The problem here is that it’s dancing around the important issue here: whether east or west of Clifton Forge, C&O apparently chose to routinely load down the Alleghenies to the point they regularly ran 20mph or more below their best-horsepower speed. Whether or not this represented ‘lowest net cost’ vs. running lighter trains more quickly is immaterial if considering better, or more economical, locomotives optimized to run at the speeds C&O wanted.
We have still not addressed whether C&O ran a significant mileage per month of non-wartime fast freight with these locomotives, and what both the average and peak speeds of that service were (or had to be). That determines the ‘other half’ of the question that was asked: how fast would the alternative ‘have’ to run to be an effective alternative to the Alleghenies? This can be answered, but better by someone like Dave Stephenson, who knows the actual details, than by me.
The locomotives did the job the C&O wanted done at what the C&O considered a reasonable cost. If they had not done the job or had cost more than what the C&O considered reasonable they would have been replaced post haste.
The utility and economy of diesel-electric locomotives replaced all steam in short order after it became available consistant with manufacturing capacity.
Have any of you heard the old adage…“Don’t worry about the mule, just load the wagon”? There is the answer to many of your questions!
I don’t personally know of any sound recordings of C&O coal trains on a grade. If they do exist, I seriously doubt that you would be hearing a coal train running anywhere close to 15 mph on the ruling grade! Remember that the real world is very different than what you railfans percieve it to be.
There’s a saying here also. As long as the load gets to the final safe the customer doesn’t care if the truck is a Pete Freightliner KW or Volvo. Only the driver and the name on the door matters. The only person that complains that complains about what brand of truck it is are the driver. In railroading the beancounters don’t care what engine pulls the train as long as it gets it there the only ones that bitch are the RAILFANS and the crews when it comes to the GE EMD wars.
The original question was whether the C&O should have bought more 2-8-8-2’s rather than 2-6-6-6’s that allegedly produced more horsepower than the C&O could use on its coal trains. I suggested in an earlier post that I think the C&O made a reasonably good decision in buying the Allegheney type and will elaborate a bit. I assume the C&O wanted a dual service locomotive although it seems coal train use predominated. The criticism of using the H-8 Class mainly in coal service is that its peak horsepower developed at higher speeds and therefore the engines should have been used at speeds at which the horsepower output was at a peak.
I 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. The Class Y6b produced more drawbar horsepower than the Class A until about 32 miles per hour at which point the horsepower of the 2-8-8-2 fell substantially. The peak drawbar horsepower of the Y6b was about 5,500 at about 25 mph while the 2-6-6-4 peaked at about 5,200 at about 35 mph. However, due to the high capacity of the boiler, the Class A maintained that same high drawbar horsepower at 60 mph or more. By the time the Y6b had reached a top speed of about 40 mph, drawbar horsepower had dropped to nearly 4,000. (We seldom talk about the drawbar horsepower of a diesel but that is another story.)
If the C&O had wanted to restrict the Allegheney type to purely coal trains a 2-8-8-2 would have done the job but flexibility would be lost. The Allegheney could easily handle coal, merchandise or passenger trains. The power was there when needed. Whether it was need often enough to justify the cost of such a large engine is hard to say. Was it being wasted when it was used on coal trains&n
Apparently the test trains did anywhere close to 15 mph – they ran Hinton to Alleghany in about two hours.
The Allegheny - Lima’s Finest quotes a report on the test with two H-8s – says they got stopped by a red signal on 0.57% just west of MP 316. After the stop they reached 18 mph in 2-1/2 miles.
I know population and traffic levels north of the border at the time made a high-speed articulated unnecessary, but it would have been something to see what a CN or CP 2-6-6-4, 4-6-6-4 or 2-6-6-6 would have looked like.
Yeah a Challenger on the Prairies between say Winnipeg and Calgary would have been a sight on the Dominion. The CPR had 0-6-6-0’s in the mountains for a bit. Some logging roads had articulates but that’s a different cookie.
The key word being “test”. Show me what they did hauling actual everyday tonnage.
Before you go reading too much into this and coming to wild fantastic conclusions, remember that tonnage can be adjusted so that the train can make a certain speed upgrade. The less tonnage (read less profit), obviously the greater speed.
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
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.
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.
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
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
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.
You first have to realize that just because you see “X” amount of locomotives in a consist, that doesn’t mean all of them are on line and working. There are rules that limit how many axles in power can be on line at one time. Even more limiting than that, there are also rules as to how many axles of dynamic braking can be used and it is less than in power.
One reason that you see large consists of locomotives is to balance power needed at certain locations. For example, you run ten trains north, but, you only run five trains south. You have more power up north than you need, so, you send the extra power back dead or isolated to the point where you need it.
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.