Today we are constantly bombarded with news pertaining to the major locomotive builders' latest technological developments and model offerings. Not so well known yet equally as noteworthy have been the manufacturing programs undertaken by numerous North American railroads, notably such companies as Santa Fe, Illinois Central Gulf and Union Pacific.
Demonstrating the need for switching locomotives in the 1000-1500-h.p. range, UP's motive-power department people studied several options when it became time to replace their worn-out early SW-type locomotives. They determined it to be more cost-effective to remanufacture existing stocks of EMD SW7 and SW9's into what UP refers to as "SW10's."
The actual remanufacturing process was undertaken at UP's Omaha shops. Reconditioning entailed such items as replacement of original-equipment model 567 prime movers with rebuilt and upgraded 12-cylinder model 567BC engines rated at 1200 h.p. and model 645 components, installation of a state-of-the-art electrical system and moving the reconditioned radiator system from its customary position on the front of the unit to the locomotive's roof.
UP's SW10 offers modelers numerous opportunities to introduce their own element of "artistic license" into their modeling. SW10's can be found in many prototypical operating situations: yard switching, transfer service and passenger train switching - particularly that of Amtrak's California Zephyr/PioneerlDesert Wind at Salt Lake City - are some of the ways in which the units are deployed.
Modelers have several options insofar as providing themselves with a model of UP's SW10's is concerned. Those desiring to forego kitbashing plastic models will be pleased to know that a brass version has been imported by Overland Models in HO scale. For those whose budgets dictate against acquisition of the brass version, the most obvious scenario involves converting Athearn's SW1500 (SW7) into an SW10. Some major modifications to the Athearn unit include raising the forward hood section, installing GP7/9-type radiators on the upper left and right sides of the hood and adding new 36"-diameter cooling fans to the forward section of the roof. A new front-mounted sandbox would have to be fabricated and stanchions replete with railings would have to be installed. Study the accompanying photograph for correct placement locations. Very few modifications would be needed on the stock Athearn switcher chassis, with the possible exception of some added weight. Finally, the addition of detail parts, such as a modern "clean cab" interior by such firms as GSB would add considerably to the model's aesthetics.
Union Pacific's SW10 program solved a prototypical operational dilemma and it serves as a prime inspiration to modelers wanting to vary their switcher fleets by combining the best elements of new and old. It also virtually ensures that many familiar silhouettes will continue to populate the nation's railroads for some years to come.