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ALCO RS-1 - Savannah River Site No. 106

GCOX 106

No. 106 at the museum in 1997. Photo courtesy G Gerard.

Interesting facts

ALCO's RS-1 (the "RS" stands for "road switcher") had the longest production run of any U.S. built diesel-electric locomotive, although only 417 were built between 1941 and 1960.

The RS-1's carbody design, with its raised, offset cab to give engine crews better visibility, and its narrow hood with side walkways to facilitate train crew mobility, pioneered the road switcher type. Almost every road switcher built by ALCO and other manufacturers after its introduction followed this same basic design.

The first 13 production RS-1s, originally ordered by five U.S. Railroads, were requisitioned by the U.S. Army in 1942, re-manufactured by ALCO into 6-axle RSD-1s and shipped to the Trans Iranian Railroad to supply the Soviet Union as part of the Allied war effort during WWII.

GCOX 106

No. 106 at the museum in May 2010. Photo by Eric Kreszl.


No. 106 was built at the American Locomotive Company's Schenectady works in 1951 for the Savannah River Site, a 310 square mile nuclear facility located next to the Savannah River in South Carolina. The site was owned by the U.S. Atomic Energy Commission, although the facilities were built and operated by I. E. DuPont. The site is currently owned by the U.S. Department of Energy.

The site’s railroad operations stretched over 60 miles of track, with 4 RS-1s (Nos. 105-107) delivering materials within the site. The Classification Yard near the Dunbarton town site was responsible for operating the rolling stock and maintaining the tracks, which connected with the Atlantic Coast Line at Dunbarton and the Charleston & Western Railroad at Ellenton.

The Department of Energy donated No. 106 to the museum in 1989. We have repainted it as GCRM (Gold Coast Railroad Museum) 106.


An ALCO-GE advertisement for the 589T, the diesel
engine used in the RS-1. Image courtesy The
Tugboat Enthusiasts Society of the Americas.

The RS-1 was the product of a relatively shortlived partnership between the American Locomotive Company and General Electric Transportation Systems that lasted from 1940 to 1953. Under the joint arrangement, ALCO produced locomotive bodies and engines, and GE supplied the electrical gear.

GE had previously built electric locomotives in partnership with ALCO and Ingersoll-Rand beginning in the early 1900s. The partnership was formalized in 1923, and a series of diesel-electric boxcab switchers were also produced from 1924 (ALCO built the body, chassis and running gear, GE the generator, motors and controls, and Ingersoll Rand the diesel engine). ALCO dropped out of the arrangement in 1929 after acquiring the diesel engine manufacturer, McIntosh & Seymour, and went on to start its own line of diesel switchers. GE briefly continued working with Ingersoll-Rand and then, from 1931, started its own line of switchers.

Although then primarily a producer of steam locomotives, ALCO recognized the potential value of the diesel market. It produced a series of stock demonstrator models in 1931 and 1932, but was slow to capitalize on the emerging market: by 1940, it had produced just 187 diesel switchers, as well as 5 DL series passenger diesels. General Motors Electro Motive Division, by contrast, had over the same period built nearly 200 switchers, over 80 passenger cab units, 50 freight cab units, and 22 railcars, streamliner trainsets, and experimental locomotives. Baldwin Locomotive Works, working in partnership with Westinghouse, was also then joining the field with the first of its VO series switchers.

In this context, a new ALCO-GE partnership appeared to make sense. It was advertised as expert in the production of steam, electric, and diesel-electric motive power, and promised "the broad experience, the impartiality, and the equipment to give you the right power for each job." One of the first requests came from the Chicago, Rock Island and Pacific Railroad, seeking a multi-purpose unit that would take advantage of the diesel-electric's much greater availability than steam to alternate easily between passenger, branchline, switching, and road service. The result was the RS-1.

GCOX 106

No. 106 at the museum in April 2009. Photo by Eric Kreszl.

The new unit used the 1000 hp 539T engine frame from ALCO's DL series and S-2 switcher, but extended it by 8 feet 6 inches to allow a short hood to be added behind the cab to accommodate a steam generator for passenger service. The resulting 31 foot long frame had room for an 800 gallon under-frame water tank to feed the steam generator and, in the freight-only version, this tank could be used to augment the 800 gallon fuel tank beneath the cab floor.

The RS-1 was also the first ALCO unit to be equipped with General Steel Casting's B-trucks, later to become standard for ALCO general-purpose locomotives. To provide better stability, the trucks had a 9 foot 4 inch wheelbase, compared to the S-2's 8 foot span.

Soon after receiving an order for 2 units from the Rock Island, a similar request came from the Atlanta & St. Andrews Bay Railway. ALCO delivered 2 units to each railroad in March 1941, but take up from there was slow. By October 1942, when the nation's War Production Board requisitioned them for war service, only 13 RS-1s had been built or were in production.

GCOX 106

No. 106 at the museum in April 2009. Photo by Eric Kreszl.

During their second partnership, ALCO-GE developed the RS-1 to RS-3 series, the S-1 to S-5, RSD-1 to RSD-5, RSC-1 to RSC-2, and DL-105 to DL-305, but the relationship was sometimes strained. The final break in October 1953 probably reflected GE's growing conviction that it needed to be its own master if it was to compete effectively with the then dominant diesel manufacturer, EMD. It was clear that the future lay in the diesel road locomotive, but GE was apparently not convinced that ALCO would make the necessary investment to grow that market for the partnership.

Coincidentally, December 1953 saw the last ever steam locomotive built for a U.S.
mainline operator, 0-8-0 No. 244, outshopped by the Norfolk & Western Railway from its Roanoke, VA shops. ALCO had built its last steam locomotive, Pittsburgh and Lake Erie Railroad 2-8-4 No. 9406, in June 1948 although, by that time,
ALCO-GE had a respectable 40% of the diesel market. After GE terminated the arrangement, ALCO continued producing diesel-electrics, including the RS-1, buying electrical equipment from GE, although it was no longer GE's sole customer.

NdeM 8006

NdeM No. 8006, a GE UD18 in Mexico City, October 1975. Photo copyright
Raymundo Collada.

GE entered the diesel-electric market in 1956, with the 1800 hp UD18 unit, and its 1060 hp U9B appeared the following year, both similar in key design features to ALCO's offerings. Although all 23 were exported to South America, the competition was clearly hotting up!

In 1957, ALCO carried out a major plant modernization at Schenectady to facilitate diesel production. Part of the site was sold, a number of buildings were demolished, and new assembly lines were installed, but this was too little, too late. GE soon took the number two position from ALCO, and would eventually even surpass EMD in overall production.

Distracted by over-diversification and recurring labor troubles, struggling to maintain service standards with a reducing market sector, shrinking order book and falling profits, ALCO gradually succumbed to the competition, and its last production diesel-electric units were two T-6 switchers delivered to the Newburgh & South Shore Railway in Cleveland, OH in January 1969. The company finally left the market on December 31, 1969.

After locomotive production ceased, the designs, although not the engine development rights, were transferred to the Montreal Locomotive Works, ALCO's Canadian subsidiary originally purchased in 1904, which continued their manufacture. The diesel engine business was sold to the White Motor Corporation in 1970, which formed it into White Industrial Power. In 1977 White Industrial Power was sold to the British General Electric Company (not related to the U.S. General Electric), which renamed the unit Alco Power, Inc. The business was subsequently sold to the Fairbanks-Morse Corporation, which continues to manufacture ALCO-designed engines, in addition to its own designs. ALCO designs were also manufactured in Australia by A. E. Goodwin until 1972.

But, the diesel-electric locomotives ALCO built have been great survivors, and many still work on regional and tourist railroads across the United States and Canada. We still use No. 106 occasionally for yard work at the museum, and also have two other ALCOs in our collection: NASA S-2 No. 1, and Richmond, Fredericksburg & Potomac Railroad S-2 "C."

GCOX 106

No. 106 in the museum yard, December 2010.
Photo courtesy


Status: On Display, Restored, Operational.
Acquisition Date: 1989.
Built: ALCO 1951.
Serial: 79051.
Weight: 240,000 pounds.
Length: 54 feet 11 inches.
Height to Top Engine Hood: 12 feet 2 inches.
Height to Top of Cab: 14 feet 4 inches.
Horsepower: 1000.
Engine: 6L 4-cycle Model 539T.
Main Generator: GE-GT553
Auxiliary Generator: GE GMG144.
Traction Motors: Four GE 731.
Trucks: Two 4-Wheel.
Truck Wheelbase: 9 feet 4 inches.
Wheel Diameter: 40 inches.
Configuration: B-B.
Air Brake as Built: Westinghouse 6L.
Compressor: Westinghouse CD.
Starting Tractive Effort: 60,000 lbs @ 25%.
Continuous Tractive Effort: 34,000 lbs @ 8 mph.
Top Speed: 60 mph.

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