Following the construction and commissioning of the new towns of Carson and Curlew with their additional industries, a new operating scheme was developed to include service to these new towns. It was a simple extension of the one used to date, whereby trains from all four compass points would exchange cars in Grand Forks as well as service their assigned industries. The local industries at Grand Forks were switched also as part of the classification switcher duties at an appropriate point in time. This proved quite successful, and it was used during VanRail 2017 for two sessions.
With the significant increase in industries wanting cars, the classification role at Grand Forks was expected to become a full time position, leaving the local industries to be switched by a different job.
The Saturday gang bravely agreed to try out these ideas on one Friday evening that will be well remembered for all the wrong reasons. Let’s just say that my ideas didn’t quite work out as planned. If you are interested in the gory details of my analysis, it continues below the following pictures that were taken before everything went wrong.
So, here goes… With more places to spot cars, more cars were needed on the layout. A quick simulation with 60 extra cars proved that the layout could absorb that many, as it settled into a nice stable pattern after about 15 days. There were only 28 extra actual cars available for the layout, so these were added and it settled into a nice stable pattern after about seven days. The operating session in question was based on the eighth day after stability was reached. Remember, this was all inside of my computer simulation and had yet to tested in practice.
The way that the Grand Forks yard was used required that there be more places to group and hold cars than the number of physical tracks. This meant that a dynamic location assignment scheme was needed, whereby the groups of cars for one specific destination might have to be moved to different physical tracks over time as the number of cars ebbs and flows. The current locations of these groups were maintained by using a magnetic track diagram with moveable labels for the groups. This approach has worked well for three years when there have been fewer cars, and the crews could keep up with the traffic flow.
With the addition of 28 (and even the test 60) extra cars, it turns out that there is in fact still sufficient total room in the Grand Forks yard, but the increased necessity to move the various blocks of cars around and the sheer number of cars getting in the way of these moves proved to be too much for the local crew on their first attempt to switch the yard, resulting in significant frustration and lack of enjoyment, to put it mildly…
One concern with the original operating scheme was that there was not sufficient work to keep a dedicated classification switcher busy full time. With the addition of more downstream industries, it was felt that the increase in cars needed on the layout would generate more interchanges at Grand Forks, thereby enhancing the classification job into a full time position. The resulting increased traffic through Grand Forks with the additional cars being switched for the new industries has proven this true. Unfortunately, however, the limited space at Grand Forks has made the physical task to classify such a congested yard not manageable in practice.
One very positive outcome of these tests is a confirmation of the program’s capability to handle the classification style of yard switching, as opposed to other programs that have no such ability. The program was able to process more cars through the yard using a prototypical switching style, whereby blocks of arriving cars are immediately classified into their respective outgoing blocks, thereby avoiding “cherry picking” by subsequent departing trains. It was able to handle complex car moves up to the full capacity of the yard without a problem, even to the point that the resulting physical moves became close to impossible to carry out.
What all this implies is that a different approach to running the Grand Forks yard is needed, especially as additional future towns with even more industries will be added in the future. The method of processing cars in the yard is the correct one and very prototypical, except that the number of cars being handled is more than can be comfortably managed by a person, given the total space available to work in. Technically, it all fits, but it ends up being much too complicated in practice. The number of cars needing to be interchanged could be reduced by fiddling with the shipment information, but the fact remains that there will be an increasing need for significantly more cars to be switched at the current and future towns, so this is not a viable solution.
The main conclusion seems to be that the space at Grand Forks is far too limited to try to operate it as a classification yard in the full sense of the word. Some limited interchange is desirable and should be possible, but this would be accomplished by the various road trains that visit the town, and not by a dedicated classification switcher.
Time for some serious thinking and reflection. To be continued…