EMD FP45

The EMD FP45 emerged in 1967 as a direct response to a request from the Atchison, Topeka and Santa Fe Railway, which operated some of the most celebrated passenger trains in the United States, including the Super Chief and El Capitan. Santa Fe's management was dissatisfied with the workmanlike appearance of conventional hood unit locomotives, whose external walkways and utilitarian lines they considered inappropriate for prestigious passenger service. EMD had already developed the SDP45, which performed well mechanically in that role, but the Santa Fe pushed for a more refined external appearance. The solution was a cowl body design that enclosed the locomotive's mechanical components in a smooth, aerodynamically shaped shell, giving the FP45 a visual character closer to the earlier cab unit locomotives that had long defined American passenger train aesthetics. Production of the FP45 was quite limited by any measure. Santa Fe took delivery of nine units, numbered 100 through 108, while the Chicago, Milwaukee, St. Paul and Pacific Railroad purchased five additional examples, numbered 1 through 5, for use on its own passenger operations. The Milwaukee Road's units were delivered without dynamic brakes. Illinois Central reportedly explored acquiring five FP45s as well, but that order was ultimately canceled. With only fourteen locomotives built in total, the FP45 represented one of the smaller production runs in EMD's catalog, though the model was financially viable because it shared its fundamental mechanical underpinnings with the more widely produced SDP45. The FP45's service career extended well beyond the passenger era that inspired it. After Santa Fe discontinued its passenger operations, the surviving units were repurposed and rebuilt. Between 1980 and 1982, Santa Fe's San Bernardino shops overhauled eight of the locomotives, upgrading them electrically to SD45-2 standards and re-gearing them for freight service. These rebuilt examples were redesignated SDFP45s and continued working through the final years of the Santa Fe before its merger with Burlington Northern in 1995, after which the remaining units were retired. The Milwaukee Road's five FP45s met an earlier end, with all five sold for scrap between 1981 and 1984. Several Santa Fe examples survived into preservation, with restored or display specimens held at museums across the United States, including the Illinois Railway Museum, the Southern California Railway Museum, and the Great Plains Transportation Museum.

The FP45 rode on a Co-Co wheel arrangement, meaning it carried two three-axle powered trucks, the same configuration used on the SDP45 from which it was derived. Power came from an EMD 20-cylinder 645E3 prime mover producing 3,600 horsepower, and the final drive gear ratio for passenger service was set at 57:20. The cowl body that defined the FP45's appearance was not a structural element in the way that earlier cab unit carbodies had been. Instead, the locomotive's frame carried the structural loads, and the cowl served purely as an enclosure, providing aerodynamic benefit at speed and allowing crew members to move through the engine compartment while underway for inspection and maintenance purposes. This approach simplified construction and made the cowl body a cost-effective styling solution rather than a fundamental engineering departure. During the SDFP45 rebuild program carried out at San Bernardino, the locomotives received electrical upgrades bringing them in line with SD45-2 standards, and their gearing was changed from the original 59:18 ratio to 60:17, which reduced maximum speed from approximately 89 miles per hour to 83 miles per hour. Later in the mid-1980s, Santa Fe re-geared the fleet again to a 62:15 ratio, further reducing top speed to approximately 71 miles per hour, reflecting their full transition to freight service where sustained high speed was less critical than tractive effort and operational flexibility.

Models by: Athearn · Walthers