Thursday, April 4, 2019

Patterns of SP train operation

My title today is perhaps over-general, as I am only going to discuss Southern Pacific operation in the 1950s. And not only that, but I am only going to talk about SP’s Coast Division. Within those restrictions, though, the title is accurate.
     Veteran SP employees, mostly from West-Coast operating backgrounds, and particularly Malcolm “Mac” Gaddis, who worked at San Luis Obispo in the early 1950s, have told me that the patterns I describe below were pretty universal on SP in the West, but I don’t know whether they would have extended elsewhere on SP, or on subsidiaries such as Texas & New Orleans.
     (I have reproduced the text of parts of my interviews with Mac in posts to this blog in prior years. You can readily find them by using “Gaddis” as a search term in the search box on the upper right-hand side of the present post.)
     I am presenting this summary for a simple reason. I have found through repeated instances of descriptions in oral talks about SP operations, that many do not grasp the patterns I am trying to convey. So I decided to take a shot at putting the description(s) into written form, in this post.
     That said, let me begin with a 1906 SP map of Coast Division. I use it here for illustration even though track details will not match the 1950s, because it’s an admirably clear map (you can click to enlarge it if you wish).

On the map, I have emphasized in red the two intermediate “division points,” Watsonville Junction and San Luis Obispo, as well as the southern end of the division, Santa Barbara, with the discussion to center on San Luis, the operational midpoint of the Coast Route (beyond Santa Barbara, the trackage was part of Los Angeles Division). Crews changed at each of these points.
     It was emphasized to me in my interviews with Mac Gaddis, that SP freight operations on the Coast were centered on scheduled freight trains. That meant that additional sections of through trains, and extra through trains between division points, were unusual, with the schedule set up so that freight traffic could be moved with those scheduled trains.
     The point about these scheduled trains is that they were through trains, that is, they ran between division points and ordinarily did no switching en route. The schematic below shows this kind of operation, for trains between the points of San Luis Obispo, Watsonville Junction and Santa Barbara.

To repeat what is important here, all of these were timetable trains.
     So if these through trains did no en-route switching, how were local industries served? They were switched by “turns,” trains running from a division point, to a location about halfway to the next division point, and returning, thus the name "turn.” They switched all the local industries along their route (except for certain cases described in a moment). This is shown schematically below, along with the identity of the two points at which these trains turned in this area, King City and Surf.

Thus there was a “King City Turn” out of both Watsonville Junction and San Luis Obispo, and a “Surf Turn” out of both San Luis Obispo and Santa Barbara.
     The key thing to appreciate about this system of operation is that the turns brought everything back to the division point to be organized and blocked for appropriate through trains. So the King City Turn might pick up a car at Paso Robles, north of San Luis, that was destined to, say, Seattle. But it would be brought back south to San Luis Obispo to be put into a northbound (railroad westward) train to move it toward Seattle.
     When a turn did not have too much switching to do, it could go out and return in a day. But if there was a lot of work, the crew and locomotive would lay over at the turning point overnight, and return the next day. These turns were not scheduled trains and were not in the timetable. They were extra trains.
     Of course, the idea of a turn to handle all local switching may readily run afoul of heavy traffic for individual locations, such as interchange, or seasonal traffic at packing houses. For those situations, a local train was operated in addition to the turns. In effect, such a local supplemented the turn, and took care of excess traffic beyond what the turn could handle conveniently. I can mention two, the Guadalupe Local out of San Luis Obispo, handling all the local perishable traffic as well as interchange with the Santa Maria Valley Railroad, and the Goleta Local out of Santa Barbara, handling all the packing houses at Goleta.

The locals, though having names and regular operation, were not scheduled and were operated as extras.
     Finally, there were times, such as during harvest season, when traffic locally might exceed even the capability of a local freight. For example, at Salinas there were dozens of packing houses, and in season, entire trains of empty reefers needed to be moved there for loading, and entire trains of loads would need to be brought back to Watsonville Junction. Trains of this kind were called “haulers” by SP, and they were almost always seasonal. They too were extra trains and not in the timetable.

     Thus operation on a layout like mine, with a segment of Coast Route mainline track that is situated a little south of San Luis Obispo, might move any of five kinds of freight trains on that segment: scheduled through trains, extra through trains, and three other kinds of extras: turns, locals, and haulers. Note that everything is built around the idea of bringing all switched cars back to a division point for inclusion in a through train to move toward its eventual destination. That is the pattern of switching work on my layout, and it is designed to follow SP prototype practice.
Tony Thompson

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