EMD FP7

Infobox Locomotive
name=EMD FP7
powertype=Diesel-electric


caption=SSW ("Cotton Belt") #306 at St. Louis, Missouri, 1953
gauge=RailGauge|ussg|lk=on
builder=General Motors Electro-Motive Division (EMD)
General Motors Diesel (GMD, Canada)
buildmodel=FP7
length=convert|54|ft|8|in|m|2|abbr=on
primemover=EMD 567
cylindercount=V16
poweroutput=convert|1500|hp|kW|abbr=on|lk=on
aarwheels=B-B
builddate=June 1949 – December 1953
totalproduction=378The EMD FP7 was a convert|1500|hp, B-B dual-service passenger and freight-hauling diesel locomotive produced between June 1949 and December 1953 by General Motors' Electro-Motive Division and General Motors Diesel. Final assembly was at GM-EMD's La Grange, Illinois plant, excepting locomotives destined for Canada, in which case final assembly was at GMD's plant in London, Ontario. The FP7 was essentially EMD's F7A locomotive extended by four feet to give greater water capacity for the steam generator for heating passenger trains.

While EMD's E-units were successful passenger engines, their A1A-A1A wheel arrangement made them less useful in mountainous terrain. Several railroads had tried EMD's F3 in passenger service, but there was insufficient water capacity in an A-unit fitted with dynamic brakes. The Atchison, Topeka and Santa Fe Railway's solution was to replace the steam generators in A-units with a water tank, and so only fitted steam generators in to the B-units. The Northern Pacific Railway's solution was to fit extra water tanks in to the first baggage car, and to pipe the water to the engines. The real breakthrough however, came when EMD recognized the problem and added the stretched, custom-built FP7 to its catalog.

A total of 378 cab-equipped lead A units were built; unlike the freight series, no cabless booster B units were sold. Regular F7B units were sometimes used with FP7 A units, since they, lacking cabs, had more room for water and steam generators. The FP7 and its successor, the FP9, were offshoots of GM-EMD's highly successful F-unit series of cab unit freight diesels.

It is important to note that F3s, F7s, and F9s equipped for passenger service are "not" FP-series locomotives, which although similar in appearance have distinctive differences, including but not limited to the greater body length.

The extra convert|4|ft|m|abbr=on of length was added behind the first body-side porthole, and can be recognised by the greater distance between that porthole and the first small carbody filter grille. The corresponding space beneath the body, behind the front truck, was also opened up; this either remained an empty space or was filled with a distinctive water tank shaped like a barrel mounted transversely.

Original buyers

Locomotives built by EMD at La Grange, Illinois

Locomotives built by GMD at London, Ontario

Preserved examples

*Chicago Great Western Railway 116A, on display, at Hub City Heritage Railroad Museum, Oelwein, Iowa.
*Reading 902, in operating condition.
*Reading 903, in operating condition.
*Soo Line 500A (né EMD demonstrator #9051), on display at Ladysmith, Wisconsin.
*Soo Line 2500A (né EMD demonstrator #7001), restored to working condition, at Lake Superior Railroad Museum, Duluth, Minnesota.
*Southern Railway (of the United States) No. 6133, in working condition at the North Carolina Transportation Museum at Spencer, North Carolina.
*Verde Canyon Railroad in Clarksdale, Arizona uses two FP7s (1510 and 1512) to haul its excursion train.
*Western Pacific 805-A, a locomotive used on the famous "California Zephyr", is preserved in operable condition at the Western Pacific Railroad Museum at Portola, California.
*R J Corman operates two of the ex-Southern units on its Kentucky Dinner Train operation out of Bardstown, KY.

References

* " [http://users.inna.net/~jaydeet/fp7.htm EMD's FP7 - Original Owners] ". Retrieved on January 4, 2005.
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