RR-Town...
...1963, there was little left of it ;-)
-I very appreciate, that your nice Big Country still give nice reserve places for Big Engines...
Lars LocoSurprisingly, those "smallest" Yellowstone's were even were longer than the " big"M3/M4...
Surprisingly, those "smallest" Yellowstone's were even were longer than the " big"M3/M4...
locobasede Good morning, Boyd, and everyone else: I am the compiler of the data to which you referred in your post. It is extracted from a larger database that covers as many of the world's locomotives as there is data available. Wes Barris has been kind enough to host my data for several years. In addition to devising the process through which we could post as much data per locomotive as we do, Wes flags the obvious inaccuracies and passes along comments from visitors. Please also note that he offers his own commentary about many of the arrangements and classes on the home pages for each of those sections. During all of the time Wes has hosted the data, he has displayed my name and my email address. Several visitors to that site have contacted me through the email address with corrections, comments, questions, and points of discussion. Any of those contacts would tell you if asked that I respond positively, accept the comments willingly, and incorporate them readily. A review of the commentary on most of the entries will show the primary source's full bibliographic cite. In addition, I will include the identity of the person who contacted me with a correction and usually will quote him or her verbatim. In short, my door is always open and that stance does not reflect a recent change in policy.To respond to your specific inquiry about minimum rail weight. That's an actual calculation I unearthed in the Chicago & Eastern Illinois' Data on Locomotive Equipment book dated October 1, 1912. It is admittedly a simplistic calculation: Weight of drivers/number of drivers, which is divided by 3000. That result is multiplied by 10.Their example is 103,000 weight on the drivers/4 drivers = 27,750.27,750/3,000 = 8.58.8.58 x 10 = 85.8, which the Data Book describes as weight permissible per weight of rail. That's it. It's obviously a debatable formula, but my point is that it came from a book used by an operator in real-time railroading. I cannot tell you that those assigning the locomotives in fact believed that this was the only number they need; like you, Boyd, I doubt it. For one thing, the constant used in the calculation (3,000) undoubtedly changed at some point after 1912, or should have. But like most of the rest of the data I've included, it's sourced and the sources typically represent my attempt to convey what operators or knowledgeable commentators knew (or thought they knew) at the time this particular class was in service. (I'll admit to exceptions to that claim and offer no excuses other than lack of editorial resources.) As far as the minimum rail weight given for the C & O Allegheny. Doesn't the figure (141 lb/yard) underscore the weight problem that's been discussed when we take into account your comments about the actual weight/yard used at the time? Again, I welcome any comments about any of the entries. All of the designs that have been discussed in this thread have data and commentary available at steamlocomotive.com. Steve LlansoLocobasedelocobase@comcast.net
Good morning, Boyd, and everyone else:
I am the compiler of the data to which you referred in your post. It is extracted from a larger database that covers as many of the world's locomotives as there is data available.
Wes Barris has been kind enough to host my data for several years. In addition to devising the process through which we could post as much data per locomotive as we do, Wes flags the obvious inaccuracies and passes along comments from visitors. Please also note that he offers his own commentary about many of the arrangements and classes on the home pages for each of those sections.
During all of the time Wes has hosted the data, he has displayed my name and my email address. Several visitors to that site have contacted me through the email address with corrections, comments, questions, and points of discussion. Any of those contacts would tell you if asked that I respond positively, accept the comments willingly, and incorporate them readily.
A review of the commentary on most of the entries will show the primary source's full bibliographic cite. In addition, I will include the identity of the person who contacted me with a correction and usually will quote him or her verbatim.
In short, my door is always open and that stance does not reflect a recent change in policy.
To respond to your specific inquiry about minimum rail weight. That's an actual calculation I unearthed in the Chicago & Eastern Illinois' Data on Locomotive Equipment book dated October 1, 1912. It is admittedly a simplistic calculation:
Weight of drivers/number of drivers, which is divided by 3000. That result is multiplied by 10.
Their example is 103,000 weight on the drivers/4 drivers = 27,750.
27,750/3,000 = 8.58.
8.58 x 10 = 85.8, which the Data Book describes as weight permissible per weight of rail.
That's it. It's obviously a debatable formula, but my point is that it came from a book used by an operator in real-time railroading. I cannot tell you that those assigning the locomotives in fact believed that this was the only number they need; like you, Boyd, I doubt it. For one thing, the constant used in the calculation (3,000) undoubtedly changed at some point after 1912, or should have.
But like most of the rest of the data I've included, it's sourced and the sources typically represent my attempt to convey what operators or knowledgeable commentators knew (or thought they knew) at the time this particular class was in service. (I'll admit to exceptions to that claim and offer no excuses other than lack of editorial resources.)
As far as the minimum rail weight given for the C & O Allegheny. Doesn't the figure (141 lb/yard) underscore the weight problem that's been discussed when we take into account your comments about the actual weight/yard used at the time?
Again, I welcome any comments about any of the entries. All of the designs that have been discussed in this thread have data and commentary available at steamlocomotive.com.
Steve Llanso
Locobase
delocobase@comcast.net
Thank you Steve, for reply. Now, were those figures updated? Or where they specific to their own RR's?
A last thought on the idea of a T-1 on the NY&LB. Just possibly the turntable at South Amboy just wasn't long enough? At Bay Head there was a loop and complete trains were turned.
GP40-2I wouldn't consider the Big Boy scaled up at all
that is, why they were called the boys... big to attempt, but not grown up enough, yet...
young and wild ;-)
GP40-2I wouldn't consider the Big Boy scaled up at all. It was only 6 feet longer than the EM1
For John,
here is the quote from Kratville (Ogden/Riverdale to Wasatch, distance 62miles, elevation 4355ft - 6799ft):
Engine:
4014 : 3479tons av. speed 20.2 - av. draw-bar pull 64400lbf - av. DBHP 3415 (peak 5530 Devil's slide)
4016 : 3883tons - av. speed 19.5 - av. draw-bar pull 71000 -av. DBHP 3585 (peak 6290 M-P 958)
4004 : 3539tons -a v. speed 21.2 - av. draw-bar pull 64800 - av. DBHP 3570 (peak 5990 Peterson)
The runs were performed with different throttle + Reverse Lever positions ,also varying traffic occur.
That is realistic ---imo, of how much work is done, pulling such trains continuously uphill (except one mile, that is level ;-)
Hard working, they produced more than 4000DBHP at 14mph, with a load of 3883tons on 1.14% grade, so lets say 15mph speed minimum they were attempting in general on long grades. And there were certainly occasions, they lugged lower than this...
...John your figures seems to come from the "Challenger"-book...
UP 4-12-2Though it may look like a "scaled-up Yellowstone", the Big Boy was designed by Union Pacific's engineering department under Otto Jabelmann as a Challenger with two extra drive wheels. The design goal was for a Big Boy to pull the same train as a Challenger pulled over the flatter areas of the mainline, but to take it over the Wasatch mountains. Union Pacific never owned a Yellowstone. If you study the actual photographs, the UP Challenger heritage is quite obvious. Also, "3600 drawbar horsepower" appears to be a pretty low figure for Big Boys in actual operation. The Big Boys were rated to pull 4800 tons on a sustained 1% grade. This is from a Union Pacific motive power rating chart dated 1958, published in William Kratville's The Challenger Locomotive. The maximum cylinder horsepower of a Big Boy was rated at 6680 on that same chart from 1958. Obviously, drawbar horsepower is less--especially at lower speeds, but 3600 seems unrealistically low. John
Though it may look like a "scaled-up Yellowstone", the Big Boy was designed by Union Pacific's engineering department under Otto Jabelmann as a Challenger with two extra drive wheels. The design goal was for a Big Boy to pull the same train as a Challenger pulled over the flatter areas of the mainline, but to take it over the Wasatch mountains. Union Pacific never owned a Yellowstone. If you study the actual photographs, the UP Challenger heritage is quite obvious.
Also, "3600 drawbar horsepower" appears to be a pretty low figure for Big Boys in actual operation. The Big Boys were rated to pull 4800 tons on a sustained 1% grade. This is from a Union Pacific motive power rating chart dated 1958, published in William Kratville's The Challenger Locomotive. The maximum cylinder horsepower of a Big Boy was rated at 6680 on that same chart from 1958. Obviously, drawbar horsepower is less--especially at lower speeds, but 3600 seems unrealistically low.
UP 4-12-2If you study the actual photographs, the UP Challenger heritage is quite obvious.
Yes John, it is maybe just another point of view of mine, and the Big Boy was certainly built to UP standards, therefore its heritage...
But I am not so sure, to determine it as a scaled up Challenger. Look at GP40-2's comment above, it is basically a Yellowstone with an additional leading axle...
Hope to give support to this view: The BB was an all new design, improving the first "Baby" Challengers not just by power, also by - a new articulation design, casted frames, roller bearings, exhaust system, firebox...and more. However, the "heavy" Challengers were a scaled down Big Boy ;-)
Am I splitting hairs a bit to much of it?
Thank you GP-40 for your kind reply.
Hope you may answer another question of mine, what did they especially do enhancing the front-end?
Lars LocoThe Big Boy was just a part of it, a fast pacing-one.What I found pretty cool is the fact that the SP let them even run backwards, moving their unpivoted mass through curves...even with no roller-bearings? Leading passenger trains? Never read probs about them, though... another nice engineering ex.lars
The Big Boy was just a part of it, a fast pacing-one.
What I found pretty cool is the fact that the SP let them even run backwards, moving their unpivoted mass through curves...even with no roller-bearings? Leading passenger trains? Never read probs about them, though... another nice engineering ex.
GP40-2the Yellowstone Class was the ultimate all around heavy freight steam locomotive
Dear GP-40-2,
'44 seemed to be an interesting year, as many RR attempted to achieve ----- diesels, which were limited, although, and therefore not granted to every RR.
Their final steam-results were still impressive, based on first investment/HP, but not main- / running costs in the end (personal, I like those casted frames and roller bearings-/articulation-/suspension design).
I would better say, for ex., the Big boy were av. 3600+ DBHP engines uphill, than those allways proclaimed 6290HP peak, and this says a lot, comparing diesel like an FT or F3-threesome . Take a double headed 2-10-2 TTT uphill, that's pretty the same...
-The EM's seems to be nice engines, can you tell me more about them?
Th'x
--BTW "academic" is a fine way, calculated, theoretical or historical. Mostly I know is the last one, but tells the same story, if followed carefully like the first two ones ;-)
Lars Loco-interesting,did PRR ever had itself plans to built a own 4-8-4, or is this article based on a theoretical "what if " description? How realistic was it?lars
-interesting,
did PRR ever had itself plans to built a own 4-8-4, or is this article based on a theoretical "what if " description? How realistic was it?
I don't know if the PRR ever did seriously consider building/buying a 4-8-4. If they had an interest in the 1930's, they would have acted on it. IIRC, the PRR made an executive decision around 1944-45 to dieselize the entire operation, so they would of had no interest in a true end-of-steam 4-8-4 design such as the NYC Niagara or C&O J3a. The only reason they completed their own end-of-steam designs was because at the time they had too much R&D tied up in them to stop. Their hope was to sell them to another RR that was more committed to steam, but no one was interested.
The whole discussion about whether the N&W Class A or the C&O H8 is "better" is also academic in nature IMHO. There is a strong argument that both the N&W and C&O might of have been better off buying/building a late-steam 2-8-8-4 Yellowstone type of design for their general freight needs. Late model Yellowstone Class locomotives such as the M3/M4, Big Boy, and EM1 combined superior down-and-dirty lugging ability, high factors of adhesion, and the ability to run at high speeds in a single locomotive. While some other designs might have been slightly better in specific circumstances, in my view, the Yellowstone Class was the ultimate all around heavy freight steam locomotive.
The fact that the M3/M4, Big Boy, and EM1 lasted into the early 1960's on their respective RRs is a testament to their well thought out design.
There were at least two articles that dealt with what-if PRR 4-8-4s, but they are a long time back:
Keystone, Spring 1998, Vol.31, no.1
Keystone, Autumn 2000, Vol.33, no.3
I believe the topic of a PRR 4-8-4 was discussed in the 'Keystone' in the last few years - does anyone happen to know the Vol/Issue this article appears?
As an aside, I have really enjoyed watching this thread evolve over the last few months. Unfortunately I don't have the back issues containing many of the articles referenced. I've been keeping a eye out on eBay for back issues but I wonder if Kalmbach might consider packaging some of these into a future download package?
--Reed
Another point: The T-1 was designed to run Harrisburg - Chicago without engine change and had tenders that were supposed to handle this run without stops for refueling but with use of water track pans. In practice, engines were usually (eventually always) changed at Crestline. K-4's were never expected to run through Harrisburg - Chicago because the tenders simply were not large enough. and refuleing would have invovled as much time as changing engines at Crestline. Admittadly, the N&W J's never had a chance to perform such long distance service, but the Central's Niagras did and did so succesfully. I think the Pennsy may have experimented with a few K-4's that received tenders of the type used on the M-1, but this was towards the end when diesels were already being ordered.
Another take on the PRR steam locomotive designs: Their steam locomotive expertese may really have been dispersed with the onset of electrification. The K-5 improved Pacific program, leading to a Pacific that would truly match the Central's Hudsons, got sidetracked without the intense modification and testing that say the E-6 enjoyed. There was a program at the same time to develop a super Atlantic for lightwieght Congressionals, and this also got sidetracked.
Then came the development of the somewhat useless S-1. even more of a show-case unreal project than the C&0 2-6-6-6. In reality, the T-1 was an attempt to scale down the S-1 into something usable, and if they had started from scratch and been a bit less insular, perhaps a good 4-8-4 would have evolved. At the same time, the GG-1 was more successful than the R-1 4-8-4 electric. While other railroads were ordering streetcar-like electrics with motors on pivoting trucks geared to axles, the PRR used steam locomotive practice in the DD-1. Possbly the T-1 and the Q's reflected too much electric power influence. The more motors the better = the more cylinders the better! And possibly some of this was subconsious. Anyway, I am convinced that the PRR would have been better off with a good 4-8-4 than the T-1, and that buying Baldwin road diesels was also a mistake.
But I still appreciate the rides I had in PRR long distance coaches and once in a sleeper behind T-1's. It was a beautiful locomotive to see. Even if I like the N&W J even better,
I may be a day behind; but I wondered too about the specific rail weight. Most of the modulus of the track structure can be in decent ballast. By comparison, the C&NW Class H had 288,000 lbs on drivers and was said to be designed to run at 85 mph on only 100# rail. PRR laid some 140# rail early on, mostly in the East; but I ran across a stretch on the PFtW&C in Indiana which otherwise had 131# & 132# rail.
Dear feltonhill,
allow me to say first, to clarify, in no way my quote was intended to point critics on Wes' site, he does an awesome job there. I understand his page as a portal for browsing general infos about steam locomotives, but not all data can be compared directly ( which he points out also, many times ).
Lars,
Thanks for the link. Based on sampling most of the wheel arrangements, the formula used appears to be:
weight of rail = weight on drivers/(600 x number of driving axles)
or if you prefer:
weight of rail = axle loading/600
Never saw this formula before. I wonder where steam locomotive.com got it? Maybe it's another one of these mysterious yet simple ratios that give an answer the rest of us find too complicated to reduce to something so straightforward. Or wasn't this the underlying argument of this thread to start with? I don't like to sound skeptical so quickly, but the 600 x WOD divisor sound a little too pat for my liking. In my experience, tie spacing is also very important when it comes to supporting a given axle load. No such variable is in the above equation.
I don't regard the technical information on that site as all that good, although it's a convenient source to get a lot of stuff in one place. Unfortunately, I've found numerous errors in specs, and some of the descriptions are not very accurate. This is not a criticism of Wes Barris, who runs the site himself. He's at the mercy of his contributors, who have varying levels of expertise, and no one person can critique all the info on the site. I've found Wes to be very accepting of suggested modifications over the years when I found something out of line.
...while not intending to anticipate the answer; at "http://steamlocomotive.com/allegheny/?page=co"
the same value occurs (Minimum weight per yard of rail on which locomotive could run):
C&O H-8 - 1644 140 lb rail
C&O H-8 - 1600 141 lb rail
You will find corresponding minimum rail weights for almost every type at steamlocomotive.com,
but no explanation is given, how they calculated it or which source these data come from, unfortunately.
Where did you find the minimum rail weight requirement? This is a new one to me. Tie condition and spacing are usually considered more important than rail weight alone. According to track charts, C&O had 131RE and 132RE in general use on its main line in 1963. No 140-lb in sight.
...but why they get heavier during construction? I think LIMA knew how much all parts will weight.
Was LIMA let them built overweighted first and then being blamed later?
Did their weight lead to restrictions on their use at the C&O or Virg.?
I checked the articulated pages at www.steamlocomotive.com
C&O had a weight limit of 726,000 pounds. Lima and C&O's contract agreement was for an engine weight slightly less than that. During construction, the weight ballooned to allegedly as much as 778,000 pounds, and Lima later paid C&O a monetary penalty for the overweight engines.
The H-8 required 141 pound per yard rail. The N&W A class required 120.4 pound per yard rail--so it could run in many more places than the H-8 would be able to run.
UP 4-12-2--but it was never utilized by the C&O to its full potential.
I believe the true is, that they did all their jobs with ease while still having reserves. Using a steam locomotive without excessive firing rates is a nice way, saving fuel and keep nice efficiency levels.
UP 4-12-2"Adding to this rivalry is the fact that Lima built the 2-6-6-6 in 1941 more to "outperform the N&W A" than to meet the C&O's true traffic needs.
--why should they use the "A" as a reference, when they built with the T1 2-10-4 a very powerful locomotive 12 years ago already. The Allegheny with its high factor of adhesion was certainly a better engine for the mountains, than the "A", too.
UP 4-12-2And the Allegheny achieved its size and power at the expense of having the heaviest axle-loading of any steam locomotive ever built, which severely limited it to operating only on the very best constructed main lines.
Can somebody enlighten us what went wrong with building process and they were blamed being overweighted?
I think the builder (LIMA) could draw exact theoretical weights matching final weights.
Did someone dictated design rules that were not really necessary, making some parts of the locomotive heavier than they really need to be?
-I mean, before reweighting, did ever somebody noticed their overweight or did running problems occur ? The C&O a had a strong track plant anyway...
Cheers
Thanks for typing out the Boyd quote. As expected, he was just reporting that "The consensus [among railfan writers] seems to be ..." -- which is true enough. Much of Le Massena's article has indeed become the conventional wisdom among railfans.
After reading the above post I was able to find a couple of reference websites that the other posters on this thread might find of meaning within the context of this discussion:
First is: http://crestlineprr.com/duplexexperimentals.html
"Welcome to the Crestline PRR Engine Facility
The Duplex and Experimental Steam Engines of the PRR: The Crestline Connection"
FTA:"...What makes the Crestline Engine Facility such a special place? The reasons are many, among them is its geographical location, and therefore home to experimental and production duplex steam engines. Crestline is the eastern most division point facility between Pittsburgh and Chicago on the Ft. Wayne mainline. To the east are the foothills of the Appalachian Mountains. To the west are the flat lands of the midwestern plains..."
Second is this website:
http://findarticles.com/p/articles/mi_qa3943/is_200505/ai_n13642634/?tag=content;col1
FTA: "...A quick glance indicates that the C&O J3s and the PRRT1 were fairly similar with respect to engine weight, weight on drivers, grate area and engine tractive effort. A closer look, however, reveals a substantial difference in total tractive effort because the C&O J3s were equipped with boosters.
Description of tests
PRR 5511 was the first T1 loaned to the C&O for the test program, and received its initial assignment at Huntington, W. Va., on September 4, 1946. Before completion of the test runs, PRR recalled the locomotive on September 7, 1946, and replaced it with 5539 on September 11, 1946. T1 No. 5539 left C&O after a final run to Cincinnati on September 14, 1946..."
THis last website's article stretches to about 15 or so pages and is well researched and referenced at the end. It provides an unusually detailed description of the comparison tests of C&ORR operating conditions when tested with the PRR T-1 locomotive. It should prove of interest here.
If I may draw any conclusion from all the sources I've read, it's that, in general, the flatland or relatively flat areas of the U.S. were dieselized first--resulting in the early elimination of fine "state-of-the-art" steam power on many roads. Where steam survived "late" it seems to have been generally in the mountains, especially in pusher service where speed was not the priority as much as tonnage.
That's partly why the magnificent challengers of Western Pacific and Rio Grande were gone early (also inferior wartime steel boilers in the case of Rio Grande), yet the older 2-8-8-2's slogged it out longer in the mountains.
And again, if the PRR had bought its own version of the N&W J (possibly slighter higher driver diameter) or the NYC Niagra (The SP G-4 would have not met clearance restrictions), it would have done everything the T-1 did on the Broadway, Spirit of St. Louis, Tralblazer, Jeffersonian, and Red Arrow and still done a fine job in NY&LB commuter service, without any double heading. Incidentally, double-headed K-4's did often substitue for T-1's on the Broadway.
I don't claim to be a motive power expert. But it is clear that the Santa Fe, SP, N&W, NYC, UP, and the NKP, among others, had motive power design teams more in tune with the actual needs of the operating department than either the PRR (steam and diesel) or the C&O. I cannot fault the PRR with regard to electric power however. No one can complain about the GG-1, the B-1 Switcher , or the MP-54 mu car. The early PRR diesel purchases showed their Philadelphia loyalty to Baldwin. OK for switchers, but the road power was a big mistake, particularly since it could not mu with other diesels.
You might object that the Central never did use Niagras in commuter service after they were bumped from premium trains. Hudsons rarely. First, Boston suburban service, the largest suburban NYC user of steam power, was among the first services to be dieselized, as part of total deiselization of the B&A. Even the Highland Branch got diesels before it was turned over to the MTA for light rail. Second, most NYC suburban services that used steam power did use head-end lighting power, like the C&NW, Erie, and CNJ did. The PRR had pretty much stayed with axle-driven generators and large batteries on its P-70's, which were the NY&LB passenger stock, not the P-54's. The Central did not wish to equip Hudsons (a few were equipped and used out of NWP and Harmon) and Niagras with oversized generators. Hudsons, like K-4's on the PRR did occasionally show up on peddler freights, showing the flexiblity of a well-design passenger locomotive. I do not recall any NYC suburban steam trains sufficiently long as to require double heading with Pacifics or Hudsons (or 4-6-0's on the Putnam for that matter!).
timz UP 4-12-2Jim Boyd in The Steam Locomotive, page 136, clearly states that Lima designed the C&O 2-6-6-6 to outperform the N&W A rather than to meet C&O's true traffic needs. What did he actually say? I'm guessing he didn't actually claim to know anything about it-- he just offered a surmise, or quoted somebody else's surmise?
UP 4-12-2Jim Boyd in The Steam Locomotive, page 136, clearly states that Lima designed the C&O 2-6-6-6 to outperform the N&W A rather than to meet C&O's true traffic needs.
timz-
Well, no bibliography was given. Jim Boyd states in the front that the "hundreds of books" consulted for this project were far too numerous to mention.
After a comment that entire books were written that compare N&W 1218 to the 2-6-6-6, Jim Boyd stated the following on page 136:
"Adding to this rivalry is the fact that Lima built the 2-6-6-6 in 1941 more to "outperform the N&W A" than to meet the C&O's true traffic needs. The consensus seems to be that "Lima's Finest" did, indeed, have the potential to outperform the A--and nearly every other steam locomotive ever built, for that matter--but it was never utilized by the C&O to its full potential. And the Allegheny achieved its size and power at the expense of having the heaviest axle-loading of any steam locomotive ever built, which severely limited it to operating only on the very best constructed main lines. The N&W A, however, worked to its last days doing precisely the job for which it had been so well designed."
Again--no sources were specifically mentioned by name.
HarveyK400GP40-2HarveyK400You're ignoring the elephant in the room that the double-headed K4s took 2 engine crews. Am I? It would be much more economical to pay 2 crews to run 2 paid-off K4s in this type of service that they excel at, rather than invest millions in a modern end-of-steam design. Especially when it was literally the end of steam. HarveyK400I would have gone with the T-1 if clearances and axle loads were acceptable. Why? As feltonhill pointed out, the T1's were all wrong for this service. I just don't understand from a railroad point of view why you expect to use a locomotive designed for sustained 80-100 mph service, in stop-and-go operation.
GP40-2HarveyK400You're ignoring the elephant in the room that the double-headed K4s took 2 engine crews. Am I? It would be much more economical to pay 2 crews to run 2 paid-off K4s in this type of service that they excel at, rather than invest millions in a modern end-of-steam design. Especially when it was literally the end of steam. HarveyK400I would have gone with the T-1 if clearances and axle loads were acceptable. Why? As feltonhill pointed out, the T1's were all wrong for this service. I just don't understand from a railroad point of view why you expect to use a locomotive designed for sustained 80-100 mph service, in stop-and-go operation.
HarveyK400You're ignoring the elephant in the room that the double-headed K4s took 2 engine crews.
You're ignoring the elephant in the room that the double-headed K4s took 2 engine crews.
Am I? It would be much more economical to pay 2 crews to run 2 paid-off K4s in this type of service that they excel at, rather than invest millions in a modern end-of-steam design. Especially when it was literally the end of steam.
HarveyK400I would have gone with the T-1 if clearances and axle loads were acceptable.
Why? As feltonhill pointed out, the T1's were all wrong for this service. I just don't understand from a railroad point of view why you expect to use a locomotive designed for sustained 80-100 mph service, in stop-and-go operation.
I don't know the piston stroke or boiler pressure for either the K-4 or T-1; but both had 80" drivers and capable of 100 mph by recorded accounts. Whether only one was designed for sustained high speeds instead of stop-and-go operation seems to be splitting hairs or taking a comment out of context. The ability to produce steam would be crucial in either event, with little time to hook up, run more efficiently on expansion and recover boiler pressure other than while braking and dwelling at a stop. Both types of locomotive were capable of 60 mph or more between stations on the NY&LB; but with different size trains. This would be more than adequate to compete with driving.
It seems to me, and this is purely my opinion, and not "fact" to eventually be published in a book, that PRR reached a certain point with their design studies of steam power--and then conceded the inevitable.
At some point they obviously decided that further steam locomotive design would not be worthwhile and/or would shortly be eclipsed by diesels.
So while perhaps a few modern locomotive designs that didn't offer the heavily experimental features of the S and Q classes might have been beneficial to PRR, it seems they somehow realized those efforts would offer only short-term results--and let the diesel take over.
My 2c.
CSSHEGEWISCHCNJ's Train Masters performed quite well in the stop-start suburban service of the NY&LB, similar to what SP's Train Masters did on the Peninsula commute. They also did quite nicely in mine run and drag freight service on VGN/N&W.
CNJ's Train Masters performed quite well in the stop-start suburban service of the NY&LB, similar to what SP's Train Masters did on the Peninsula commute. They also did quite nicely in mine run and drag freight service on VGN/N&W.
What were the time lines for the K4 and Train Master on the NY&LB? 12 cars could be a stretch for a TM from comparable experience as a commuter on the C&NW.
I missed riding behind the Baby TMs on the C&NW before they were withdrawn from commuter service and assigned mostly to ore service in Upper Michigan. A comparable SD9 had better pickup for shorter train; and I don't know what was used on 11-car Harvard and Williams Bay trains before hard-pressed E-7s and eventually push-pull E-8s; or if 11-car trains with a single locomotive were even practical before then with the grades on the Wisconsin Div.
GP40-2...Besides, why would the PRR invest millions in late steam 4-8-4 technology for no name trains/commuter service, when a pair of simple, reliable, payed-off K4s can out performed any 4-8-4 made? That would be plain stupid.
...Besides, why would the PRR invest millions in late steam 4-8-4 technology for no name trains/commuter service, when a pair of simple, reliable, payed-off K4s can out performed any 4-8-4 made? That would be plain stupid.
You're ignoring the elephant in the room that the double-headed K4s took 2 engine crews. I would have gone with the T-1 if clearances and axle loads were acceptable. Running 2 shorter trains out of Penn Station would cost track capacity. Splitting the long trains to be manageable for a K4 would cost at least another conductor but allow faster express service to the outer terminal.
daveklepperI don't see any comflict between Jim Boyd's statement and my statement that the C&O's own people did not have much to do with the 2-6-6-6 design. If it wasn't the Allied Lines' committee, then it was pure Lima. And I accept Feltonhill's comment on the NY&LB. But isn't that, in itself, a real criticism of the T-1 design? That it was too specialized? In the late 40's could not the PRR have used a good 4-8-4, like the N&W J, systemwide on passenger service? Instead of the T-1? Remember the the SP Daylight 4-8-4's ended up giving excellent service in the San Jose commuter service, a service very similar to that of the NY&LB, after loosing their streamliner duties to diesels.
I don't see any comflict between Jim Boyd's statement and my statement that the C&O's own people did not have much to do with the 2-6-6-6 design. If it wasn't the Allied Lines' committee, then it was pure Lima.
And I accept Feltonhill's comment on the NY&LB. But isn't that, in itself, a real criticism of the T-1 design? That it was too specialized? In the late 40's could not the PRR have used a good 4-8-4, like the N&W J, systemwide on passenger service? Instead of the T-1? Remember the the SP Daylight 4-8-4's ended up giving excellent service in the San Jose commuter service, a service very similar to that of the NY&LB, after loosing their streamliner duties to diesels.
The T1 was not too specialized in the context that it did exactly what it was designed to do. The N&W J was all wrong for that type of service. Not enough high speed horsepower, and too high machinery speeds. Besides, why would the PRR invest millions in late steam 4-8-4 technology for no name trains/commuter service, when a pair of simple, reliable, payed-off K4s can out performed any 4-8-4 made? That would be plain stupid.
UP 4-12-2 ...Is Jim merely repeating what others before him have stated?
...Is Jim merely repeating what others before him have stated?
The 4 easy steps to write railfan book: 1) State your opinion as fact. Better yet, just make it up -- most railfans don't know the inner workings of a railroad well enough to notice the difference anyway. 2) Hope somebody else will write something using your opinion as a reference. This helps validate the "facts" you so carefully made up. 3) Somehow work the idea into your book that the C&O was run by idiots. Never mind the fact that they financially thrived and single handily formed one of the 4 remaining large U.S. railroads (CSX). 4) Repeat as needed.
LOL
Jim Boyd in The Steam Locomotive, page 136, clearly states that Lima designed the C&O 2-6-6-6 to outperform the N&W A rather than to meet C&O's true traffic needs. This seems to be at odds with the contention that the Advisory Mechanical Committee designed the 2-6-6-6.
Is Jim merely repeating what others before him have stated?
How involved was the Advisory Mechanical Committee after the Berkshires? Other sources I've read gave me the impression they really weren't involved much after the Berkshires...so why would they have been involved with a design that seems pretty much unique to/for C&O (and of course, Virginian)?
Which is closer to the truth?
Dave - Something you may not have considered in comparing K4's and T1's is that most of the NY&LB service requires fast acceleration and rapid braking on a repetitive basis. There was a reason the K4 survived so long. In addition to being simple and easy to keep going in the last days of steam, they were capable of accelerating relatively rapidly from one station stop to a maximum of 60 or so and hard braking back down to the next stop. Two K4's on a 13 + car train would be an even more potent combination.
The T1's were designed to run at sustained high speeds, and were not good at rapid acceleration in the low speed ranges. Consider the idea that a T1 was best operated at a moderate throttle setting up to about 25 mph then gradually bringing its power into play as speed increased. This would get a first class limited stop passenger train up to speed fast enough. However, in the NY&LB service brute acceleration was absolutely necessary. Based on a comparison of drawbar pull curves, two K4's would accelerate faster than a T1 up to about 40 mph. The 2K4/1T1 combination would be about equal at 50 mph and the single T1 would pull away above 50 mph. So although a T1 may have eliminated double-heading on longer trains, they probably would have been hard pressed to make the schedules because there would not be enough time spent in the 60-80 mph (or higher) speed ranges where they could start to shine.
Much as I like the T1 as a case study (spent over 18 years digging up info so far) , it was unfortunately a specialized design, too much so IMO. When their initial assignments vanished into the wave of dieselization, there was not much left that they could do very well, and they could not tolerate the deferred maintenance a K4 could..
Both the J's and the I's were last used in pusher service and the I's outlasted the J's in this service, then a few I's continued on in coal drags, so there is something to say for both your point of view and mine on this matter.
But K4's often double headed to get the longest of the NY&LB commuter trains (over twelve cars) to accelerate fast and make their schedules, and if they had been a real success and not required any more maintenance, the T-1's would have been fine for this job and would have eliminated double heading. They would have shared these duties with the K-4's, which would have handled the trains up to about twelve cars, and lasted to the end of passenger steam. Level territory, long trains, few speed restrictions, good clearances, the NY&LB would have wonderful T-1 territory, swapping with the GG-1's at South Amboy.
UP 4-12-2Yeah, obviously they could have bought better coal, but quite obviously the transportation costs were too high to make it worthwhile for them. Why else would they have chosen to design for the lesser grade of coal? No good designer would set out to design for the lesser grade coal unless it was the only practical, available option.
Yeah, obviously they could have bought better coal, but quite obviously the transportation costs were too high to make it worthwhile for them.
Why else would they have chosen to design for the lesser grade of coal? No good designer would set out to design for the lesser grade coal unless it was the only practical, available option.
From a bit after 1880 to the early 1920's, the NP was using Red Lodge coal, but developed the mine at Colstrip when the Red Lodge mines were nearing depletion. There was a lot of coal left in the Bear Creek mines just a few miles east of Red Lodge and transportation costs would have been similar.
The main reason that the NP turned to Colstrip was that a surface mine requires a lot less labor than an underground mine and the NP did mechanize the mine from the start. NP management presumably thought it was cheaper to buy locomotives with bigger fireboxes and burn the lower grade (and much cheaper) coal.
- Erik
CSSHEGEWISCH Le Massena dared to say that the H-8 was not an optimum design for C&O
CSSHEGEWISCH NP's Yellowstones would have been better performers if NP supplied them with good coal.
timz CSSHEGEWISCHhe dared to gore more than a few sacred cows Like what?CSSHEGEWISCH...and show that things were not always what they seemed.What wasn't what it seemed?
CSSHEGEWISCHhe dared to gore more than a few sacred cows
CSSHEGEWISCH...and show that things were not always what they seemed.
While I have little interest in steam (it died a long time ago), I have observed that many who have made postings on this forum regarding various steam locomotives get quite passionate beyond rational discussion in support of their favorite, be it the N&W A, the PRR T-1, UP Big Boy, C&O H-8, etc. Le Massena dared to say that the H-8 was not an optimum design for C&O or that NP's Yellowstones would have been better performers if NP supplied them with good coal. He attempted to move the discussion to a rational discourse, unfortunately, he does not seem to have been successful in this regard.
daveklepper C&O did continue to use its older 2-8-8-2's up to the end of steam.
Le Massena's greatest sin seems to be that he dared to gore more than a few sacred cows and show that things were not always what they seemed. He admitted early in the article that the whole matter was pretty subjective to begin with. I feel that he was attempting to inject some objectivity into the comparison of different steam locomotive designs, a difficult task at best.
daveklepperThe post mentioning the fact that essentially C&O motive power design was in large measure removed from local control and done by the Van's committee is the real answer. The C&O did continue to use its older 2-8-8-2's up to the end of steam. I think the last revenue steam operation on the C&O was a switcher, but before that if my memory is correct, the old 2-8-8-2's did outlast the more modern 2-6-6-6's. (Remember the PRR's T-1's disapearance long before the last K-4's; and their J's. copies of the C&O 2-10-4, going before the last I-10 2-10-0.) On the other hand, the N&W. UP. SP, CB&Q, and AT&SF (also to be fair, the NKP), ran their modern power to the end of steam. That says a lot.
The post mentioning the fact that essentially C&O motive power design was in large measure removed from local control and done by the Van's committee is the real answer. The C&O did continue to use its older 2-8-8-2's up to the end of steam. I think the last revenue steam operation on the C&O was a switcher, but before that if my memory is correct, the old 2-8-8-2's did outlast the more modern 2-6-6-6's. (Remember the PRR's T-1's disapearance long before the last K-4's; and their J's. copies of the C&O 2-10-4, going before the last I-10 2-10-0.) On the other hand, the N&W. UP. SP, CB&Q, and AT&SF (also to be fair, the NKP), ran their modern power to the end of steam. That says a lot.
UP 4-12-2 I'd love to have a chat with him, but am not sure he's even still available, much less how to contact him. There's lots of questions this 41 year old, who never saw the big guys run, would like to have the chance to ask. Yes--you are correct--those "misused" high speed simple articulateds did make excellent time over some divisions--which did lower operating costs. However, Huddleston also pointed out that nothing, absolutely nothing, performed as well over the mountainous sections of the Norfolk and Western as the Y-class, compound (slower) 2-8-8-2. For the particular profile N&W had to contend with, the high speed simple articulateds could do no better than the 2-8-8-2's in the mountains--and the 2-8-8-2's could start more train and make adequate enough time with it. Huddleston elaborated that if N&W had a profile like Virginian, with 0.3% grades to tidewater, they too might very well have opted for a magnificent fleet of 2-8-4's instead of the "mountain mauler" 2-8-8-2's. John
I'd love to have a chat with him, but am not sure he's even still available, much less how to contact him.
There's lots of questions this 41 year old, who never saw the big guys run, would like to have the chance to ask.
Yes--you are correct--those "misused" high speed simple articulateds did make excellent time over some divisions--which did lower operating costs. However, Huddleston also pointed out that nothing, absolutely nothing, performed as well over the mountainous sections of the Norfolk and Western as the Y-class, compound (slower) 2-8-8-2. For the particular profile N&W had to contend with, the high speed simple articulateds could do no better than the 2-8-8-2's in the mountains--and the 2-8-8-2's could start more train and make adequate enough time with it.
Huddleston elaborated that if N&W had a profile like Virginian, with 0.3% grades to tidewater, they too might very well have opted for a magnificent fleet of 2-8-4's instead of the "mountain mauler" 2-8-8-2's.
Well, since I'm obviously many years too young, and was not there, all I know about the big steam is what I've read in the various books, or seen in the various videos.
So far as browbeating Mr. LeMassena, that most certainly would never be my intention--I just wish I'd have the opportunity to visit with him and ask him some questions. Those who have are fortunate.
I appreciate his attempt to provide a locomotive power rating system with simplicity, whether or not it may have its flaws.
Lots of Santa Fe fans love their huge high horsepower, high speed 4-6-4's, 4-8-4's and 2-10-4's (which rate highly under LeMassena's system). Yet at the same time, when one really reads about their operational history, for all the marvelous power the 2-10-4's were a little slippery and a bit of a handful when operated over the up and down profile of the Arizona desert--such that Santa Fe tended to prefer their older 2-10-2's in the Arizona desert instead. That's one reason the 2-10-4's ended up in the New Mexico desert, and in helper service. Where I'm going with this is that, yeah, on paper the 5011 class 2-10-4 was a marvelous engine--yet many other authors believe the other roads' steam power like the big simple articulateds were superior in performance. Most Santa Fe fans generally esteem the 4-8-4's to be the best of the Santa Fe steam, generally superior to the more powerful 2-10-4's in actual operations.
The debate will likely last another 50 years...
BaltACDOne element I haven't heard discussed .... while the ruling grades are what the locomotives have to contend with for the pulling power.....the entire route of the trains is not the ruling grade. Once the ruling grade has been conquered there are still many miles of running that the trains have to do before the get to destination. Miles that the 'low speed' engine would have trouble sustaining 40 MPH....miles that those 'mis-used' high speed engines would jog along in the 40-50 MPH speed range with little effort at all. For a railroad, the efficiency of an engine is measuered from orign to destination...not just on the ruling grade.
One element I haven't heard discussed .... while the ruling grades are what the locomotives have to contend with for the pulling power.....the entire route of the trains is not the ruling grade. Once the ruling grade has been conquered there are still many miles of running that the trains have to do before the get to destination. Miles that the 'low speed' engine would have trouble sustaining 40 MPH....miles that those 'mis-used' high speed engines would jog along in the 40-50 MPH speed range with little effort at all.
For a railroad, the efficiency of an engine is measuered from orign to destination...not just on the ruling grade.
feltonhill FWIW, I last talked with LeMassena about 18 months ago (on another subject, not about this article). It was an interesting 80 minutes. At 93, he was trigger quick, knowledgeable and affable. However, he firmly believes that his simplistic formulations and ratios are absolutely correct and that's that. In his mind, no other approach is necessary. Needless to say, I just as firmly diagree with that idea, and with what I believe to be considerable good reasons. So I left it at that. The discussion was polite and inconclusive. I'm not into browbeating someone whose way more than a generation my senior.
FWIW, I last talked with LeMassena about 18 months ago (on another subject, not about this article). It was an interesting 80 minutes. At 93, he was trigger quick, knowledgeable and affable. However, he firmly believes that his simplistic formulations and ratios are absolutely correct and that's that. In his mind, no other approach is necessary. Needless to say, I just as firmly diagree with that idea, and with what I believe to be considerable good reasons. So I left it at that. The discussion was polite and inconclusive. I'm not into browbeating someone whose way more than a generation my senior.
Never too old to have a happy childhood!
Once over Blue Ridge, N&W had a profile that resembled the Virginian. They used Class A 2-6-6-4's east of Roanoke with a Y6 doubleheaded to Crewe and A's solo to Norfolk with up to 200 cars (loaded). A fleet of 2-8-4's would not have been the best choice for N&W; they were at least 1,000 DBHP too small for the job N&W needed to do..
Lima did not design the Allegheny to sell to C&O. The Allegheny specs were set by the Van Swerigen roads' advisory mechanical committee. Lima built what they were told to build.
C&O used the Alleghenies all over the system, not just on the eastbound ruling grade east of Hinton. There were plenty of miles with no significant grades, so they were not completely "misused.". However, since they did not pull any longer trains than the T-1 2-10-4's (about 160 cars max), what good were they? A modernized version of the T-1 would have probably been all C&O needed (IMO).
Somebody just might want to talk to Bob LeMassena and see what his reaction is.
While the A2 and H7 were given the same tonnage rating due possibly from higher A2 axle load, could the A2 achieve a higher speed, 25-40 mph, with its greater boiler horsepower?
I haven't read all of these posts, but this is a fascinating discussion nonetheless.
Regarding the alleged misuse of the 2-6-6-6, I found some of Dr. Huddleston's comments in The World's Greatest Steam Locomotives very interesting:
The C&O had the exact same tonnage rating on some grades for both the H7 2-8-8-2 and the 2-6-6-6.
So for all the engineering and investment in the newer 2-6-6-6, what did C&O really get, in terms of applied real world power on the railroad? What was really gained other than newer, more reliable power?
Some have suggested that more 2-10-4's might have been equally as effective as the 2-6-6-6 in real world service on the railroad. Could this be true?
Huddleston commented that the 2-6-6-6 was designed specifically to beat the Norfolk and Western A Class in power output. Did Lima sell the coal roads (C&O and Virginian) more engine than they really needed just so they could one-up N&W? Could an improved 2-10-4 have been a better choice?
It's also interesting--as Huddleston points out--that UP, also on the exact same sustained grade as some C&O tonnage ratings (1.14%) gave the ex-C&O H7's a higher tonnage rating than C&O did--while at the same time, the Big Boy tonnage ratings were even higher than the H7's. He felt C&O was conservative with tonnage ratings--not wanting to tie up a mainline if something went wrong. Huddleston logically concluded that UP would have given the Big Boys a higher tonnage rating than the Alleghenies (because the Allegheny and the H7 were comparable). From a logic view, that makes sense, but...
Another fan who seems not to have given the puzzle a thought was William Withuhn in his article in 6/74 Trains: "The railroads' habit of grossly misusing their steam has been mentioned here in TRAINS, but the implications really never have been worked out. Time and again a modern steamer, specifically suited for a speed regime of 30 to 60 mph, was put to use at 10 to 20 mph. The Allegheny type perhaps was the best (or the worst) example of this." The 2-6+6-6 "developed its best drawbar horsepower, and reached proper running efficiency, at 35 to 45 mph. How was this engine used primarily from its first day? In drag coal service, of course-- and by C&O, which should have known better. This sort of situation happened time and again. Using high-speed engines in high-speed service, and designing actual low-speed engines for low-speed service, apparently were concepts too difficult to grasp." Far as I can see, the "difficult concepts" here are the same as before, and quite undifficult: longer trains require more TE, more TE requires more drivers, etc. Can anyone find anything in that article beyond that? (Similar was Bert Pennypacker's article in April 1992 Trains on the WM 4-6+6-4s, where he said the railroad "probably would have been far better off" with a 2-8+8-4.)
More from the article: "Neither company [C&O or DM&IR] seemed to recognize that the high-capacity steam locomotive delivered the most ton-miles per train-hour at speeds close to that corresponding with maximum power output. This may have made little difference to the captive DM&IR, but understanding the C&O's attitude is difficult. DM&IR dragged immense loads of iron ore from the mines to the docks, while the C&O used its massive 2-6-6-6's in coal-drag service well below their maximum abilities." Le Massena clearly thinks C&O was stupid to get a fleet of 2-6+6-6s-- what isn't clear is what he thinks they should have done with them, given that they had saddled themselves with such unsuitable engines. What C&O did was pair them on 11500-ton coal trains up the 0.57% to Alleghany; does Le Massena think they would have saved money by pairing 2-6+6-6s on, say, 8000-ton trains instead? Hard to see why they would-- but apparently that's what he thinks about DM&IR, so maybe he thinks it about C&O too. In any case he thinks the C&O would have been better off with a fleet of 16-driver engines, or maybe 20-driver. (I can't tell whether any design of simple Mallet would have satisfied him-- likely not.) The obvious question: why did they choose fewer drivers, anyway? To us fans it is puzzling, and it's going to remain so. An engine with 150,000 lb nominal TE will pull more cars up a given grade than an engine with 110,000 lb-- we know that for sure, and presumably C&O did too. To get 150,000 lb TE we need 16 drivers or more-- C&O knew that too. I'd say we fans can't come up with any relevant fact that wasn't equally obvious to the C&O-- yet they bought 2-6+6-6s, which makes no sense to us. Far as we can tell from the article Le Massena never gave this puzzle a thought-- a glaring omission, if true. Probably most readers give him the benefit of the doubt, figuring he must have come up with some reasonable explanation that he didn't want to bore them with. Maybe it's even true-- hard to see how he could be that serenely oblivious. But the explanation is hard to reconstruct.
GP40-2The B&O also did a lot of experimenting with water tube boiler locomotives. While it is possible to have a large direct heating area and run higher pressure than a fire tube boiler, the B&O mechanical engineers found that water tube boilers where just too fragile in the railroad world. What everybody realized by the mid 1940's was that the fire tubes simply did not add as much to steam production as originally expected. Boiler design changed to emphasize direct heating area, while the shorter fire tubes pretty much served as "exhaust pipes" to get the spent gasses out to the stack as quickly as possible.
The June 1967 article on the D&H high pressure experimentals ended up with a comment that every time one of them went out on the road, the machine shop had to follow it. OTOH, the watertube concept did show up in a lot of locomotive designs in the form of thermic siphons.
I can think of a couple of ways that the extended combustion chamber helped. The first in that the large volume of gas would be radiating heat like crazy (direct heating surface) - radiative heat transfer is proportional to the 4th power of the temperature compared with linear for convection - I would imagine that there were copious amounts of incandescent carbon particles in the combustion chamber. The second is that the combustion chamber would give those carbon particles at least a few more milli-seconds to burn before they're shot up the stack.
Firebox (or direct) heating surface was one of the considerations that went into the formulas I described in my December 24 reply. (You can see a concise explanation at Wes Barris's steamlocomotive.com.) Here are the components of the formula:
(Direct heating surface+ (superheating surface*1.5)+((tube+flue heating surface)/6)*driver diameter)/HP cylinder volume). I multiply HP cylinder volume by 100 just to keep the final number in bounds). Both the 1.5 multiplier for the SHS and the division by 6 of the tube & flue is based on railroad practice.
Key point - this formula is an attempt to present available steam at speed and does NOT take into account tractive power. Multiplying the total heating surface area (direct, superheater, and tube&flue) by the driver diameter takes into account the number of times per mile the cylinders will be refilled. You could substitute RPM and achieve the same comparative result.
Notice that with compounds, I'm only taking the live steam after starting.
Just as a sample of the interesting results, go to Steamlocomotive.com, find the Lima-built H-10 2-8-2 that set the tone for superpower on the New York Central (Locobase 9696) and a Missouri Pacific Mike that was rebuilt with thermic syphons in the firebox (Locobase 24 - MP 1426-1570). Both come from the same era, had the same driver diameter and boiler pressure. The H-10 had a bigger grate, not quite 10% more firebox area, and more superheater area. Its SPR (the "SuperPower Rating") is 21,661 compared to the MP's 15,053 (a 43% difference).
I'd love to see any comments on this reasoning.
Also (and this may start another, much smaller thread), I'm looking for information on when and where the Central of Georgia's two 2-6-4Ts ran. Did they perform similar duties to those of the Tennessee Coal Iron & Railroad's 4-6-4 30.9.3s, which delivered miners to coal mines? (Locobase 7310)?
erikemGP40-2It had a lot to do with the direct heating surface available, more so than the total heating surface. A common "end of steam" design was to use shorter, larger diameter fire tubes and lengthen the combustion chamber. In addition, larger arch tubes and multiple thermic syphons would often be employed to increase the direct heating surface. One of the things that struck me in the article on the D&H high pressure experimentals (June 1967 Trains) was the discussion of how much more effective heating area was in the firebox as opposed to the flues. The D&H high pressure locomotives traded off a lot of flue area in favor of heating surface in the firebox - somewhat easy to do with watertube boilers. Took me thirty to realize the difference was radiant (direct) heat transfer in the firebox versus convective heat transfer in the flues.- ErikP.S. There's a nice picture of the boiler for D&H 1400 on Doug Self's "Loco Locomotives" website.
GP40-2It had a lot to do with the direct heating surface available, more so than the total heating surface. A common "end of steam" design was to use shorter, larger diameter fire tubes and lengthen the combustion chamber. In addition, larger arch tubes and multiple thermic syphons would often be employed to increase the direct heating surface.
It had a lot to do with the direct heating surface available, more so than the total heating surface. A common "end of steam" design was to use shorter, larger diameter fire tubes and lengthen the combustion chamber. In addition, larger arch tubes and multiple thermic syphons would often be employed to increase the direct heating surface.
One of the things that struck me in the article on the D&H high pressure experimentals (June 1967 Trains) was the discussion of how much more effective heating area was in the firebox as opposed to the flues. The D&H high pressure locomotives traded off a lot of flue area in favor of heating surface in the firebox - somewhat easy to do with watertube boilers. Took me thirty to realize the difference was radiant (direct) heat transfer in the firebox versus convective heat transfer in the flues.
P.S. There's a nice picture of the boiler for D&H 1400 on Doug Self's "Loco Locomotives" website.
here is an example, of how boiler and smokeboxes grew. Though the angle of the photo is twisted, the back of the caps is in one line - Bullmoose, Y3a, 9000, Heavy. Chall., BB:
Actually, the early 3900class is missing here, the boiler and firebox-length of the late3900 class Challenger grew in length a portion in comp. with a 9000, the Y3a has a longer boiler and bigger firebox than the Bull Moose, but has shorter smoke box
-hope, you enjoy!
Lars Loco Using shorter, larger diameter fire tubes would actually lower the total heating surface available, but had great benefits. The larger diameter fire tubes would allow a free flowing exhaust, and the shorter length allowed a longer combustion chamber design. The result was a boiler that on paper looked "smaller" than an older design with a higher number of longer, smaller fire tubes, but was more powerful. Excellent explanation here of boiler design. Does Le Massena's "formula" takes concern of that?
Using shorter, larger diameter fire tubes would actually lower the total heating surface available, but had great benefits. The larger diameter fire tubes would allow a free flowing exhaust, and the shorter length allowed a longer combustion chamber design. The result was a boiler that on paper looked "smaller" than an older design with a higher number of longer, smaller fire tubes, but was more powerful.
Excellent explanation here of boiler design. Does Le Massena's "formula" takes concern of that?
I had always read that NKP turned their Berkshires quickly, as did N&W their big steam power--in both cases routinely under 2 hours.
However, Kratville and Bush in the UP Type Vol. 2 book indicate that during hurry periods Union Pacific actually turned engines in as little as 25 minutes (obviously without the washdown but with a quick inspection over the drop pit). Since this included turning 4-12-2's in 25 minutes, it is quite obvious that the middle cylinder would not always have received the maintenance it needed.
Big Boy boiler was considered free steaming according to Kratville, and had the ability to raise large amounts of steam quickly...tested on Alco's plant, they raised the boiler from cold start to 300psi within 45min. In hurry seasons turnarounds were performed within 2 hours, blown down 40 min., 40 min washing, 40 min for steam and fire up.
When treated this way, I think it must be almost visible to see how the boiler grow in length while becoming hot :-)
UP 4-12-2 I suspect that being "free steaming" had more to due with the amount of available heating surface, the length of the boiler tubes, the draft, and the relative open-ness or backpressure of the exhaust. John
I suspect that being "free steaming" had more to due with the amount of available heating surface, the length of the boiler tubes, the draft, and the relative open-ness or backpressure of the exhaust.
Examples of this design included the 4-8-4 NYC Niagara and C&O J3a. The 2-8-8-4 B&O EM1 of 1945 was a very good example of a big engine using this design. The EM1 had very short, large diameter fire tubes, but had a large firebox and combustion chamber, large arch tubes, and 5 thermic syphons which gave it the same direct heating surface as the H8 Allegheny.
Those 3 engines mentioned were considered very "free steaming" and had the ability to produce high horsepower at high speeds.
Actually, the UP 4-12-2 had a rather large, long boiler and a rather large firebox. So long, in fact, they had to use a "Gaines Wall" (a low wall toward the front of the firebox) to help direct the heat where they wanted it and to have the exposed heating surface they needed (I don't fully understand the theory). It also had rather long boiler tubes. In fact--the 4-12-2 boiler is actually longer and larger than the boiler used for many articulateds (not the last designs, but many others.) The boiler was designed to stay within clearance limitations on the Union Pacific in 1926--and to stay at or near 59000 pounds axle loading--which was the UP limit at that time. A 10-drivered engine--even a larger three cylinder 4-10-2--was rejected because it could not produce the power and speed they wanted. (Note: they already had 3-cylinder 4-10-2's that did not produce enough power and speed). I think Kratville and Bush state they even considered but rejected a 4-10-4.
I'm a dumb civil engineer who designs things that don't move, but I seriously doubt that being "free steaming" had anything to do with whether an engine was articulated or not--but much more to do with the design of the boiler, firebox, superheater tubes--and yes--the smokebox--where they knew that proper installation of the deflectors had an impact on how free steaming an engine would be.
Also--the UP 4-12-2 was considered for rebuilding into a 4-6-6-2 simple articulated--which would have been built in very early 1940--but ultimately, they decided to build a 4-8-8-4 instead.
According to Kratville and Bush, installation of roller bearings on all axles would have made the 4-12-2 the "near equal" of the first group of UP challengers in actual performance. As it was, tonnage ratings on the railroad between the two classes were very similar.
I suspect that being "free steaming" had more to due with the amount of available heating surface, the length of the boiler tubes, the draft, and the relative open-ness or backpressure of the exhaust. The challengers and big boys were considered to be very "free steaming" engines.
John, Paul, et. al.,
I wonder how much of the "free steaming" ability of the 4-12-2 was due to it not being an articulated? Instead of running through long pipes with flexible joints, the supply steam would only eed s short run from the superheater output to the cylinders and conversely the exhaust steam would have had a short path from the cylinders to the nozzles underneath the stack.
With a single axle trailing truck, the UP type would have not had the firebox geometry possible with the Texas type.
Paul--
UP's studies did indicate that "freer" steaming locomotives did perform better--ie more horsepower at higher speed. They did indeed have a better draft--but that isn't all. So many of their engines were fitted with larger diameter smokestacks--or even dual stacks. Jabelman was nearly obsessed with free steaming engines and reduced backpressure. The emphasis in the west was on speed--and Santa Fe had the edge with a shorter route and higher speeds. Trains magazine, or Classic Trains, had an article about the UP 800's within the last year or two that discussed the concept of "free steaming" engines in excellent detail--better than I can.
Some boilers--like the 4-12-2's--were designed to produce copious amounts of steam--because they knew they needed it to move heavier tonnage trains faster. So they did have a reputation as very easy steaming engines--easier to get going than other types--easier to produce plenty of steam and heat. There are stories about just how easy it was to get them moving...When used in passenger service, the 4-12-2's did not have the top speed of some passenger power but they were easily able to accelerate trains rapidly out of the station stops--faster than the passenger power--and therefore were actually able to maintain passenger train schedules when called upon to do so. They were capable of speeds above 65 mph when needed.
I hope this helps some.
Respectfully submitted--
and had actually slashed operating costs (and dramatically increased average train speeds) because they steamed so much better than anything that came before them.
What does this mean that a locomotive "steamed well" or "steamed better" or was "free steaming" than some other locomotive. I have seem this term in accounts of operating and firing locomotives, but the term seems rather subjective.
Does it mean that the locomotive had high combustion efficiency, that a small amount of coal raised a lot of steam? Or does it mean that a locomotive had an effective draft system, that you could stoke the fire with a large quantity of coal to produce a lot of steam without clinkering up or choking the fire?
Was there any systematic study of designs and why a locomotive was "free steaming" and why another one wasn't?
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
Ooops,
UP4-12-2,
my bad, I did not read your mail carefully enough.
I understand Jabelman did not like roller-bearings. That he did not favor the 9000 is plausible, and valid, in my humble opinion, proved by the latter designs.
The boiler and firebox of the 3900's in fact does not diifer so much from the 9000's, though the shape became different.
They were big improvements over the elderly "Moose's" , however. Otherwise, it was up to Lima und C&O to prove, 2 cyl. and 2 rods are up to such kind of piston forces, making the third cyl. somewhat obsolete.
I meant of course 6000 indicated HP for the T1 (or 5400DBHP, if this is acceptable).
Cheers,
-edit-
BTW,
If you can think "Popular Mechanics" is a reliable source, I read there modern UP-engines had an expected life-time cycle of 3million miles or 30 years.
Jabelman decided he hated the 9000's, not roller bearings. The U.S. government was willing to pay, prior to WWII, for the upgrading of ANY steam locomotives that needed it, knowing that a big increase in rail traffic was coming. The 88 4-12-2's at that time were still the largest fleet of mainline motive power on the railroad, and had actually slashed operating costs (and dramatically increased average train speeds) because they steamed so much better than anything that came before them. The government was willing to pay for roller bearings on all axles and other improvements that would have fixed the principal maintenance issues of the 4-12-2's, but Jabelman only wanted brand new power and would not hear of upgrading older power.
I just received the book by Willian Kratville and John Bush, The Union Pacific Type, Volume 2. They did extensive, meticulously detailed interviews with actual Union Pacific employees in both the engineering and operations sections of the railroad, over a 30 year period of time, while some of the men involved in the original design and operations of the 4-12-2 were still living. These loyal Union Pacific employees made it crystal clear that Jabelman was not in favor of upgrading ANY older locomotives--but that he always believed in total replacement as being, in his opinion, more justifiable. So whenever UP management requested estimates to do this or that to improve older power, he made absolutely certain the estimates were inflated--because he wanted to build or buy new power instead.
The UP engineering department actually prepared a sketch plan to rebuild the 4-12-2's into 4-6-6-2 simple articulateds while retaining the boiler--and an estimate outside the UP engineering department was prepared. Based on that estimate, the UP management actually accepted the idea and said--"let's build the 4-6-6-2" before Jabelman stepped in and argued his case to build brand new simple articulateds instead. The sketch plan is included in the Kratville/Bush book. Ultimately, UP chose to build the Big Boys to get over 6000 horsepower instead of 4900+/- out of a 4-6-6-2.
Authors Kratville and Bush contend that if it were not for Jabelman, and the easily foreseen in 1939 coming diesel revolution, it is highly likely the 4-12-2's would have received roller bearings on all axles and some other easily doable improvements that would have upgraded them into truly first class high speed freight engines while reducing the main operational headaches. Even as it was, the UP was operating them at sustained speeds of 60 mph and above--which was hard on the frames for the ones not originally built with one-piece cast frames.
I agree the C&O 2-10-4 was a great engine, but so was the 4-12-2, and the C&O 2-10-4 did not produce 5900 horsepower--that's big simple articulated territory. So far as I'm aware the highest horsepower out of a 2-10-4 is about 5600 peak horsepower in the case of the Santa Fe 5001/5011 classes.
The 4-12-2's are recalled by those who operated them to have steamed as well or better than most engines UP ever owned, and that is why they lasted until very nearly the end of steam. Although there were maintenance issues with valve gear, they had remarkably few issues with the boilers. Even as late as 1952, after Jabelman was gone, the UP had a plan that called for keeping the last 25 4-12-2's through 1965, along with the 3900's and 4000's.
UP 4-12-2 Also--UP's 4-12-2's were never modernized with roller bearings (other than on the Gresley gear of some) becaue Otto Jabelman decided he absolutely hated them, and spent much of his career trying to get rid of them or replace them--even basically ignored potential U.S. government war-era funding for roller bearings which would have dramatically upgraded their performance and especially their durability.
Also--UP's 4-12-2's were never modernized with roller bearings (other than on the Gresley gear of some) becaue Otto Jabelman decided he absolutely hated them, and spent much of his career trying to get rid of them or replace them--even basically ignored potential U.S. government war-era funding for roller bearings which would have dramatically upgraded their performance and especially their durability.
I never read Jabelman was against roller-bearings, huh? Something mixed here with tales from Southern Pacific?
UP 4-12-2 Because they never received some "modern" improvements, we'll never know what the real potential of those engines might have been. As engine 9000 was tested in 1926, peak horsepower was 4917 indicated at the cylinders at 37 mph (reported in UP Type, Vol. I) and later improved versions most certainly did better--but there's no data regarding how much better the later versions performed. What a shame. John
Because they never received some "modern" improvements, we'll never know what the real potential of those engines might have been. As engine 9000 was tested in 1926, peak horsepower was 4917 indicated at the cylinders at 37 mph (reported in UP Type, Vol. I) and later improved versions most certainly did better--but there's no data regarding how much better the later versions performed. What a shame.
A real improvement was the T1-Texas. One Cyl. less, but a good 1000hp more than the 9000-class,
The UP got finally rid of all this 3-cyl.-maintance-horror by designing the Chally.
CSSHEGEWISCHLe Massena's problem was he often passed his uninformed opinions off as facts to the railfan community.
I was under the impression that LeMassena was more accurate and/or better informed than Lloyd Stagner. Regarding inaccuracies in printed articles and books, I became very frustrated with Lloyd Stagner's works many years ago--and refuse to buy anything that has his name on it. Why? Well, at least where Santa Fe steam is concerned, he likes to quote lots of numbers, and either his writing or the editing on the part of Morning Sun Books was shoddy. Where Stagner quotes Santa Fe steam data, especially in The Santa Fe in Color book series, there appear to be several mis-quotes. This does not become fully apparent until you read the cited sources (S. Kip Farrington's The Santa Fe's Big Three, which included many actual Santa Fe loco test reports). Always go back to the original data source and be wary of locomotive horsepower and/or tractive effort ratings in print. Recent Classic Trains Steam special issues have also included articles that appear to conflict with each other where locomotive data is concerned.
This thread makes very interesting reading, especially for someone like myself who has read LeMassena's Articulated Steam Locomotives of North America books...
Regarding great, or potentially great engines, or relatively unsung engines:
The Santa Fe hudsons were known for beinq quite slippery, and in that regard are not as fondly remembered by most SF fans as the 4-8-4's.
The 5001 and 5011-class Santa Fe 2-10-4's were marvelous engines producing very high horsepower (if I recall correctly, well above 5000 horsepower for a 30 mph band of usable speed according to the actual test data published in S. Kip Farrington's The Santa Fe's Big Three.) but because they toiled mostly in the New Mexico desert, they are largely forgotten. In the curvy areas of Arizona, the 2-10-2's apparently performed better--so I think many folks forget about or vastly under-rate the 2-10-4's.
Also--UP's 4-12-2's were never modernized with roller bearings (other than on the Gresley gear of some) becaue Otto Jabelman decided he absolutely hated them, and spent much of his career trying to get rid of them or replace them--even basically ignored potential U.S. government war-era funding for roller bearings which would have dramatically upgraded their performance and especially their durability. Because they never received some "modern" improvements, we'll never know what the real potential of those engines might have been. As engine 9000 was tested in 1926, peak horsepower was 4917 indicated at the cylinders at 37 mph (reported in UP Type, Vol. I) and later improved versions most certainly did better--but there's no data regarding how much better the later versions performed. What a shame.
I wish to defend both the Lima A-1 2-8-4's on the Boston and Albany and their near cousins with Coffeen fedwater heaters ("the John L. Lewis look") on the nearby B&N. Both did their jobs, Both crossings of the Birkshire Moutains were early candidates for dieselization, but not because of any problems with the Birkshires. The B&A's did see further use on the NYC system and were seen later in Michigan, Ohio, Illinois, and Indiana, often with larger tenders. And obviously the AT&SF thought enough of the B&M's to buy some.
That does not prevent from admiring the NKP-PM-W&LE-C&O design even more.
GP40-2CSSHEGEWISCHWhile Le Massena concedes that the design of NP's power took consideration of the low-grade coal that was available, he implied that even better performance would have been possible with good coal. Better performance would have been possible with better coal AND a complete redesign of the combustion area. It is not as simple as just using better grade coal in the existing design. Railroads that had the best steam coal in their backyard such as the N&W, C&O, and B&O had their boilers, specifically the firebox/combustion chamber area specifically designed to maximize the potential of such coal. Same with powerplant design. You can't take a plant that was designed to used Powder River coal, and start using fast burning/high BTU Pittsburgh Grade coal. The entire combustion area would need to be redesigned. Le Massena problem was he often passed his uninformed opinions off as facts to the railfan community.
CSSHEGEWISCHWhile Le Massena concedes that the design of NP's power took consideration of the low-grade coal that was available, he implied that even better performance would have been possible with good coal.
While Le Massena concedes that the design of NP's power took consideration of the low-grade coal that was available, he implied that even better performance would have been possible with good coal.
To start with, is there a point where a large grate with high-BTU coal might melt the crown sheet?
Would the flues be sufficient to carry off the hot gases from the firebox-combustion chamber?
Would superheaters be large enough for adequate steam flow?
Would the firebox-combustion chamber and flues absorb that heat for steam production efficiently?
Finally, would these improvements reach peak output at 40 mph, about the limit for 63" drivers; or would the engines be considered "slippery!"
The Red Lodge mines were gassy. The geology wasn't very fun, either.
RWM
Railway ManColstrip was a very advanced mechanized mine for its time, and of great interest just for its very low mining costs.
Colstrip was a very advanced mechanized mine for its time, and of great interest just for its very low mining costs.
The 9 cu. yd. dragline that was part of the original opening of the mine ca 1923, was still in use in 1971 along with the "small" electric shovel (ISTR also about 9 cu. yd.).
Prior to opening the mine in Colstrip, the NP was getting its coal from the mines around Red Lodge. The Red Lodge mines were underground and thus labor intensive, which was particularly important after the wage inflation due to WW1. Another issue was safety, the worst mining disaster in Montana history was happened in Bear Creek (a very few miles east of Red Lodge) during WW2.
CZ:
The source of coal for the NP Yellowstones (as well as many other NP steam engines in the Rocky Mountain area) was the company's open-cast mine near the town of Colstrip, Montana. Popularly referred to at the time (and in railfan legend) as lignite, this is in fact a sub-bituminous coal of about 8,300 BTU. Today, we call this "Northern Powder River Basin" coal and it is mined from the exact same seam for large mine-mouth power plants owned by Colstrip Energy and Pacific Power & Light, and for numerous northern plains and Midwestern utilities such as Detroit Edison.
NP's coal supply west of the Rocky Mountains was the company mines at Roslyn, Washington.
Most railways that served major coal-producing regions owned their own coal mines and sourced as much coal as possible from their captive mines. Some of these coal companies bore the same name as the railroad (e.g., Union Pacific Coal Company) and some did not (e.g., Utah Fuel Co. of the D&RGW; Clearfield Coal Co. of the NYC).
The NP's use of the very large firebox on the Yellowstone was an attempt to gain better efficiency from the low-value coal it had close at hand in Montana, as opposed to higher heating value coal from Roslyn, the Illinois Basin, or "Lake Coal" via Duluth, which was considerably more expensive due to transportation costs to carry it to Montana to put into a locomotive tender. Both Railway Age and Coal Age covered the NP's effort extensively as it was of great interest to both the railway and coal industries, the former hopeful that it would be technically possible to burn such poor-quality coal and still generate adequate transportation without high maintenance and locomotive failure expense; the latter hopeful that it would create a market for otherwise worthless coal in an era when oil and natural gas were rapidly encroaching on the railway, domestic, and industrial heating and process market. Colstrip was a very advanced mechanized mine for its time, and of great interest just for its very low mining costs.
feltonhill The NP 2-8-8-4's grate area was initially 182 SF, but it was later reduced to 161.4 SF because of drafting/combustion problems.
The NP 2-8-8-4's grate area was initially 182 SF, but it was later reduced to 161.4 SF because of drafting/combustion problems.
The grate size was to burn the (Rosebud) coal, which was a very poor but cheap grade of coal. The Z5 was not a high capacity type of locomotive and was used in pusher service almost entirely after the Z6, Z7 and Z8's were running. The Z5 was very large at the time it was built, but a very slow locomotive compared to the Z8's or the Big Boys. I am not sure about the exact name of the coal, but it was cheap and so the NP engines grate size had to be much larger to get proper amount of heat out of it.
CZ
feltonhillThe best I have is that it weighted 405,600 lbs, excluding tender.
IC #1 was 388000 lbs, excluding tender. It was the only attempt at a freight Hudson, but was too slippery.
C&NW, CA&E, MILW, CGW and IC fan
I was underwhelmed when I first read about this method of power ranking, and the more I thought about it, the more exceptions I could find, even when I held the caloric value of coal constant. (This thread's discussion of BTU values has been very useful to explore a different area of disagreement.)
A central problem was the dismissal of the boiler. Same grate, same pressure and I was pretty sure you'd have different results with different-sized boilers.
Then I wondered about the effect of superheating the steam that's produced? So I used the "equivalent heating surface" calculation of 1.5 x the superheater's sq footage divided into the total heating surface. That brings the boiler into play and, as I'll show in a moment, takes a long step toward making this a useful way to compare locomotives.
But then I thought of oil-fired locomotives - they don't have "grates" in the sense of spreading the fuel out over a single surface. They burn their fuel in a volume bounded by the firebox. So I substituted firebox heating surface for grate area, which I think allows for an apples-to-apples comparison of oil burners with coal burners.
And, I thought, if grate area is your only measure, then clearly Wootten anthracite-burning fireboxes take the palm. Their grates are relatively huge - at least twice the area and often more compared to an equivalent narrow-firebox design. What I discovered is that these fireboxes usually had very similar direct heating surface areas, so soft-draft, thin-fire apparatuses such as these can be compared.
After tinkering some more, I came up with a formula that takes into account the superheater's contribution as outlined above,
the higher rates of evaporation per square foot of heating surface for fireboxes compared to tubes (about 6 to 1),
driver diameter (fewer RPM means fewer "lungfuls" per minute or per mile).
It was a lot of fun and the resulting number works pretty well for all kinds of steam locomotives. But along the way, I became satisfied that using firebox (or direct) heating surface area (this includes syphons, arch tubes, combustion chambers...) times the boiler pressure times the superheater ratio(x 1.5) can give a shorthand comparison.
Steve Llanso, Locobase.
More quotes from the article--
"The [CB&Q] 2-10-4 was operated at speeds well below that for peak power (about 20 mph)...The Burlington 2-10-4's big boiler, 107-square-foot grate, and 250-pound pressure, thus misapplied, were more ornamental than useful in the production of ton-miles at minimum cost."
CB&Q got the 2-10-4s to haul 8000-ton coal trains out of southern Illinois; ruling grade against the loads may have been 0.3%, which would indeed slow them to 20 mph or so-- when they were on that grade. But most of the time they wouldn't be on that grade, so most of the time they'd be making better speed, maybe even good enough to satisfy Le Massena. No doubt he'd prefer that they reduce the assigned tonnage, but he still makes no attempt to explain how that would lower costs."When the [SP] cab-forwards were used in passenger service over difficult profiles at high speeds, their performance was magnificent; yet their primary use was in low-speed freight service, three or four to a train, operating well below the ultimate capacity of boiler and machinery."
In the 1940s SP rated its newest 4-8+8-2s at 1450 tons eastward over Donner Pass, with which they could apparently make 15 mph or better on the steepest part of the climb. Not good enough for Le Massena-- one wonders what tonnage rating he would have approved. Note that if they cut trailing tonnage by, say, 40%, they'd only be cutting total tonnage by 30%, so the increase in ton-miles per hour won't be that great.
As a follow-up, I see you gave a weight for the A-1 of about 393,000 lbs. That would put approximately 59,000 lbs on the lead truck (29,500 lb axle load) and 118,000 lbs on the trailing truck (59,000 lb axle load) with a 2:1 ratio. A 3:2 ratio would result in 35,400 lb and 53,100 lb axle loads on the respective lead and trailing trucks.
Didn't the IC engines get cast steel beds and cylinders when rebuilt?
The IC 4-6-4 weight would be very close to that of the NYC A-1 2-8-4. It's a matter of weight redistribution, moving the driving wheels forward, in part because of their larger diameter. My guess is that the IC engine had 216,000 lbs on the drivers, 2/3rd of the difference on the trailing truck and the remainder on the lead truck.
I never could figure out where the "total" weight figure for IC's 4-6-4 came from in the article. The best I have is that it weighted 405,600 lbs, excluding tender. The predecessor 2-8-4 weighed 393,500 lbs, also excluding tender. Typo? Maybe, but I doubt it was an intentional "gotcha" figure. If anyone has ever checked the complete table in the Trains article, there are several inaccuracies, perhaps due to rounding or other causes. I never found them until PC's came into play in the 1980s and I could put the entire table into one spreadsheet very quickly.
AFAIK, Santa Fe had 10 early-design 2-8-4's purchased from B&M - 4101-4104 and 4193-4198. These weren't extended mikados.
timzbeaulieu the Lima design is typified by the NYC A-1 class (and used also by IC and ATSF) doesn't seem to have been as successful as the design created by the "Advisory Mechanical Committee" (Van Sweringen roads).Railfan books/articles like the later engines better, and limited cutoff sure went out of fashion after 1930 (except on SFe). Aside from that, what do we know about their success?
beaulieu the Lima design is typified by the NYC A-1 class (and used also by IC and ATSF) doesn't seem to have been as successful as the design created by the "Advisory Mechanical Committee" (Van Sweringen roads).
Railfan books/articles like the later engines better, and limited cutoff sure went out of fashion after 1930 (except on SFe). Aside from that, what do we know about their success?
I meant to correct the reference to Santa Fe Berkshires and change it to Missouri Pacific. The Santa Fe's Berkshires were just enlarged Mikados. The Lima designed Berkshires on NYC's B & A amounted to 55 locomotives in one order. They were never duplicated, and were replaced by diesels fairly soon after WW2. Both Missouri Pacific and Illinois Central rebuilt their fleets of Berkshires to totally different types of locomotives, which clearly indicates that they were unsatisfactory as built.
Lars Locois this correct, as I may understand you, he made mistakes on purpose? Maybe it was just a typo?
"The year 1937 represents the high-water mark of steam locomotive development and construction. During the previous two decades power-producing capabilities had doubled; of vastly greater significance was the fact that power per ton of locomotive weight had also virtually doubled. One specific example is revealed by comparing the latest Santa Fe 4-6-4 (300 pounds pressure, 99 square feet of grate, 412,000 pounds total weight) with Illinois Central's 4-6-4 conversion from Lima's A1 model (265 pounds pressure, 100 square feet of grate, 692,000 pounds total weight)."
Could he really have thought he was comparing engine weights?
timz"Lima Locomotive Works, however, was not in agreement with this method of railroading; its 1925 experimental 2-8-4 with large boiler, big grate area, small cylinders, and bigger drivers was designed to deliver its maximum power at higher speeds. Excellent over-the-road performance was in direct opposition to the prevalent maximum-tonnage, minimum-speed gospel of current popularity. Despite the 2-8-4's immediate success, any number of tonnage worshipers refused to accept the new doctrine of speed first, tonnage second." The new doctrine, fortunately conceived by Lima. But I'm guessing Lima wasn't trying to force any new doctrines on the railroads-- they were in the business of selling locomotives, and the way to do that is to build locomotives that do the job the railroad wants done. They intended the 2-8-4 to pull the same drag tonnage as a 2-8-2 while burning less fuel at drag speed and making better speed once past the ruling grade. Some railroads would have "fast freights", and the 2-8-4 was intended to be well suited to them too-- but Lima didn't ask the railroads to reduce train tonnage, on the "fast" freights or the drags. The 2-8-4 wasn't actually "designed to deliver its maximum power at higher speeds". It was designed to deliver higher power, which would inevitably be at a higher speed than on the older engine. Maybe the old engine was good for 2500 dbhp at 25 mph and the 2-8-4 could do 3500 at 35 mph-- that's great, but if Lima could have found a way to get the 2-8-4 to do 3500 dbhp at 25 mph they would have jumped at the chance.
"Lima Locomotive Works, however, was not in agreement with this method of railroading; its 1925 experimental 2-8-4 with large boiler, big grate area, small cylinders, and bigger drivers was designed to deliver its maximum power at higher speeds. Excellent over-the-road performance was in direct opposition to the prevalent maximum-tonnage, minimum-speed gospel of current popularity. Despite the 2-8-4's immediate success, any number of tonnage worshipers refused to accept the new doctrine of speed first, tonnage second."
The new doctrine, fortunately conceived by Lima. But I'm guessing Lima wasn't trying to force any new doctrines on the railroads-- they were in the business of selling locomotives, and the way to do that is to build locomotives that do the job the railroad wants done. They intended the 2-8-4 to pull the same drag tonnage as a 2-8-2 while burning less fuel at drag speed and making better speed once past the ruling grade. Some railroads would have "fast freights", and the 2-8-4 was intended to be well suited to them too-- but Lima didn't ask the railroads to reduce train tonnage, on the "fast" freights or the drags.
The 2-8-4 wasn't actually "designed to deliver its maximum power at higher speeds". It was designed to deliver higher power, which would inevitably be at a higher speed than on the older engine. Maybe the old engine was good for 2500 dbhp at 25 mph and the 2-8-4 could do 3500 at 35 mph-- that's great, but if Lima could have found a way to get the 2-8-4 to do 3500 dbhp at 25 mph they would have jumped at the chance.
Timz, the Lima design is typified by the NYC A-1 class (and used also by IC and ATSF) doesn't seem to have been as successful as the design created by the "Advisory Mechanical Committee" (Van Sweringen roads). The Lima design used larger cylinders and 63" Driving Wheels, and used Limited Cutoff to keep TE within reasonable adhesion limits. The design featuring smaller cylinders combined with reasonable boiler pressure originated with the AMC rather than Lima. The first AMC designed Berkshires were the Erie S-1design built by Alco-Brooks. Lima built the S-2 and S-4 batches, while Baldwin built the S-3 batch, these locomotives introduced the larger diameter Drivers to the Berkshire design which had previously used 63" drivers like many Mikados. The design was then refined into the classic NKP S-1 Berkshires with a more balanced, smaller cylinder and longer stroke, cmbined with a larger Driving Wheel diameter design.
timz Say we're deciding what tonnage to give to our new 2-8-4s on a railroad where the ruling grade isn't too tough-- 0.5 %, let's say. We try a 3500-ton train and the engine makes the grade at 12 mph; we try a 2500-ton train and it does 25 mph over the summit. If we assign 2500 tons instead of 3500 our ton-miles per train-hour on the grade will be 49% greater. Far as we can tell from his article, Le Massena takes it for granted that more ton-miles per train-hour means lower total cost to run the railroad. Better service for the shippers and lower costs-- what's not to like? Seems simple enough, doesn't it? But not simple enough for lots of railroads, who unaccountably persisted in assigning 3500 tons to their 2-8-4s. Le Massena's conclusion: railroads were run by blockheads. I can't blame you for assuming I must be setting up a straw man-- surely he couldn't be that serenely obtuse? And maybe he can't be-- but the article gives no hint of any analysis beyond the seeming parody given here. More quotes to follow.
Say we're deciding what tonnage to give to our new 2-8-4s on a railroad where the ruling grade isn't too tough-- 0.5 %, let's say. We try a 3500-ton train and the engine makes the grade at 12 mph; we try a 2500-ton train and it does 25 mph over the summit. If we assign 2500 tons instead of 3500 our ton-miles per train-hour on the grade will be 49% greater.
Far as we can tell from his article, Le Massena takes it for granted that more ton-miles per train-hour means lower total cost to run the railroad. Better service for the shippers and lower costs-- what's not to like?
Seems simple enough, doesn't it? But not simple enough for lots of railroads, who unaccountably persisted in assigning 3500 tons to their 2-8-4s. Le Massena's conclusion: railroads were run by blockheads.
I can't blame you for assuming I must be setting up a straw man-- surely he couldn't be that serenely obtuse? And maybe he can't be-- but the article gives no hint of any analysis beyond the seeming parody given here. More quotes to follow.
I do not have the article, maybe he meant running it hours for hours just on a grade, the higher HP-engine is no bonus, there.
Dear Tim,
timz Some will ask: if it's true he made such an obvious error, why haven't the legions of razor-sharp railfan nitpickers mentioned it? Well, on page 41 he favorably compares the SFe 3460-class (412,000 lb "total weight") to an IC 4-6-4 (692,000 lb "total weight"). Presumably he didn't really think the IC had a 4-6-4 nearly 70% heavier than the hulking SFe engine-- he must have thrown that in to see if people were paying attention. Far as we can tell from the letters in Trains, no one was. He must have been appalled. More to follow.
Some will ask: if it's true he made such an obvious error, why haven't the legions of razor-sharp railfan nitpickers mentioned it? Well, on page 41 he favorably compares the SFe 3460-class (412,000 lb "total weight") to an IC 4-6-4 (692,000 lb "total weight"). Presumably he didn't really think the IC had a 4-6-4 nearly 70% heavier than the hulking SFe engine-- he must have thrown that in to see if people were paying attention. Far as we can tell from the letters in Trains, no one was. He must have been appalled.
More to follow.
is this correct, as I may understand you, he made mistakes on purpose? Maybe it was just a typo?
Would a measure of current fixed utility power plant's boiler pressure give a good balance of higher pressure vs more complex piping??
I don't have access to Railway Engineering (Hay), but I do remember rated boiler horsepower factors in grate area, direct heating surface, firebox and flues, indirect, superheater steam tubes in the flues, and boiler pressure. I think a factor for bituminous coal was assumed. It seemed the efficiency was measured as the proportion between pressure in the boiler and in the piston having a lot to do with steam flow. FYI, I calculated that a fairly large, later series C&NW E-Class Pacific put out about 2,500hp.
The grate area alone would yield different results than for boiler power; and La Massena had an argument for discounting the other factors in his rating system.
So Le Massena calculated the "potential power" (pressure time grate area) for a bunch of engines, along with their "power" per ton of engine weight, which was his criterion of merit. Since in his view merit was roughly proportional to boiler pressure, his favorite engines couldn't have much less than 300 psi. The SFe 3460-class 4-6-4, 3765-class 4-8-4 and 5001-class 2-10-4 all had 300 or more, and they all were at least tied for largest grate area of their type (except for the NP dirtburner 4-8-4s, which used lower pressure). So he concluded "AT&SF was the uncontested leader in three-, four-, and five-driving-axle locomotives of conventional design." Uncontested! Nobody can accuse the guy of being afraid to stick his neck out. His locomotive ratings didn't seem to make much impression, but his railroad ratings have stuck pretty well-- they're now conventional wisdom, unfortunately. Like lots of fans he figured the railroads would do better if they'd just run their trains faster: "Meanwhile, however, a few railroads were relying more on speed than on tonnage to give themselves better operating statistics while supplying better service to their shippers. Among these heretics were Nickel Plate, St. Louis Southwestern, Santa Fe and Union Pacific." "Like the Santa Fe and unlike many other roads which misapplied their high-power engines, UP held down tonnages, allowing its locomotives to run at high speeds and thus deriving from them the most work in the least time at the least cost. The financial records of these carriers are convincing evidence of their unorthodox operational philosophy."
They got better stats and lower costs by being heretical and unorthodox... we need details on that. They will follow.
The quality of the coal as fuel definitely had an effect. The NP Yellowstones had their enormous fireboxes because they were designed to get the most of the low-grade coal that they burned. Lloyd Arkinstall, in one of his articles about firing for PRR in New Jersey, commented on the difference between the Westmoreland County coal supplied to passenger power and the West Virginia clinker coal he was stuck with on his local freight.
The question that I wanted to ask was referencing the Quality of Coal Burned in the various steam locomotives. By no means am I a technical person, so I may be overly simplistic, but it seems to me that the Quantity of coal, plus draft, and combustion creat the BTU's needed; the quality of the available coal to be combusted would be a consideration in the final performance delivered. and the one thing missing from these conversations as well as the ones on the previous link is exactly the bearing of coal quality on the equations.
reference from this link: http://geology.about.com/od/mineral_resources/a/aa_nutshellcoal.htm
The UP's Big Boys, as I understand it were designed to burn a lower grade of Wyoming coal. The Allegeheny was designed to burn various grades of Appalachian coal ( either Bituminous or Anthracite?). Illinois Central burned available coal from Illinois mines and Kentucky mines ( my guess it was bituminous, but I am unsure about its quality). The Katy, as I had said burned a local coal from company mines in Kansas ( it was poor quality but readily available.) Santa Fe utilized oil, and may also as well used coal for fuel (not completely sure about that) ?
My questyion is would not the quality of fuel burned, be a factor in the functioning of grate size and the individual locomotives steaming ability ?
The article kind of made sense when I first read it at the end of 8th grade, but less so after taking a engineering thermodynamics class in my senior year in college.
Just for grins, I dug out my thermo textbook and looked up the steam tables - assuming isentropic performance from an engine, one could get maybe 30% more power out of steam at 500psi & 700F versus 240psi & 700F. This implies that a more accurate formula would have been grate area times pressure to (say) 0.4 power.
Our community is FREE to join. To participate you must either login or register for an account.