FM "H12-44" Locomotives

The H12-44 was Fairbanks Morse's most successful diesel locomotive, with nearly 400 constructed over an eleven year period.

While FM featured an opposed-piston prime mover that some railroads found complicated, the company's products were nevertheless rugged machines and quite reliable when understood by maintenance personnel.

This particular model looked quite similar to its predecessor, the H10-44, save for a slight increase in horsepower. While FM was able to sell a number of diesels through its Canadian Locomotive Company arm, it had difficulty finding sales in Mexico and outside of North America.

As it turned out, the H12-44 had one of the longest production runs of any FM model and so many were produced that at least sixteen domestic examples remain preserved today.

"September, 1969: At San Francisco's 4th & Townsend Depot Southern Pacific H12-44 #2351 has pulled the cars from cars having arrived on that afternoon's Train #99, "The Coast Daylight", from Los Angeles. By that time normal practice was to bring #99 in on Track 14, cut off the power so it could run light to the 7th & Townsend engine terminal. The depot switcher would pull the cars across 3rd then back them down King Street to the coach yard. As an aside, track #14 was the only track that ran past the depot. Today, with the possible exception of buildings in the distant back ground, everything in this photo no longer exists." - Drew Jacksich

H12-44 History And Background

The H12-44 began production during May of 1950 following the earlier H10-44. Railroads liked this switcher and were even happier with the additional 200 horsepower found in its successor.

The H12-44 was equipped with Fairbanks-Morse's standard 2-cycle, 38D8 1/8 opposed piston prime mover that could produce 1,200 horsepower using B-B trucks.

The carbody styling was again inspired by noted industrial designer Raymond Loewy.  However, to reduce production costs, FM simplified the design in the fall of 1952 removing many of the styling features Loewy had suggested.

It did not really take away from the model's attractiveness although the locomotive did sport a more basic, boxy appearance.

The FM H12-44 carried roughly the same tractive effort as its predecessor, and similar models in production by Alco and Electro-Motive.

Yankeetown Dock Corporation H12-44 #2 is seen here in Lynnville, Indiana on July 26, 1980. The FM switcher began its career with the company in 1956, one of two Yankee owned. Doug Kroll photo.

Thanks to the locomotive's relatively light-weight the H12-44 was ideal for use in both yard/switcher service and could also be used in light freight service with its respectable horsepower rating. 

FM's classification system somewhat resembled Baldwin's initial system, although somewhat more simplified. In regards to the H12-44:

  • "H" stood for Hood

  • 12" was for 1,200 horsepower

  • Each 4 meant four axles and four traction motors
Norfolk & Western H12-44 #3385 (ex-Wabash #385) switches train #111, the "Banner Blue," at Decatur, Illinois on May 7, 1966. Roger Puta photo.

Overall the locomotive sold 501 units in the U.S., and other 30 in Canada, by the time production had ended in March of 1961.  These 531 locomotives made the H12-44 FM's most successful model.

The Santa Fe certainly liked the switcher as the company wound up with 59 examples employing them heavily in light duty work.

Generally, FM models sold relatively poorly although it is not necessarily because Fairbanks Morse's design was unreliable as historical texts often mention.

Once the FM O-P engine was well understood by maintenance departments it was quite reliable in service.

For instance, in regards to the H24-66 "Train Master," it has been noted by John Kirkland in his book The Diesel Builders Volume 1 that the locomotives performed admirably for more than 20 years on the Southern Pacific.

This was due to a maintenance team that understood the model, despite taking a daily beating in freight service (and later in commuter assignments around the Bay Area).

In any event, the H12-44 was purchased by a little more than a dozen Class I systems including industries Ayrshire Collieries, U.S. Steel - Fairless Works, Yankeetown Dock, and the Tennessee Valley Authority.

Even the U.S. Army bought the locomotive, 20 to be exact! FM's Canadian arm also built 30 for Canadian National Railway as well as an A1A-A1A design known as the H12-46. CN ultimately wound up with 30 examples of the variant built during the early 1950s.

H12-44 Data Sheet

Entered Production5/1950 (Milwaukee Road #1826-1827)
Years Produced5/1950 - 3/1961
Fairbanks-Morse ClassH12-44
Engine38D8 1/8, 6-cylinder Opposed-Piston
Engine BuilderFairbanks-Morse
Carbody StylingRaymond Loewy
Length (Inside Couplers)48' 10"
Height (Top Of Rail To Top Of Cab)14' 6"
Width10' 2"
Weight240,000 Lbs
TrucksGSC Rigid Bolster, Drop-Side Equalizer
Truck Wheelbase8'
Wheel Size40"
Traction Motors362D (4), Westinghouse
Traction Generator481F, Westinghouse
Auxiliary GeneratorYG42A, Westinghouse
MU (Multiple-Unit)Yes
Gear Ratio68:14
Tractive Effort34,000 Lbs at 9 mph
Top Speed60 mph

H12-44 Production Roster (FM)

Owner Road Number Construction Number Contract Number Completion Date
Milwaukee Road1826-182712L374-12L375LD955/1950
Chicago & North Western1071-107212L376-12L377LD945/1950
New York Central911112L378LD9411/1950
New York Central9112-911812L379-12L385LD9212/1950
New York Central9119-912012L386-12L387LD921/1951
Santa Fe503-50412L388-12L389LD979/1950
Santa Fe505-50612L390-12L391LD9710/1950
Baltimore & Ohio310-31912L392-12L401LD1032/1951
Kentucky & Indiana Terminal Railroad60-6112L402-12L403LD1113/1951
Kentucky & Indiana Terminal Railroad62-6412L404-12L406LD1114/1951
Minnesota Western Railroad (Minneapolis, Northfield & Southern)1012L427LD1041/1951


  • Kirkland, John F. Diesel Builders, The:  Fairbanks-Morse And Lima-Hamilton. Glendale: Interurban Press, 1985.

  • Pinkepank, Jerry A. Diesel Spotter's Guide.  Milwaukee: Kalmbach Publishing Company, 1967.

  • Schafer, Mike. Vintage Diesel Locomotives. Osceola: MBI Publishing, 1998.

Milwaukee Road H12-44 #718 carries out switching chores at the railroad's new station in Milwaukee, Wisconsin on August 28, 1966. Roger Puta photo.

It should be noted that another variant was manufactured as well, the H12-44TS for the Santa Fe numbered 541, 542, and 543.

The AT&SF requested the locomotive for use in shuttling passenger trains and equipment around its Dearborn Station terminal in Chicago.

The locomotive was somewhat longer at 54 feet, 2 inches and featured the addition of a short hood ahead of the cab giving it the appearance of a road switcher.

However, it still offered 1,200 horsepower and a B-B truck arrangement. Santa Fe regularly employed the three units in yard service until 1972 when the were sold. 

Today, #543 is preserved at the Illinois Railway Museum. In any event, a photo of 543 is presented below pushing the Super Chief into Dearborn Station on October 14, 1972. 

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Header Photo: Drew Jacksich

Wes Barris's is simply the best web resource in the study of steam locomotives. 

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A popular pastime for many is studying and/or exploring abandoned rights-of-way. 

Today, there are tens of thousands of miles scattered throughout the country.  Many were pulled up in the 1970's and 1980's although others were removed long before that. 

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