The Alco RS3

The Alco RS3 was the builder's pinnacle in its early road switcher designs. While the American Locomotive Company would have some success in later Road Switcher (RS) series models, like the RS11 and RSD5, nothing would compare to the amazing success of the RS3.  When it was released Alco had already cataloged two previous versions, the RS1 and RS2, both of which had seen modest success as the first true road-switchers ever produced. Unfortunately, overall the Schenectady manufacturer had considerable trouble seriously competing with Electro-Motive whose cab designs were far outpacing anything in its catalog. In any event, the RS3 would go on to be the most commonly seen Alco model across the country and remained in the company's catalog for more than six years. Today, numerous examples of this locomotive remain preserved, several of which are still operational.

Rock Island RS3 #488 is seen here at the Joliet, Illinois terminal by itself on August 23, 1964.

The Alco RS3 entered production in 1950 replacing its predecessor the RS2. The new model produced slightly more horsepower than the earlier design at 1,600 hp using Alco's commonly problematic 12-cylinder, model 244 prime mover.  From a visual standpoint the RS3 looked almost identical to the RS2. Both had much improved styling over the RS1 albeit it was quite subtle with heavy beveling to corners and edges giving the unit a much more streamlined appearance (because of its good looks some railroads elected to employ theirs in passenger/commuter service).  Instantly beloved by railroads for its versatility and reliability, RS3s began rolling out of Alco's Schenectady shops in the masses.

Erie Lackawanna RS3 #1008 brightens up a rather overcast day in Hammond, Indiana on Apirl 2, 1971. This unit was built as Erie #1008 in 1950 and later went on to Conrail.

Perhaps more than any other locomotive the RS3 defined Alco as a locomotive manufacturer offering eye-appealing, classy designs with their trademark belching black smoke.   While the RS1 and RS2 had sold relatively well perhaps it was the RS3's extra 100 horsepower over its predecessor that really appealed to railroads.  While the model 244 proved generally reliable and rugged in its smaller switcher and light road switcher designs (like the RS3) the prime mover simply not been properly researched and developed for heavy-haul use.  As such, the FA and PA models in production at the time experienced significant mechanical issues.  This allowed Electro-Motive to gain a notable edge and these problems ultimately resulted in Alco's exit from the market.

Amtrak RS3 #129 switches a pair of E8As in Chicago on June 16, 1977. This unit began its career as New York Central #8268 in June of 1951.

Interestingly, a year prior to the RS3's release EMD was finally cataloging a competitor, the GP7. Unfortunately for EMD their initial design, the BL2, proved unsuccessful although the industry leader quickly learned from their mistake. The model used the same road switcher design setup pioneered by Alco in its 1941 RS1 with a long trailing hood, offset cab, and short front hood.   Both as the time as well as from a historical stance the RS3 has been deemed an incredible success for Alco. However, had the builder acquired the reputation of EMD it may have sold even more.  The GP7 went on to sell more than 2,700 examples before its production run ended in 1954 and its successor, the GP9, was even more successful.

When the RS3 was produced Alco was still working in conjunction with General Electric and Westinghouse to supply internal components for its locomotives. As such the model contained air brakes and compressors from the latter while the former provided its model 752 traction motors that gave the RS3 around 60,000 pounds of initial tractive effort (more than 2,000 more than the RS2). The model weighed around 114.5 tons, was 55 feet/5 inches in length and equipped with dynamic braking. This latter ability allowed railroads to use the RS3 in heavy-haul service, such as moving coal drags up steep grades and many did not shy away from doing so; for instance the Reading, Lehigh Valley, Louisville & Nashville, Southern and others beat theirs to pieces in this capacity.

Erie Lackawanna RS3 #1042 leads a freight through Hammond, Indiana during March of 1964.

It was the model's ability to take this abuse regularly and continue operating on a daily basis that so endeared them to railroads and resulted in many returning to Alco for more.   It's a shame that the company could not have produced other locomotives that emulated the success of the RS3. By the time production ended in 1956 Alco would sell more than 1,300 and even today you can still find these venerable locomotives operating on short lines and tourist trains all across the country. Most interesting is that when Alco introduced its RS line in 1941and found success with a locomotive that could be used in multiple roles EMD was convinced to begin manufacturing its own line of road switcher that would eventually help put Alco out of business one day.

Production Roster Of Alco RS3s

Owner Road Number(s) Quantity Date Built
Alco Demonstrator1600-1601, 160731950, 1952
Alton & Southern43-4531950-1956
American Smelting & Refining2-321950
Atlantic & Danville10711951
Birmingham Southern151-15221950-1951
Blue Ridge Railway1-221950
Boston & Maine1505-1519, 1535-1545261952-1954
Carolina & North-Western5, 1021950, 1953
Central Of Georgia108-119, 133-159391950-1953
Central Railroad Of New Jersey1540-1555, 1700-1709261950-1953
Central Vermont1859-186021954
Chesapeake & Ohio5600-560121955
Chicago & North Western1551-1555, 1613-1624171951-1953
Cincinnati, New Orleans & Texas Pacific (Southern)6208-6239321952
Chicago, St. Paul, Minneapolis & Omaha (C&NW)162-16761952-1953
Danville & Western1-221950
Delaware & Hudson4026-41291041950-1953
Delaware, Lackawanna & Western (Lackawanna)901-918181950-1952
Denver & Rio Grande Western5200-520451951
Erie914-933, 1005-1038541950-1952
Federal Barge Lines60-6121952, 1955
Grand Trunk Western1861-186221954
Great Northern197-199, 220-224, 228-232131950-1953
Green Bay & Western305-30841951, 1955
Gulf, Mobile & Ohio1515-152391950-1952
Interstate Railroad30-36, 38-3981953, 1956
Kennecott Copper10911950
Lake Superior & Ishpeming1604-161071950-1955
Lehigh & Hudson River1-13131950-1951
Lehigh Valley215-21621950
Litchfield & Madison301-30331952-1956
Long Island Rail Road1551-1560101955
Louisville & Nashville100-154, 170-179, 214-2551071951-1956
Macon, Dublin & Savannah1703-170641950-1956
Maine Central556-55721953
Milwaukee Road2475-2495211953-1955
Minnesota Transfer200-20121951
Missouri-Illinois Railway19-20, 62-74151951-1955
Missouri-Kansas-Texas (Katy)1551-1563, 1701-1702151950-1951
Missouri Pacific4501-4526261955
New Haven517-561451950-1952
New Orleans & Northeastern (Southern)6875-688281950
New York Central8223-83521301950-1953
Nickel Plate Road535-557231954
Norfolk & Western300-30781955-1956
Northern Pacific850-863141953-1955
Oliver Iron Mining1108-111031950
Pennsylvania8435-8484, 8590-8605, 8817-8856, 8902-89161211951-1955
Piedmont & Northern100-109101950-1951
Pittsburgh & Lake Erie (NYC)8353-835751953
Reading444-475, 481-524761951-1953
Rock Island455-474, 485-499251950-1951
Rutland201-20881951-1952
Soo Line352-35321954
St. Louis Southwestern (Cotton Belt)308-310, 311 (1st/2nd), 312-318, 356-360171951-1952
St. Marys Railroad501-50221951, 1956
San Manuel Copper1-331955
Seaboard Air Line1629-1684561950-1952
Southern2025-2062, 2131-2145531951-1953
Spokane, Portland & Seattle65-82, 90-98271950-1955
Tennessee Central251-260101950-1956
Terminal Railroad Association of St. Louis (TRRA)1600-160341950
Texas Pacific-Missouri Pacific Terminal2411956
Toledo, Peoria & Western20711950
Western Maryland185-198141953-1954
Yadkin Railroad911951


Northern Pacific RS3 #863 is seen here near the road's northern terminus of International Falls, Minnesota during early August of 1966.

Of note, Alco's Canadian arm, the Montreal Locomotive Works, was not nearly as successful with the RS3 selling just 98 to the Canadian National, Canadian Pacific, Ontario Northland, Pacific Great Eastern, Quebec, North Shore & Labrador, and the Roberval & Saguenay.  Additionally, Alco built another 69 units for foreign sale including the Algerian Railways, Central do Brazil, Consolidated Railways of Cuba (before trade bans with Cuba were enacted), Ferrocaril del Pacifico, and National de Mexico (the above production roster includes only domestically sold RS3s).  From the historical narrative it is fascinating that it was Alco, not EMD, which pioneered the endearing locomotive design still regularly used in freight service today; the common road-switcher.

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A History Of The American Locomotive Company (Alco)




A History Of The Montreal Locomotive Works (MLW)


Other Alco Road-Switcher Models



The RS1




The RSD1




The RS2




The RSC2




The RSD4




The RSD5




The RSD7




The RS11




The RSD12




The RSD15




The RS27




The RS32




The RS36


Alco's Notable Prime Movers



The Model 244




The Model 251