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| Bennington Towards Horseshoe |
Trains heading west out of Gallitzin descend the "west slope" at just a hair under 2%, while trains coming east have an easier 1.5% climb. The west slope is represented by a three and one half level four track helix. Since there is not enough room to model the west slope to Johnstown, the helix returns the mainline to the eastern end of the layout. That end is represented by the bridges and tunnels at Spruce Creek...
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| Juniata River, Spruce Creek |
The balance of the right of way is level, except for Track 4 at Homer, which passes over Tracks 2 and 3 on a short flyover. In the real world this flyover was across the yard from the East Altoona roundhouse and was actually the approach to the "hump" for the westbound classification yard. On the Allegheny Eastern there was no practical way to model the hump yard, but I wanted the appearance of HOMER on the layout...
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| East Altoona Towards HOMER |
Pictures of other areas of the layout ready for ballast strip and track...
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| Horseshoe |
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| Bennington |
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| Horseshoe Towards Slope |
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| UN Towards Tunnels |
Sometimes you trip over things you would never find through more normal channels. They're not necessarily things you want to know but you learn them in spite of yourself. Case in point, the Pennsylvania Railroad and applied physics. Please excuse my rather verbose and self indulgent "treatise" on the subject.
On the revised version of the track plan dated May 27th 2013 I created a new set of "mile markers" that includes the entire layout, not just the east slope. I couldn't think of another name for them, but they are not spaced a scale mile apart. Instead I put one every every 12". I use them as reference for all kinds of things, mainline and block length, speed estimates, signal locations and several other uses. All of them are numbered on the plan although in the drawing below the numerals are not visible. You can, however, make out the circles on the tracks that indicate a "mile marker". . I did not bother with mile markers in the helix. The track length in the spiral is approximately 34.5 feet, just over a scale mile. I may add some kind of markings to the helix itself, for reference, but not to the plan.
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| Allegheny Eastern May 27th, 2013 |
You can see that the visible mainline splits, merges, crosses over itself and twists in all kinds of confusion. This isn't an attempt to get too much railroad in a small space (although it sure looks it). I tried to replicate in miniature some of the things that caught my attention about this stretch of the PRR. This resulted in complications I had never even imagined. It also made me realize some of the confusion a multi-track mainline can cause for a real railroad. Hopefully I can illustrate some of these challenges as faced by the Allegheny Eastern
MP001 is at the beginning of the Spruce Creek area, 0" elevation as far as the layout is concerned. Tracks 1 and 2 (right) are already split from Tracks 3 and 4 (left) as they emerge from the tunnel portals. MP001 is the same on all tracks. All four tracks share the same mile markers as they approach Forge Curve at the lower right corner. Round about MP004 that starts to change. Tracks 3 and 4 start to "pass" the other two, chiefly because of the differing radii of the curves...
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| Mile Markers at Spruce Creek |
Passing through Forge the inner tracks gain about 6" and stay that way until the flyover at HOMER. This is where Track 4 passes over Tracks 2 and 3. Meanwhile Track 1 continues uninterrupted on its way into East Altoona. This small space is where the confusion really begins. You can see there are THREE MP010's! Tracks 1, 2 and 3 line up, but Track 4 pulls ahead of Track 3 by another few inches. There is also some issue with track identification. Technically, the track arrangement (starting from the South) is now 1, 4, 2, 3. Tracks 1 and 4 come together as they enter East Altoona, albeit at different mile posts. Tracks 2 and 3 start to bypass Juniata on their way to Altoona...
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| Mile Markers at HOMER |
By the time they pass East Altoona, Tracks 2 and 3 are beginning to fall behind as the four tracks curve toward Juniata. By the time Tracks 1 and 4 reach the yard Track 1 has gained nearly a foot.on 2 and 3....
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| Mile Markers at East Altoona |
This situation gets more confused as the mainline reaches Altoona station. The passenger mains (Tracks 2 and 3) are well over a foot behind Track 4 and almost three feet to the rear of Track 1. Rather than keep going with three different sets of mile markers, at MP033 I stopped with the separate markers for tracks 2 and 3 By MP035 all four tracks have a consistent mile marker. I also returned to the "normal" track arrangement of 1, 2, 3 and 4. The crossovers allow trains to move to the "proper" track for their ascent of The Hill. I did leave the Track 1 markers as a reference. This is the longest track and is used to measure the overall length of the mainline...
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| Mile Markers at Altoona |
This goofy offset continues through the entire climb up the east slope until the mainline enters Bennington. At this point the tracks split again. 1 and 2 (eastbound) stay together and pass through New Portage tunnel. Tracks 3 and 4 (westbound) split from each other and run parallel into the twin tunnels, Gallitzin and Allegheny. As the westbound tracks sweep around Gallitzin they gain "mileage" on the eastbound. By the time the main merges west of Gallitzin the westbound main has traveled five feet more than the other...
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| Mile Markers at Gallitzin |
So what has this to do with anything? Believe it or not, it's not just a "difficulty" with the trackplan of my model railroad. It happens on real multi-track railroads. Consider the very railroad the All East represents, the Pennsylvania. Take a look at the track chart at SLOPE from 1945...
Now aside from the juxtaposition of track numbers (other railroads number in reverse starting from north) there are curious notations at the top. See the numbers between the mileposts. They are there to indicate the distance between mile markers. The key word here is "mile". In school I was taught that a "mile" is 5,280 feet. So it has always been, at least since they standardized measurements. It is not 5,266, nor is it 5,313 or any of the other numbers on this track chart. In fact the number 5,280 turns up but three times between MP214 and MP250. I haven't looked at charts for any other railroads, so I don't know if this was a common practice. Because of the eccentricity of the Pennsy, I wouldn't be surprised if the management decided to interpret the term "mile" to suit their own purposes. Near as I can tell it can be anywhere between 4,646 to 5,311 feet.
I have no idea what lies behind this. The most obvious to me is that no matter how you slice it all track lengths of a four track mainline cannot be equal. Maybe the PRR figured it didn't really matter and picked an average distance. It could also be a result of one hundred odd years of changes, improvements, repairs and God knows what other influences. I'm sure there was a definite reason to shrink or stretch a mile. It does make one wonder though. Regardless of Einstein or Hawking, the Pennsylvania Railroad apparently had no problems bending the time-space continuum to their own needs. In model railroading we have gotten used to fast time clocks and "smiles" to make our mainlines longer and allow us timetable operation. It's been like that for decades, I just didn't know there was a prototype for it.
The area being modeled on the All East extends from MP214 at Spruce Creek to MP250 at Gallitzin. According to the mile posts on the charts that distance is about 36 miles. According to the numbers between the mileposts, the actual distance is about 35.75 miles. Mind you there are some gaps in the notations. No distance is noted between MP036 and MP037. This is where the Middle Division meets the Pittsburgh Division. I assumed this distance was an actual standardized mile. The other gap falls between MP239 and MP240. All the chart shows are the numbers 67. I guessed at 5,267. To me, however, the missing 0.25 miles doesn't compare with the disparity of the indicated distance in feet. Of the 36 numbers noted, about 30 of them are not equal to any of the others and almost none of them measures an actual mile. The miracle is that they managed to make all of these odd distances add up to 36 miles, give or take. I checked several charts I have for the Pittsburgh Division from 1941, 1945 and 1958 as well as Sam Beliner's 1972 charts at his PRR site. Same numbers no matter what decade you reference after 1941.
I can only conclude that there really is a prototype for every situation, no matter what dimension, time or position in space you are viewing it from.
Regards,
Frank Musick
Chief Cook and Bottle Washer
I can only conclude that there really is a prototype for every situation, no matter what dimension, time or position in space you are viewing it from.
Regards,
Frank Musick
Chief Cook and Bottle Washer
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| Allegheny Eastern Railroad |
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