True -- if the train is more than 11600 tons, speed with two H-8s will be less than 18 mph, on 0.57%.
nhrandI don't have drawbar horsepower vs speed curves handy for the H-8 but I do have curves for the N&W Class A 2-6-6-4 and the Y6b 2-8-8-2 handy and they give an approximation of what could be expected if the C&O stayed with a 2-8-8-2.
This is cute, but manifestly silly. The 'correct' comparison for C&O is not to the Y6 as built -- which, you will notice, is not what I proposed for a compound locomotive at all -- but the simple-expansion Y7, on which enough preliminary detail design was done to have a good idea of the principal numbers. If the source you used for your posted numbers was Ed King's book on the A, you will find a short section on the Y7 right there for your perusal.
Obviously C&O wouldn't be bothered with anything the size or style of the H7 articulateds -- those were passe by the time trials on the T-1s were complete. I have to suspect that some of the careful consideration they gave the Q-2 involved the possibility of a similar rigid-frame 'bettering' of the HP of what, in the Allegheny, was a large, incredibly complicated, heavy locomotive -- I have to wonder what might have happened had PRR sent a locomotive in good condition, with enthusiastic support people, for the testing.
Note again that the modifications necessary for the 2-8-8-2 involve careful use of mechanism that equalizes the thrusts of the cylinders and, where possible, the inertial masses, so the engine responds as a simple articulated would, and the refinement of the chassis to use class A or Challenger-style restriction of vertical hinging within the limits of (possibly-enhanced) equalization and vertical suspension travel. While of course I have no actual test data on this, it is very clear that the falloff in Y-class efficiency due to 'compounding' does not apply to the Chapelon-converted engine, just as I suspect it would apply much less to the engines with 'booster valves' than those producing the statistics you quoted. Again, the reason to retain compounding on an engine for C&O would be to reduce the water rate (and the other associated factors) and thereby increase things like effective range; something that needs to be considered is whether C&O, which notably used a very conservative pressure on the Alleghenies, would embrace a 'culture' of 300 to 315psi boiler construction and maintenance, as was becoming something of a 'fad' in the last days of advanced big steam design here.
But of course, if they didn't want to optimize for compounding, they could just adapt the Y7 to their taste, and have something dramatically better suited for most of their actual operation than an Allegheny.
Mind you, this says nothing, and is intended to say nothing, about any performance on test trains. It's cute to point out that N&W 610 happily ran at 110mph 'in testing'; whether N&W actually ran it at that speed for any particular percentage of its actual service time is far less likely. As is the extended question of Allegheny performance: perhaps they could accelerate heavy trains to higher road speed and then happily use their (quite good) developed HP at speed to hold them there. But the fact remains that C&O wasn't running a one-speed railroad at that speed, and the moment they decided to run trains at 'convenient' or 'economic' slower speed to any extent -- and the historical record clearly and repeatedly confirms that is what C&O chose to do -- they would have been better off with a design optimized for that reality (provided that it could fulfil any actual higher-speed duties competently when required ... which both the Y7 and modified Y6 would have done).
To Overmond:
Could have, should have discussions can be interesting but inconclusive. I admit to being defensive about the Alleghenies, and maybe more than I should. Actually, I never saw an Allegheny in steam but spent time on the N&W when A's and Y-6's were the main freight power. Maybe I like the Allegheny simply because I can go to the B&O Museum and sit in the engineer's seat of the preserved H-8 and daydream.
Yes, the C&O might have gotten more out of a modern, single-expansion 2-8-8-2 similar to the Y-7 the N&W had in mind or some other advanced design. Maybe a 2-8-8-4 should have been considered. Would such a design have been cheaper to buy and less expensive to operate and maintain ? I don't know. But I do suspect that the C&O would not have been significantly more satisfied with a 2-8-8-2, a 2-8-8-4, more 2-10-4's, etc. I still think the H-8 2-6-6-6 was more flexible and there were many, many trains that the H-8 handled well that would not have been handled as well by a 2-8-8-2 -- I'm thinking of the many mixed freight or passenger assignments where speed and power were useful. Certainly, managing a dual-service stable can definetly be inefficient at times and too much time may have been spent on heavy coal trains. Plus, it is obvious that a motive power decision made at the eve of World War II would not necessarily be the best one in less than a decade later. Operating needs change or new people have different ideas about how to use motive power.
I still would like someone to tell me why so much very expensive diesel horsepower is used on freight movements that I suspect could do well with less. That should be easier to answer than whether an Allegheny was the wrong engine for the C&O.
Mr. Rand, you got to sit in the engineer's seat of the B&O Museum's Allegheny?
How'd you manage that?
The last time I saw it the cab was swarming with kids! It looked like a playground gone berserk!
Hey, I didn't mind. We have to generate the next generation of railfans somehow!
It's probably just as well I couldn't get in the cab of the Jersey Central 1000 either, (nobody can) I'd have gotten in trouble trying to start it. It still smells like diesel fuel.
nhrandI admit to being defensive about the Alleghenies, and maybe more than I should.
Don't be ashamed or even worried about advocacy -- anything I might say would have to apply just as equally to fervent advocacy as to a less passionate view. And remember that I still admire the Alleghenies as an effort to build fast modern power at the effective limits of contemporary reciprocating-engine practice -- something at which the design largely succeeded.
Maybe a 2-8-8-4 should have been considered. Would such a design have been cheaper to buy and less expensive to operate and maintain?
Probably not. Most of the 2-8-8-4s that were built were intended more as 'drag' engines than fast power: one might include a 2-8-8-4 version of a Big-Boy-sized locomotive with appropriate running gear and clearances, but to my knowledge no such thing was actively considered; the B&O EM-1s are a potential competitor, but more in the principle than the reality, as B&O's clearances and permissible loads were far below what C&O could 'optimize'.
But we immediately note that any deep-firebox eight-coupled engine that would nominally 'replace' an Allegheny would be larger, longer, and probably heavier than an Allegheny, and therefore more expensive to build and perhaps more restrictive of consist length. I would presume that a C&O version of such a thing would have the same leading-truck arrangement as the Alleghenies, and would be easily able to accommodate a double-Belpaire chamber (by the time Lima had worked around to touting the things) on whatever the effective driver size for it would be ... this being one of the critical design considerations. There will be a 'sweet spot' largely determined by rod inertia, balance considerations, and TE at speed that will fix the design driver diameter (net of largest tire diameter after servicing, but tolerant of what might be substantial wear and returning before replacement) and I would hazard a rough guess that no less than 63" drivers, and likely cast centers in at least the mains, would be appropriate to give true higher 'expected' peak and average speed when actually permitted to make at least part of a given run at higher track speed.
Theoretically an eight-coupled engine with lower drivers could, by 1941 or so, be balanced to fast-freight speed. An N&W Y-class just out of the shops could very famously be run downhill at fairly dramatic speed ... but it doesn't take much deep thought to understand that doing so with any kind of regularity would not help long-term reliability even with the very best of the 'best practice' maintenance N&W could provide, let alone what C&O was prepared to do.
... I do suspect that the C&O would not have been significantly more satisfied with a 2-8-8-2, a 2-8-8-4, more 2-10-4's, etc.
Any WPB-style 'required' construction of an existing 2-8-8-2 or 2-8-8-4: as Curly might say, 'Soytinly". Any greater construction or 'expansion' of 2-10-4s (as PRR very effectively did with their T-1 "clones" once they figured out the redlining situation) was relatively unlikely to come up to the standards of the Alleghenies, which were specifically designed as 'enlarging' follow-on power to the T-1s just as the T-1 was an improvement on earlier large power (most notably, simple-articulated 2-8-8-2s of contemporary design).
At this point we could briefly consider again whether C&O would find the idea of a higher-nominal-power duplex locomotive, like a 'revised' Q2 with the original bugs worked out of it, as preferable to an Allegheny as the T-1 was preferable to the H-7s. This is in my opinion less of a shoulda-woulda-coulda analysis than any of the 2-8-8-x "opportunities", as there is little doubt that a good duplex with comparable leading dimensions to an Allegheny but dramatically shorter overall length and better construction simplicity could do the job ... except with the necessary presence of a four-coupled engine and the associated need for really good autonomic slip protection at all achievable speed ranges. Maintenance costs probably comparable to an Allegheny as far as cylinders and valve gear were concerned; how much fun you'd have by eliminating all the flexible joints and necessary steam-flow bends for the hinged forward engine would have to be determined from C&O's actual maintenance data. People will try to whine about long rigid wheelbase, but that's not a very real issue, particularly as it was less even for a Q2 with 69" 'maximum-diameter' drivers than for a Santa Fe 5001/5011 class. And there can be little argument that the augment from the duplex, even if Deem-conjugated, would be lower than even the best equivalent to the last N&W As C&O could have built or specified (with lightweight Timken rods and running gear). This becomes more relevant when thinking about...
I still think the H-8 2-6-6-6 was more flexible and there were many, many trains that the H-8 handled well that would not have been handled as well by a 2-8-8-2 -- I'm thinking of the many mixed freight or passenger assignments where speed and power were useful.
I'd be very interested to see non-wartime examples where C&O ran Alleghenies to 'full effect' -- that specifically includes M&E trains. I personally suspect that the track forces involved in operating a locomotive as heavy as an Allegheny in truly fast -- let's call it above the 70mph that N&W As apparently routinely could run at -- service would produce more problems than the revenue from the service would justify, but I'm not sure we need to go that far: we need to consider whether a locomotive with the characteristics of a Y7 configuration improved up to reasonable state of the art in 1941 would have enough upper-end performance to fulfil whatever high speed C&O needed out of a large single engine, and not one or two 2-8-4s, which is something that Dave Stephenson could probably address with some direct reference to hard data on C&O traffic. This while significantly optimizing both the fuel and water consumption and maintenance issues attendant on loading the H-8s down where their actual advantages wouldn't be realized for all the regular miles where the 2-8-8-x has distinctive competence.
Certainly, managing a dual-service stable can definitely be inefficient at times and too much time may have been spent on heavy coal trains. Plus, it is obvious that a motive power decision made at the eve of World War II would not necessarily be the best one in less than a decade later.
The key to the whole point of the discussion is to develop a 'dual-service stable' that actually optimizes performance toward the way the locomotives would be typically used in actual service. (Any competent series of test runs would include at least a few that legitimately did this, rather than 'seeing what the locomotive could do' under ideal conditions for its design assumptions.)
There's no intrinsic reason a good eight-coupled articulated with 2-wheel leading truck need be any more 'unstable' than a comparable Berk up to the highest speed the latter could achieve, other than some considerations regarding Cooper rating and longitudinal track loading that probably wouldn't apply with any relevance to C&O (as the Allegheny's peak load would be greater than either a brace of Berks or the 2-8-8-x equivalent.) Now, we have some admittedly somewhat anecdotal claims about what that is for 'fully-comparable' AMC Berk designs; Ross Rowland in particular is likely to have some interesting peak numbers (and corresponding readings on the superheat gauge) for you.
Yes, to an extent this depends on 'line changes' later than 1941, but these were well-recognized as they developed in importance in the immediate postwar period, and very little if anything of full importance radically postdates, let's say 1950 (the date the Cunningham circulation equipment was patented in Canada) and would of course be available to re-fit on Alleghenies just as on any other contemporary locomotive. Certainly there is little if any mechanical complexity in Chapelon proportional IP injection that Forties-era technology couldn't achieve (it is certainly much easier now, but that doesn't count in part for the reasons you mention).
Operating needs change or new people have different ideas about how to use motive power.
I will immediately acknowledge something you as an advocate should probably remember and adopt: the Alleghenies were IMMEDIATELY relevant in many senses to C&O traffic and priorities from the date they were constructed through to some reasonable point in 1945 that effective wartime traffic dropped off. They may well have become relevant in some of the same ways again during the Korean 'incident' (where long main trains again became prioritized along with the likely desire to 'get them over the road and out of traffic ASAP'...
There are certainly documented examples of people making mistakes how to use their power (PRR, for example, has many in a variety of respects) and in any case it's the 'right' of the owner to run things "sub-optimally" if in their sole judgment it works better for their purposes. Again, the argument here is whether a different detail design of locomotive would have served C&O better, for C&O's purposes in ways C&O management or even ownership would acknowledge as 'better'. And in my opinion advocacy for a given locomotive or even wheel arrangement 'ought' to be given a bit less emphasis at least while investigating what the bounds of that argument will be. That's not intended as a criticism either of you or your love for the Allegheny design.
I don't think there is just 'one true' reason why that is done -- it might involve protection against road failure, or tolerance of poor maintenance priorities, or 'snapping' of speed at certain points in a run, or power balancing, to name a couple off the top of my head. Periodically I see a single 4400hp engine assigned to a long string of largely-empty articulated stack sets or empty autoracks ... then I don't see any such thing for months. Whether this actually reflects anything, I of course can't say with any assurance.
Remember in any case that the concept of 'ruling grade' applies to over-the-road power-desk assignment, as does a consideration of how weather conditions (either known or 'accidentally' evolving) might adversely affect any point of the run. There are a number of experts on here who can, either in direct post or PM, tell you everything you want to know about effective real-world power management.
And I want to leave you with the idea that the issue is less that the Allegheny was a 'wrong' engine for C&O than it is that some other types of engine might have been 'righter' for them. None of this, even practical success of the M-1 turbines, would have changed the fundamental reasons C&O abandoned any kind of external combustion. They had the clear opportunity to purchase TE-1 variants ... or have them built by other builders ... and I think history speaks for itself on how that went. So I think it likely there would be little, if any, little 'difference' in the longevity or perceived worth of C&O steam if one of the alternative forms of reciprocating power had been built, either in 1941 or 1947, instead of the Allegheny.
One has to remember that the C&O was more of a railroad than just getting coal in large quantities over the Alleghenys from the mines to the Tidewater - and over a lot of those territories the 2-6-6-6's handled large trains at speed
Never too old to have a happy childhood!
BaltACD ... over a lot of those territories the 2-6-6-6's handled large trains at speed
What speed -- both peak and average? What rate of acceleration from internal signal 'checks' and other kinds of slowdown? These are important to establish with reasonably good data.
nhrandI still would like someone to tell me why so much very expensive diesel horsepower is used on freight movements that I suspect could do well with less.
.
The 2-6-6-6 appears to be the ONLY articulated that had a boiler that required a trailing truck--the bottom of the firebox was substantially below the tops of the drivers. All other articulateds had fireboxes that extended over the drivers, and had to vertically allow for their height.
I find that design difference interesting.
One could argue that, if the bottom of the firebox had to be high to clear the drivers, then why not replace the trailing truck with more drivers. I assume that that would have used too much steam at higher speeds. So the trailing trucks were used as weight-bearing devices, not because the firebox demanded them.
I'll add that a two-wheel trailing truck might have also been useful in aiding locomotive tracking at speed.
Ed
7j43kThe 2-6-6-6 appears to be the ONLY articulated that had a boiler that required a trailing truck
Wasn't the N&W 2-6-6-4 firebox behind the drivers?
Woulda thought a couple others, too.
Pictures show the Seaboard Air Line 2-6-6-4 locomotives as well as the Pittsburgh & West Virginia 2-6-6-4 locomotives had the firebox completely behind the drivers like the Norfolk & Western A.
What I am saying - not all of C&O's use of the engines was on their 'mountainous' sub divisions. Did find two DOT investigations that mentioned 1600's. In the first report, a 1600 was pulling a 102 car train between Columbus and Walbridge. In the second report a train with a 1600 had passed the accident area shortly before the train involved in the accident happened a little distance outside Clifton Forge.
https://dotlibrary.specialcollection.net/Document?db=DOT-RAILROAD&query=(select+3373)
https://dotlibrary.specialcollection.net/Document?db=DOT-RAILROAD&query=(select+3374)
Well, yeah. I figured you guys would come up with some more.
Still, it's interesting that there's this difference.
7j43k Well, yeah. I figured you guys would come up with some more. Still, it's interesting that there's this difference. Ed
No doubt the massive and deep firebox on the 1600s behind the drivers was a major factor in their horsepower development.
It would have been interesting to see how one of these would have performed on Oris’ and Mantis‘ C&O “cousin” Nickel Plate Road in High Speed Service, but I suppose every siding between Chicago and Buffalo would have had to been extended to handle at least 1.5 times the train lengths handled by the Berkshires and every turntable enlarged.
kgbw49 No doubt the massive and deep firebox on the 1600s behind the drivers was a major factor in their horsepower development.
Mayybeeee....
One could speculate that the square footage of lost surface area in the firebox caused by raising the bottom (from the 2-6-6-6's height to that of a Challenger) could have been made up for by lengthening the grates and/or the combustion chamber.
I brought the point up originally because of hearing how adding a trailing truck would allow the firebox bottom to drop down, enlarging the firebox. And yet most of articulateds WITH trailing trucks did not have the firebox bottom lowered.
It struck me that most articulateds with trailing trucks did not take advantage of the common claim that it allowed a larger firebox. The Allegheny and the 2-6-6-4's did.
7j43kOne could speculate that the square footage of lost surface area in the firebox caused by raising the bottom (from the 2-6-6-6's height to that of a Challenger) could have been made up for by lengthening the grates and/or the combustion chamber. I brought the point up originally because of hearing how adding a trailing truck would allow the firebox bottom to drop down, enlarging the firebox. And yet most of articulateds WITH trailing trucks did not have the firebox bottom lowered.
Ed, it doesn't work that way. There's some gain from extending the grate (if you can fire it effectively, something the Big Boys 'cheated' a bit to do) but it's not nearly the same as the advantage from greater rise from mudring to crown -- the same thing that makes narrow-firebox engines like the French 240P steam so remarkably well.
Challengers are a kludge of sorts at the back end, not realizing as much gain from the portion of the firebox that may be over the trailing truck (it is if anything a bit higher than the part over the drivers as the grate has to slope forward to feed coal properly as it burns down). Lima made a great deal of the advantage from deep fireboxes 'behind' the drivers, just as Beyer-Peacock made much of the deep fireboxes possible in a Garratt. These are important considerations.
Now, if you want a four-wheel lead truck (for stability or other reasons associated with higher road speed) with two Mallet-style engines, the overall length with a full deep firebox would be considerably longer than the Challenger type; the practical length of the convection section at practical aspect ratio will still be little more than 20', and the lion's share of the substantial mass of the larger firebox and circulation will have to be carried on the trailing truck - hence the three axles in late Lima designs. About the longest practical arrangement you can have is the 'stretched 4-10-4' that was the Q2; beyond that, you're better off with a good 2-wheel truck as on the AMC Berks (and, for different prioritized reason, the L&N Big Emmas).
The Challenger (and Big Boy) is more like an extended version of the 2-8-8-2 idea: the boiler rides entirely above the drivers, and the trucks on either end are optimized for relatively short length given desired overall axle loading numbers.
One reason the Cunningham circulator is so effective is that it increases effective circulation pattern in the water legs in these large, deep fireboxes with multiple syphons or central circulators. Much of the advantage of the deep box is in better natural circulation and steam-separation without DNB in the radiant-uptake areas, and better defined circulation improves this still further.
Best of all, of course, is a LaMont-style setup with defined fast circulation through waterwall tube construction (the feedwater going through about 6x the mass flow of delivered steam). The 'catch'is how the tubes are arranged in a locomotive-style firebox arrangement...
Are/where there any steam locomotives with trailing trucks, excepting articulateds, that had the firebox partially over the drivers?
7j43k Are/where there any steam locomotives with trailing trucks, excepting articulateds, that had the firebox partially over the drivers? Ed
Um, the Union Pacific 4-12-2 "Nines"?
That locomotive is Plate 62 in Alfred Bruce "The Steam Locomotive in America."
Plate 126 shows a 1923 ALCo 2-8-2 of unspecified railroad with the fire box extending over the last driver.
Bruce's book has a survey of wheel arrangements, rigid-frame and articulated, that goes into design trades in firebox placement. On p 328 describing the 4-6-6-4 Challenger type, "the grates were generally blocked off at the rear of the throat to provide clearance for the rear drivers as developed on the three-cylinder (4-12-2)-type engines."
So 2 and 4-wheel trailing trucks were indeed used in a complicated compromise in firebox height and grate area when a large firebox had to extend forward from the trailing truck to partway over the drivers.
By the way, Alfred Bruce "The Steam Locomotive in America" is a fun, easy-to-read book with detailed text along with a supporting pictoral section on 20th century steam. I recommend it.
Overmod had also suggested Angus Sinclair, "Development of the Locomotive Engine." That book concentrates on early, 19th century steam. Now I have been told that a lot of the problems that the advanced 20th century designs tried to solve with varying degrees of success were known to 19th century locomotive design engineers. Sinclair's book isn't as "accessible" to me in its writing. Maybe I need to just read it on its own terms to figure out what it is trying to say? Are there parts I should read first?
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
Paul, just speaking from experience the somewhat archaic writing styles of the 19th Century (and 18th Century for that matter) does take a bit of getting used to, but they're not bad once you get used to them. The thing is to slow down a bit so various bits of the writing don't act like visual speed-bumps.
And of course, some people could write better than others, that's always been the case. Despite their abilities and education not everone was a Charles Dickens, or a Mark Twain for that matter.
I've got a reprint of an 1889 book called "The American Railway," an anthology of various articles by various authors, and some are certainly better than others.
LIMA'S WOODARD ANSWERS THE QUESTION
Purely by coincidence I was paging through some old Railway Age magazines and found an article by W.E. Woodard, Vice President, Lima Locomotive Works, the man who designed the famous A-1 2-8-4 and is credited with introducing "super-power" locomotives. In the article he answers the question originally posed in the Forum, that is, was the Allegheny wasted by often being used on slow coal trains rather than in service where its high horsepower could be better applied.
The article is titled MODERN LOCOMOTIVES FOR SECONDARY SEVICE, and appeared in the April 20, 1929 issue complete with several diagrams, charts and tables (Abstracted from a paper presented to a professional group). In the article Woodard advocated using modern super-power specifically designed for branch line or secondary line service rather than relying on old, outdated power dispalced from main line service.
The locomotive Woodard proposed was a light Hudson 4-6-4 with 69" drivers, 250 lbs. steam pressure and a tractive force of 50,700 lbs. with booster. The engine was proposed for dual service, mainly freight but also passenger service. A drawing of the locomotive was included and it appeared something like the A-1 with a similar articulated trailing truck but given the small drivers and large boiler there was a pronounced space between the leading truck and drivers. It even had tandem main rods and limited cut-off. Woodard said, "It is perfectly possible to replace practically all of these old and obsolete types with one single design of locomotive".
Woodard realized that many would scoff at the idea of buying a super-power locomotive for lowly service so wrote the following about the issue of applying super-power elements to low grade service:
"These are the essential elements in locomotive design which produce power output at speed with economical performance. Objection may be raised that such provisions are not warrented in the class of service to which secondary locomotives are generally used and that full advantage cannot be taken of these power producing elements. The answer is that they are equally as useful in promoting economical operation as in producing high power output. And, moreover, we believe it will be found that such characteristics are highly desirable in a general service locomotive."
Unfortunately, the article appeared only months before the Great Depession reduced the need for locomotives and made it difficult for most railroads to finance modern locomotives. Remember that the Illinois Central did convert an A-1 2-8-4 into a freight Hudson in 1937 -- not exactly what Woodard had in mind but interesting nonetheless.
Paul Milenkovic Plate 126 shows a 1923 ALCo 2-8-2 of unspecified railroad with the fire box extending over the last driver.
It's noted under the photo in Bruce's book that the locomotive was built for stock (without a buyer in mind). It looks a lot like a typical larger logging locomotive. Here's another:
I'll note that, in both photos, the firebox is not ABOVE the drivers, but BETWEEN the drivers.
Also of note is that, in both photos, the trailing truck axle and the lead truck axle are both about the same distance from the drivers. The trailing truck wheels are actually BEHIND the firebox. For weight bearing purposes, this was not necessary. But I suspect it came in handy when backing up, which these locomotives did quite a bit.
I do not consider these logging-type locomotives as germane to the discussion.
The 4-12-2, though, certainly is. I thought perhaps the 4-10-2's might also be in the club, but only one is: Baldwin 60000. Here's an interesting photo illustrating that:
and here's one that's perhaps a bit more flattering:
nhrand LIMA'S WOODARD ANSWERS THE QUESTION Purely by coincidence I was paging through some old Railway Age magazines and found an article by W.E. Woodard, Vice President, Lima Locomotive Works, the man who designed the famous A-1 2-8-4 and is credited with introducing "super-power" locomotives. In the article he answers the question originally posed in the Forum, that is, was the Allegheny wasted by often being used on slow coal trains rather than in service where its high horsepower could be better applied. The article is titled MODERN LOCOMOTIVES FOR SECONDARY SEVICE, and appeared in the April 20, 1929 issue complete with several diagrams, charts and tables (Abstracted from a paper presented to a professional group). In the article Woodard advocated using modern super-power specifically designed for branch line or secondary line service rather than relying on old, outdated power dispalced from main line service. The locomotive Woodard proposed was a light Hudson 4-6-4 with 69" drivers, 250 lbs. steam pressure and a tractive force of 50,700 lbs. with booster. The engine was proposed for dual service, mainly freight but also passenger service. A drawing of the locomotive was included and it appeared something like the A-1 with a similar articulated trailing truck but given the small drivers and large boiler there was a pronounced space between the leading truck and drivers. It even had tandem main rods and limited cut-off. Woodard said, "It is perfectly possible to replace practically all of these old and obsolete types with one single design of locomotive". Woodard realized that many would scoff at the idea of buying a super-power locomotive for lowly service so wrote the following about the issue of applying super-power elements to low grade service: "These are the essential elements in locomotive design which produce power output at speed with economical performance. Objection may be raised that such provisions are not warrented in the class of service to which secondary locomotives are generally used and that full advantage cannot be taken of these power producing elements. The answer is that they are equally as useful in promoting economical operation as in producing high power output. And, moreover, we believe it will be found that such characteristics are highly desirable in a general service locomotive." Unfortunately, the article appeared only months before the Great Depession reduced the need for locomotives and made it difficult for most railroads to finance modern locomotives. Remember that the Illinois Central did convert an A-1 2-8-4 into a freight Hudson in 1937 -- not exactly what Woodard had in mind but interesting nontheless.
Unfortunately, the article appeared only months before the Great Depession reduced the need for locomotives and made it difficult for most railroads to finance modern locomotives. Remember that the Illinois Central did convert an A-1 2-8-4 into a freight Hudson in 1937 -- not exactly what Woodard had in mind but interesting nontheless.
Interestingly, both Illinois Central and Canadian Pacific took Woodward’s advice - sort of.
IC converted older Pacifics to freight service with lower drivers.
CP built new G5 Pacifics specifically for branch line service in the 1940s.
CP also built new G3 Pacifics for dual purpose usage in the 1940s, albeit primarily for main line usage, but intended to be both freight and passenger haulers nonetheless.
nhrandIn the article [Woodard] answers the question originally posed in the Forum, that is, was the Allegheny wasted by often being used on slow coal trains rather than in service where its high horsepower could be better applied.
Actually, this is something he DOESN'T address ... at least in the sense you mean.
He is advocating precisely that a design for slow-speed be optimized for efficient (hence, economical) operation in the specific services for which the locomotives are provided. We would not, for example, expect to see his '30s design for high-speed four-coupled locomotives adapted for 'secondary service' even if that included passenger work that might take advantage of high speed at some point. Note that this is less than a year later than his discussion of the 'Central Machinery Support' 2-12-6, which is perhaps interesting to consider as his 1928 thinking on a "12-drivered" locomotive; the effect of Eksergian's paper on effective locomotive balancing published that same year had not had much time to 'gain traction' in providing effective solutions for good balancing of relatively low-drivered locomotives (cf. the package that converted the T&P 600s from drag-freight Super-Power to relatively capable passenger-capable power in the 1930s as recounted in at least one Trains article).
That does not make the article worth any less from the standpoint of assessing what 'good contemporary choices' for motive-power design details in a particular service ought to be. I would ask only that we remember a considerable number of 'enabling technologies' in reciprocating-locomotive design were developed subsequently, sometimes with a terrible learning curve (ACL R-1s, anyone?) before their often frankly common-sense implementation was 'mainstreamed'.
... Woodard advocated using modern Super-Power specifically designed for branch line or secondary line service rather than relying on old, outdated power displaced from main line service.
Now, I am tempted to be a bit sarcastic and note you clearly have a Lima designer doing this discussion. You, I, and the person behind the tree would know, even by 1929, that the articulated trailing truck alone would make this a holy horror if, you know, the engine were expected to perform something like trailing-point backing moves or substantial reverse running on typical 'secondary' trackage of that era. We won't go into the fun of keeping complicated steam auxiliaries like FWH pumps running 'in the boonies' to keep the fuel bill minimized -- some railroads, C&O among them, recognized that even first-line large power might be "cheaper" to run without the complications at some rate of return far better than that of secondary service. Where he thought railroads would get the capital to buy these shiny new engines instead of working additional miles out of that paid-for cheap earlier power is unclear to me, even before the New Era came crashing down; what actually happened on some (perhaps many!) railroads was that the 'shiny new technology' came to be applied in rebuilds (to reset the tax clock on depreciation, etc., more than real tangible benefits in operation) instead of at full price on new locomotives -- Frisco 1351 and 1352 are poster children for this practice -- and one might suspect that this would be as true in the late '20s as in the late '40s.
One likely problem that could easily be foreseen is that railroads wouldn't treat the 'replacement' single design relative to the capabilities of the various older locomotives it would replace -- one very important 'likelihood' being that the new engine would become treated just as C&O did the Alleghenies (or PRR, the T1s): flogged to increase perceived 'return on equity' by taking the full modern output as the number for calculating effective 'train ratings' for service.
To me, this suggests something that the English engineer Tuplin observed NYC doing with one of the Niagaras: by using a version of sliding-pressure firing, the engine could be made to do the work of an earlier-class 2-8-0 on the 2-8-0's consumption of fuel and water. Nifty ... until you consider All That Capital (and greater length, complexity, etc.) tied up doing that little job, and then starting to wonder if that was all being wasted when more cars could evidently be tied on and handled...
Woodard realized that many would scoff at the idea of buying a super-power locomotive for lowly service so wrote the following about the issue of applying super-power elements to low grade service: "These are the essential elements in locomotive design which produce power output at speed with economical performance. Objection may be raised that such provisions are not warranted in the class of service to which secondary locomotives are generally used and that full advantage cannot be taken of these power producing elements. The answer is that they are equally as useful in promoting economical operation as in producing high power output. And, moreover, we believe it will be found that such characteristics are highly desirable in a general service locomotive."
And here we have an unintentional echo of all those unsuccessful things from the 1920s that were aimed at 'increasing thermodynamic efficiency' ... but at a cost, or maintenance headache, or increased likelihood of road failures, that made any such Big Savings for years and years of fleet operation disappear with a sad sizzle as soon as the problems started to occur. Some of the 'best' of L.D.Porta's thinking has the same characteristics when you look carefully at how they would be long-term implemented.
The answer is almost always that robust, simple, and a bit wasteful is preferential to high-dollar saving of a few percent on what is already a gloriously inefficient thermodynamic 'cycle' for most secondary steam service. When we do see a good-performing 'general-purpose' locomotive for secondary service adopted ... it was a well-designed diesel-electric from Dilworth et al. (mind you, after an almost ridiculous false start designing the wrong kind of secondary-service power, the BLs) and not steam with its limitations at all.
I am surprised that no one has mentioned William L. Withun's analysis in his new 'American Steam Locomotives'. Chapter 18 is about the Big Boy and the Allegheny.
For each he describes the development process and then their performance in the roles they were designed for, after spending much time earlier in the book on the issues of Gross Ton Miles per Hour and the economics of producing those GTMPH. The Super Power salesmen were selling some combination of increased speed and increased tonnage ratings, and it was not a hard sale if the competitor was a 20 year old 2-8-2.
The C&O went wrong from the start. The AMC was its own little fiefdom. The only credible explanation for what happened is that Chairman Daniel Ellis was green with envy at competitor N&W's class A 2-6-6-4 which developed more than 6,000 drawbar horsepower. Ellis decided they had to beat the N&W in terms of HP and that a 2-6-6-6 was the way to do it. The design started ot heavy, Lima found another 30,000 pounds in the design that the C&O overlooked and it got heavier as further changes were made, resulting in very high axle loadings.
The AMC did NOT talk to the operating guys about what they needed. The result was that the Alleghney had no impact on the opertion of the territory it was designed for. Train weight and length were unchanged due to other operating restrictions. Worse yet, the C&O engines had a lower tonnage rating than did the Big Boys (of about 6,000 hp) on equal grades, both at 10-15 MPH. Big Boys were rated for 4,400 tons on 1.14% grades while the Alleghneys were rated for 2,950 on their 1.14% grade. The C&O grade was not compenstated, which knocked the Alleghenys down by about 800 tons. Adding back 800 tons, we get an adjusted rating of 3,750 tons.
Why the disparity when the Alleghney has 7,000 hp and the Big Boy about 6,000 hp? Because the BB has two more powered axles and higher tractive effort all the way up to 30 MPH.
Withun concludes that the Alleghney was '... simply the wrong design for the C&O.' He goes on to suggest that a 16 driver engine with slightly bigger drivers than the (simple) H-7 but smaller than the Big Boy would have been a more economical choice for the C&O.
Mac
Don't be too hard on the Advisory Mechanical Committee. After all, they did come up with excellent 2-8-4 and 2-10-4 designs.
PNWRMNMEllis decided they had to beat the N&W in terms of HP and that a 2-6-6-6 was the way to do it.
Don't think C&O mentioned the 1943 test results in Rwy Age or Rwy Mech Engr (or any other publ?). They knowingly ordered a stupid engine, planning to set the horsepower record -- then didn't publicize the record when they supposedly got it?
C&O ordered ten 2-6-6-6s, and supposedly set the HP record. So why order more of them? The HP record's in the bag; after 1943 they were free to order big 2-8-8-2s, and keep the fans happy. They could run the 2-6-6-6s Russell to Toledo and get a 16-driver railfan-approved engine to haul coal to Alleghany.
timz PNWRMNM Ellis decided they had to beat the N&W in terms of HP and that a 2-6-6-6 was the way to do it. That's what railfans like to think. Aside from the general implausibility--
PNWRMNM Ellis decided they had to beat the N&W in terms of HP and that a 2-6-6-6 was the way to do it.
That's what railfans like to think. Aside from the general implausibility--
Timz,
You are not arguing with me but with Withuhn who I am 100% confident knows more about steam engines than you and I put together.
What was truly striking to me was that they were no better at the job than their predecessor 2-8-8-2s were. C&O spent more money to get no better perforance with extreemly high axle loadings which put more stress on the entire track structure which had to have increased track maintenance exense and probably caused a few derailments that otherwise would not have happened.
My personal opinion is that Withuhn is correct. Read the book!
Withuhn knew that a big 2-8-8-2 could pull more tonnage up a given grade than a 2-6-6-6. All us fans know that, and C&O certainly did.
What did Withuhn know about 2-8-8-2s vs 2-6-6-6s that C&O didn't know?
Nothing -- and maybe he knew that. But he figures C&O knowingly chose a stupid engine. Fans always like to think railroads are run by blockheads.
timzC&O ordered ten 2-6-6-6s, and supposedly set the HP record. So why reorder? After 1943 they were free to order big 2-8-8-2s, and keep the fans happy.
Do you actually think that or is that supposed to be sarcasm? Sarcasm is "a sharp, bitter, or cutting expression or remark; a bitter gibe or taunt". Sarcasm may employ ambivalence, although sarcasm is not necessarily ironic.
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