EMD GP59

The EMD GP59 was produced by General Motors Electro-Motive Division between 1985 and 1989 as a mid-range road switcher intended to offer solid performance in a package less powerful than the top-tier locomotives of the era. A total of 36 units were constructed, a figure that includes three demonstrator locomotives built to showcase the model to prospective buyers. Despite EMD's efforts to market the type more broadly, Norfolk Southern Corporation proved to be the only railroad to place a production order, and the railroad subsequently acquired all three demonstrators as well, making it the sole operator of the GP59 anywhere in the world. Norfolk Southern's exclusive ownership of the GP59 fleet gave the model an unusual place in diesel locomotive history, as its entire production run ended up in the hands of a single carrier. The three demonstrator units featured an aerodynamic cab design that distinguished them somewhat from the production locomotives. Though the GP59 never achieved widespread adoption, it served Norfolk Southern reliably enough that the railroad invested in a substantial rebuilding program beginning in 2011. The first completed example of the upgraded variant, designated the GP59E and numbered NS 4650, was not released until March 2013. These rebuilt locomotives received a range of modernized systems and represented a significant commitment to extending the useful life of the fleet. In 2016, Norfolk Southern expanded its rebuilding efforts by launching a program to produce units designated GP59ECO. Unlike some contemporaneous locomotive upgrade programs that relied on government funding, Norfolk Southern financed these rebuilds independently. The first GP59ECO, numbered 4662, was completed in June 2016 and was rebuilt from a GP50 unit rather than an original GP59, reflecting the flexibility of the upgrade platform. The GP59ECO program drew on concepts similar to those used in EMD's GP33ECO rebuilds and demonstrated Norfolk Southern's continued willingness to invest in locomotive modernization rather than wholesale fleet replacement.

The GP59 is powered by a 12-cylinder EMD 710G3A prime mover producing 3,000 horsepower, placing it in a middle tier of output among EMD's road switcher offerings of the period. The locomotive rides on a B-B wheel arrangement, meaning two two-axle trucks, and employs a conventional DC traction system. One notable aspect of the GP59's construction is that it shares its frame with the more powerful EMD GP60, giving it an overall length of approximately 59 feet 9 inches. The fuel tank holds roughly 3,700 US gallons, providing adequate range for road service assignments. The GP59E rebuild program introduced a substantial suite of upgrades to the original design. Rebuilt units received an EM2000 microprocessor, a redesigned electrical cabinet incorporating SmartStart automatic start and stop functionality, and a rebuilt 12-710G3C-BC prime mover equipped with the EMDEC electronic unit injector system. Norfolk Southern also incorporated its own split cooling arrangement and fitted the rebuilt locomotives with the NS Admiral cab, which includes cab signals, locomotive speed limiter functionality, and a CCB26 electronic brake valve. The GP59E units were additionally configured to work in conjunction with Norfolk Southern's RP-M4C road slugs, enhancing their tractive effort capabilities in demanding service conditions.

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