don7 An attempt at standardization was made by E H Harriamn in 1902 with the Union Pacific and Southern Pacific. Quite and undertaking at the time.
An attempt at standardization was made by E H Harriamn in 1902 with the Union Pacific and Southern Pacific. Quite and undertaking at the time.
I will agree with all of that, and will even add that while the C&O may not have needed the 2-6-6-6, and surely never used it to its potential, it was by far a more versatile answer to the big power quest than the Big Boy
How so? Versatility is determined by use. By that standard, the SP cab-forward was a far more versatile locomotive than either Big Boy or the Allegheny as it was commonly used in operating arenas far removed from its designed use on Donner Pass. The only SP territory where the AC's didn't run were lines east of El Paso and the Siskiyou Line (3% grades ascending grades not advisable with a locomotive with the firebox on the uphill end of the locomotive).
As an aside, both SP's 4-8-2's and 2-10-2's were more versatile than the cab-forwards. The 4-8-2's were used everywhere west of El Paso and the 2-10-2's were pretty much used everywhere.
Actually, your comments reinforce my statement that there could have been more standardization, but there was no incentive to do so.
Not until EMD told the railroads that they could have their FT's in any color they wanted, but that was pretty much it (other than peripheral details like dynamic brakes and Mars lights).
The incentive to standardize should have come from some thoughtful engineering and analysis of the real economic cost/benefit of standardization, not the least of which is a reduction in parts inventory and a commonality of repair procedures (a la Southwest Airlines, which standardized on the Boeing 737).
Just look at the B&O, they liked theirs so much they never owned a 4-8-4. And 4-8-2's were the real work a day locos on the NYC, so is the case here on the ATLANTIC CENTRAL.
Yeah, the NYC had a potload of 4-8-2's. Makes you wonder why other railroads with low grade profiles didn't go for the 4-8-2 in a big way. South African Railways, which definitely doesn't have a low grade profile was a huge user of multiple classes of 4-8-2's. Relative to its size, New Zealand Government Railways was also a large user of 4-8-2's and the last steam locomotive built for NZGR was a 4-8-2.
As a wheel arrangement, the 4-8-2 is my favorite. Sometimes I wonder just what a USRA light copy built with a cast engine bed with cylinders cast integral, roller bearings on all axles, Boxpok drivers on all drive axles, gas producer firebox, poppet valve gear and a Lempor exhaust would be capable of.
Man, we've gotten off-topic.
Andre
Andre,
I will agree with all of that, and will even add that while the C&O may not have needed the 2-6-6-6, and surely never used it to its potential, it was by far a more versatile answer to the big power quest than the Big Boy. Same was true of the N&W class A, way better thought process than the Big Boy.
I also agree that in many, many cases the 4-8-2, in various forms, was the first truely dual purpose, go anywhere, do anything loco.
Sheldon
I will pose this question - why did the N&W choose 70" drivers for their "super power" Northerns but the SP chose 80" drivers - different operating conditions.
The N&W built their own engines and actually put some serious thought into the design and the work to which it would be put. There was no good reason for SP to use 80" drivers. The average speed between LAX and SFO was around 48 MPH on the Daylight and 40 on the Lark, The average speed on N&W's Powhatan Arrow from Newport News to Cincinnati was, IIRC, about 45 MPH. A 70" driver locomotive generally produced its best power at around 45 MPH.. The J was also capable of 100 MPH running, so there was no advantage to the GS-3/4/5 80 " driver. In any case, 100 MPH running is an impossibility on the coast line. Additionally, SP found that its 73" driver 4-8-2's could actually out-accelerate an 80" driver 4-8-4 in commute service, an experience backed up by the experience with 70" driver 4-8-4's from the Cotton Belt. Incidentally, in the mid-50's, SP did use the some of the Cotton Belt engines on the San Joaquin Daylight for a short time.
There was absolutely no need for 80" drivers on the GS-3/4/5 engines from an engineering or performance standpoint. Lima was in the business of selling locomotives, not recommending that railroads could actually use something other than what they wanted to sell. "Super Power" was essentially a marketing strategy targeted at motive power superintendants.
Simple Example - A Big Boy would have been useless on the C&O or B&O. To long a wheel base for good traction in Appalachia.
The Big Boy never should have been built. UP could have gotten better bang for the buck with a 63" driver simple 2-8-8-2, which would have been quite adequate for the Wahsatch grade for which the Big Boys were designed. A copy of the WP M-137 would have sufficed and still would have had plenty of speed capability. You don't need an engine supposedly capable of 80 MPH when the freight cars of the time weren't capable of standing up to those speeds. The M-137's were quite capable of producing 6000+ HP and could essentially equal a Big Boy at track speed as well as having almost identical starting tractiv efforts. The UP got sold a bill of goods by Alco. There may be bragging rights for having the "largest engine", but the performance figures don't really justify the expense and effort. An N&W A could match Big Boy's horsepower and the only question is at what speed would output match (e.g. 2 locomotives producing the same tractive effort at the same speed are putting out equal horsepower at the rail)..
And many of the smaller drivered locos that were of high importantance in the east, would not have served well in the west.
I will grant you that the second hand C&O H-7's and N&W Y-3's were not appropriate for UP's fast mainline, but they alse were obsolete for mainline service on the roads that sold them to the UP, otherwise they wouldn't have been sold. UP had some 2-8-8-0's with similar size drivers that were quite capable of keeping up with things, having been simpled in the 30's, their driver size increased from 57" to 58"and were known to have run at speeds up to 60 MPH.
SP, WP, D&RGW, GN, NP, all used 63" driver articulateds. SP's 4-8-8-2's were actually used in passenger service on some routes (Tehachapi, Donner) and had a speed capability that exceeded 70 MPH. SP's 57" driver 2-8-8-2's which were built in the teens, lasted into the late 40's after being simpled in the 20's and 30's. NP had USRA 2-8-8-2's as did the Rio Grande as well as earlier classes of 57" driver 2-8-8-2's. The GN had 35 oddball 2-6-8-0's with 55" drivers.
By the same token, IMHO, the C&O H-8 2-6-6-6 has got to be the biggest waste of a steam locomotive ever built. It would have been a superb fast freight engine, but C&O wasted its horsepower capabilities on coal trains. A smaller 2-8-8-2 or 2-8-8-4 could have handled C&O coal more efficiently and would have had higher starting traffic effort. They could have used the coal burning SP AC-9 as is (124,300 lbs TE, capable of 6000 HP), but that would have meant putting engineering and economics over ego. Lima built both the AC-9 and the H-8. The AC-9 pre-dated the H-8 by 3 years. If C&O really wanted coal lugging power, the WP M-137 would also have been a good choice
By way of comparison in the diesel years, SP found that the 3,600 HP SD45 was no better than the 3000 HP SD40 on grades and gave them the same tonnage rating (about 1300 tons/unit in Tehachapi, IIRC). Just because it's bigger/more powerful doesn't mean it's better (or even appropriate).
The UP didn't need Big Boys, SP didn't need 80" driver 4-8-4's (nor did anyone else) and C&O didn't need 2-6-6-6's with 40 ton axle loadings that route restricted them. The N&W got it right because they actually thought about what they were doing. The problem with everyone else was massive egos and the idiotic notion that "our conditions are special".
There could have been more standardization, but there really was little incentive. There was considerable standardization of components, trailing trucks, appliances, etc.
As for the "tailoring" thing, there is some very strong evidence in favor of that theory is some aspects.
Diesels over come these problems with the inherent benefits of electric traction - steam locos have fixed "gear ratios" and do not have max torque at zero RPM like electric traction.
ATLANTIC CENTRAL Andre, Thank you, I was just about to go into that explaination. While not a boiler issue, observers should also note that the 2-8-2's shared the same running gear except for piston size and stroke - 63" drivers. The light Pacific had 73" drivers, the heavy Pacific 79" drivers making it appear bigger - it was taller. Sheldon
Thank you, I was just about to go into that explaination.
While not a boiler issue, observers should also note that the 2-8-2's shared the same running gear except for piston size and stroke - 63" drivers.
The light Pacific had 73" drivers, the heavy Pacific 79" drivers making it appear bigger - it was taller.
wjstix If the light USRA mikado and heavy USRA pacific didn't use the same boiler, it was very very close to the same. I'd have check my "Uncle Sam's Locomotives" book, but I think they were the same boiler.
If the light USRA mikado and heavy USRA pacific didn't use the same boiler, it was very very close to the same. I'd have check my "Uncle Sam's Locomotives" book, but I think they were the same boiler.
Same boiler, slightly larger firebox on the Heavy Pacific (70.8 sq. ft vs. 66.7 sq ft.). The grate area on the Heavy Pacific was same as Heavy Mike. The boiler on both heavy 4-6-2 and light 2-8-2 had a minimum diameter of 78" and maximum diameter of 90". USRA Heavy Mike had minimum diameter of 86", maximum 96".
The USRA Light 4-6-2 had the same grate area as the Light 2-8-2, but had a slightly smaller diameter boiler (min. 76", max 86").
The boiler on the heavy 4-6-2 looks larger than the boiler on the light 2-8-2 due to the squat domes on the 4-6-2. Compare the effect of dome height on appearance.
Erie K5 (USRA Heavy 4-6-2 copy): http://www.steamlocomotive.com/pacific/erie2929-mainey.jpg
Chicago & Illinois Midland light 2-8-2 (USRA copy): http://www.steamlocomotive.com/mikado/cim552.jpg
Pedantry. It's not just just for Sheldon Cooper. ;^)
Thank you for the answer.
It is what I was hoping to hear since I am taking another chance buying a BLI.
Strezzy
JimStrez Am I mistaken or is the new BLI Pacific their Mikado in Pacific clothing? Looks like the boiler assembly is all the same and the driver configuration is all that changes. Was the USRA design this similar across the Mikado and Pacific?
Am I mistaken or is the new BLI Pacific their Mikado in Pacific clothing? Looks like the boiler assembly is all the same and the driver configuration is all that changes.
Was the USRA design this similar across the Mikado and Pacific?
Yes and no. The USRA Pacific and Mikado did not share the EXACT same boiler dimensions or specifications - BUT - they are VERY, VERY close. And in 1/87 scale (HO) they are more than close enough for all but the most nit picky modelers.
The entire USRA series of locos shared a great number of common parts, and similar or identical elements.
Another example is that the boilers on the Heavy 4-8-2 and light 2-10-2 are also virtually identical except for sand box and dome placements.
Remember too that the USRA designs became the platform for many "copies" during the two decades that followed WWI. Not every copy was "exactly" the same either.
From a modeling perspective, how close is close enough? I know they will be close enough for me, assuming they actually show up. My only complaint is I would prefer a DC version without sound.
But since I will likely change the tenders anyway, maybe there will be a strong E-bay market for the tenders with the sound in them.