EMD F45

The EMD F45 emerged from a collaborative relationship between General Motors' Electro-Motive Division and the Atchison, Topeka and Santa Fe Railway in the late 1960s. Santa Fe had already worked with EMD to produce the FP45, a full-width cowl-bodied passenger locomotive based on the SDP45, and subsequently requested a similar treatment for freight service. The result was essentially an SD45 fitted with the same wide-nose cowl carbody, designated the F45. Santa Fe ordered two groups of twenty units each for delivery in 1968, receiving them in the railroad's blue and yellow freight colors rather than the warbonnet scheme applied to the FP45s. The second batch was equipped with steam lines to allow them to serve as trailing units on passenger trains. The Great Northern Railway adopted the F45 for different reasons, recognizing that the enclosed cowl body would offer better protection for crews operating in the harsh winter conditions of the northern tier states. Great Northern ordered an initial six units for 1969 delivery, followed quickly by an additional eight before the first group had even arrived, and then twelve more intended for 1970 delivery. That final Great Northern order was ultimately fulfilled under Burlington Northern colors, as the merger creating that railroad occurred before the locomotives reached their intended owner. Burlington Northern placed one additional order of twenty units in 1971 before returning to the standard SD45 configuration for subsequent purchases. The F45's legacy extended well beyond its original service life through a series of notable rebuilding programs. Santa Fe's San Bernardino shops undertook a comprehensive rebuilding of their fleet between 1982 and 1983, emerging with units redesignated as SDF45s with electrical systems upgraded to SD45-2 standards. Morrison-Knudsen and its successor MotivePower found further use for the distinctive cowl bodies of scrapped Burlington Northern units, incorporating them into rebuilt locomotives for New Jersey Transit and Tri-Rail into the late 1980s. One former Santa Fe unit, after serving as an emissions test platform, has been preserved and is awaiting restoration, while another has been converted into a lodging accommodation at the Izaak Walton Inn in Essex, Montana.

The F45 was powered by the EMD 645E3 prime mover in its twenty-cylinder configuration, producing 3,600 horsepower and driving a Co-Co wheel arrangement through six traction motors. This placed the F45 in the same power category as the SD45 upon which it was mechanically based, differing principally in its full-width cowl carbody rather than the conventional hood unit configuration. The cowl body was not a structural load-bearing element in the manner of older cab unit designs but rather an aesthetic and functional shroud built over a conventional underframe, providing crew protection and a more streamlined appearance without fundamentally altering the mechanical layout underneath. When Santa Fe's units were rebuilt into SDF45s during the early 1980s, the opportunity was taken to address gearing as well as electrical systems. The original 59:18 gear ratio, which permitted a top speed of approximately 89 miles per hour, was changed to a 60:17 ratio reducing maximum speed to around 83 miles per hour, better suiting the locomotives to heavy freight service. A subsequent re-gearing to 62:15 reduced the top speed further to approximately 71 miles per hour. The electrical upgrades brought the rebuilt units to SD45-2 standards, reflecting improvements in control and performance technology that had been introduced in the intervening years since original construction.

Models by: Athearn