Milwaukee Road 760, an H-10-44 and the first FM locomotive, preserved in operating condition at Illinois Railway Museum.

(User:Slambo, CC BY-SA 2.5 <>, via Wikimedia Commons)


F-M logo.

FM H-10-44

The FM H-10-44 was a switcher locomotive produced by Fairbanks-Morse from August, 1944–March, 1950. The units featured a 1,000-horsepower (750 kW), six-cylinder opposed piston prime mover, and were configured in a B-B wheel arrangement mounted atop a pair of two-axle AAR Type A trucks, with all axles powered. Many H-10-44s received modifications that increased their horsepower rating to 1,200 hp (890 kW).

The Raymond Loewy-designed carbody featured a slanted nose, sloping hood lines, and (considered to be its most distinguishing feature) a protruding roof visor mounted on the rear of the cab. These styling cues were carried through to the H-10-44's successor, the FM H-12-44, until September 1952 when the exterior design was "Spartanized" to reduce production costs.

A total of 195 units were built for American railroads. Three intact examples of the H-10-44 are known to survive today, all of which are owned by railroad museums. Most notable of these is Milwaukee Road No. 760 (originally delivered as No. 1802), the first Fairbanks–Morse locomotive constructed in their own plant, which is preserved and operational at the Illinois Railway Museum. Another example is former Hallet Dock Company HD-11, which is now at the Lake Superior Railroad Museum in Duluth, Minnesota.

A reproduction H-10-44 locomotive sits atop the Wood Family Fishing Bridge, a former railroad bridge which crosses the Rock River several hundred yards south of the foundry where the H-10-44s were built, in Beloit, Wisconsin.


New York Central FM H-10-44 9109 at Cleveland, Ohio, September 28, 1960. Photographer: The Garys.

(Craig Garver from Tucson, Arizona, United States, CC0, via Wikimedia Commons)


Units produced

Railroad Quantity Road numbers Notes
Apache Railway 2 100, 200
Atchison, Topeka and Santa Fe Railway 3 500–502
Baltimore and Ohio Railroad 10 300–309 Renumbered 9700–9709
Chehalis Western Railroad (Weyerhaeuser) 2 492, 493
Chicago and North Western Railway 21 1036, 1048–1065, 1070, 1082
Chicago, Indianapolis and Louisville Railway (“Monon”) 1 18
Chicago, Milwaukee, St. Paul and Pacific Railroad (“Milwaukee Road’) 23 1802–1818, 1820–1825 Renumbered 760–776, 778–783; 760 (ex-1802), 767 (ex-1809) and 781 (ex-1823) are preserved in museums.
Chicago, St. Paul, Minneapolis and Omaha Railway (“Omaha Road”) 5 94–98
Columbia and Cowlitz Railway 1 D-1 to Pacific Great Eastern Railway
Denver and Rio Grande Western Railroad 4 120–123 122 to Frisco 286
Fairbanks-Morse (demonstrator unit) 1 10L45 to Milwaukee Road 1819; renumbered 777
Indianapolis Union Railway 9 10–18
Kentucky and Indiana Terminal Railroad 10 48–52, 55–59
Minnesota Western Railway 1 51 to Minneapolis, Northfield and Southern Railway 11, to Hallet Dock Company HD-11
New York Central (Pittsburgh and Lake Erie Railroad) 4 9100–9103
New York, Chicago and St. Louis Railroad (“Nickel Plate Road”) 9 125–133 to Norfolk and Western Railway 2125–2133
Pennsylvania Railroad 55 5980–5986, 5997–5999, 9080–9099, 9184–9196, 9288–9299 to Penn Central 8211-8265
Pittsburgh, Chartiers and Youghiogheny Railway 1 1
St. Louis-San Francisco Railway 12 270–281
Terminal Railroad Association of St. Louis 4 700–703
Union Pacific Railroad 5 DS1300–DS1304
Wabash Railroad 4 380–383 to Norfolk and Western 3380–3383
Weyerhaeuser Timber Company 1 481
Total 195

B&O 9207, an FM H10-44, near Riverside Yard, Baltimore, MD on January 19, 1969.

(Photo by Roger Puta, railfan 44, Public domain, via Wikimedia Commons)



Type and origin
Power type: Diesel-electric
Builder: Fairbanks-Morse
Model: H-10-44
Build date: August 1944–March 1950
Total produced: 195
​• AAR B-B
Gauge: 4 ft 8+1⁄2 in (1,435 mm)
Trucks: AAR type A
Wheel diameter: 40 in (1,016 mm)
Minimum curve: 29.50 (194 ft (59.13 m) radius)
Wheelbase: 33 ft 6 in (10.21 m)
Length: 48 ft 10 in (14.88 m)
Width: 10 ft 2 in (3.10 m)
Height: 14 ft 6 in (4.42 m)
Locomotive weight: 240,000 lb (108.9 t)
Prime mover: FM 38D-8 1/8
Engine type: Two-stroke diesel
Aspiration: Roots blower
Displacement: 6,222 cu in (101.96 L)
Generator: Westinghouse 481-A
Traction motors: (4) Westinghouse 362-D
Cylinders: 6 (Opposed piston)
Cylinder size: 8.125 in × 10 in (206 mm × 254 mm)
Locomotive brake: Straight air
Train brakes: Air
Performance figures
Maximum speed: 60 mph (97 km/h)
Power output: 1,000 hp (746 kW)
Tractive effort: 40,440 lbf (179.9 kN)
Locale: North America
Disposition: Three preserved, remainder scrapped, 1 replica on display


Hallett Dock Company No. 11 was built in 1946, shown here at the Lake Superior Railroad Museum in July of 2021.

(Znns, CC BY-SA 4.0 <>, via Wikimedia Commons)