Special Duty and Specialized Duties

Posted by George Hamlin
on Friday, January 15, 2021

By the late 1960s, the U.S. intercity passenger train was in exremis in a variety of ways.  Its traffic base had been decimated by both the Interstate Highway System and the airline industry with its (then) relatively-new jet aircraft.  Heavy losses weighed on many railroads’ finances.  The equipment, including new passenger cars and diesel locomotives acquired in the post-World War II euphoria were wearing out, and needed to be replaced, in many cases.

Beyond the acquisition of the 1956 Denver Zephyr passenger cars, Santa Fe’s high-levels for the El Capitan, and the one-off “tubular” Keystone for the Pennsylvania, new intercity passenger car orders had essentially ceased.  On the locomotive front, the carbody-format EMD E and F units were clearly on the way out; new freight motive power consisted of “second-generation” hood units.  As for Alco PAs and FAs, as of 1969, their manufacturer had exited the business entirely, at least in the U.S. 

Thus, prior to the planning for what became Amtrak, a logical process was invoked, meaning that both EMD and relative-newcomer General Electric offered “passenger” versions of some of their late-model freight motive power.  In GE’s case, this produced the small fleets of U28/U30CGs acquired by the Santa Fe; only the ATSF participated in this exercise.

EMD offered the SDP35, essentially its SD(“Special Duty”)35 with a steam generator; this was acquired by Atlantic Coast Line (a single example); Seaboard Air Line; Louisville & Nashville (which promptly put them in freight service) and the Union Pacific.  When the 645 prime mover (diesel engine) supplanted the 567, the horsepower was upped, producing the SD40 on the freight side, along with the SDP40, which was ordered by the Great Northern and NdeM in Mexico.  Subsequently, to go along with the SD45, the SDP45 was introduced, selling to the GN (eight units) and the Southern Pacific (ten locomotives).

None of these could be judged to have been a notable success for their original purpose, mainline limiteds, in part due to the railroads’ accelerating success in shedding intercity passenger service in the latter part of the ‘60s.  Prior to Amtrak, EMD did produce something of a little more note, in the form of a “cowl” unit, the FP45, specifically for use on the ATSF's still-premium Super Chief/El Cap; these were run together with F45s (which lacked the “P” version’s steam generators), and the Milwaukee Road also acquired five FP45s for its remaining intercity trains.

The F45 was the most successful of this breed, with 86 total built, for the Santa Fe, Great Northern and eventually, the GN’s successor, the Burlington Northern.  Once Amtrak arrived, virtually all the remaining locomotives of this locomotive genre (cowl and standard cab) were retained by their owners for freight service; interestingly, the ATSF’s FP45s lasted long enough to be repainted into their original “Warbonnet” red and silver colors in 1989, when the railroad initiated what it termed its “Super Fleet” for premium intermodal service.

The exception to this trend was the SP’s fleet of SDP45s.  By the early 1970s, the railroad needed a replacement for the Fairbanks-Morse H24-66 “Train Masters” that formed the backbone of its San Francisco Bay area “Commute” services, and dated from the mid-1950s.  The SDPs would soldier on, still using their steam-heat boilers, until replaced in the mid-1980s by EMD F40PH locomotives (an Amtrak-era four-axle cowl unit) ordered by the State of California.  Thus, these locomotives were the only examples of the “replacement” power discussed here that spent virtually all of their careers in passenger service, as originally intended, albeit of a quite different sort than what they were acquired for.

And while they no longer powered the likes of the Daylight, I am very confident that SP 3201, seen above at San Francisco on April 19, 1982, knew the way to San Jose very well, indeed.

(Photo by George W. Hamlin)

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