Alco "RS1" Locomotives: Roster, Specs, Data Sheet

Last revised: December 27, 2024

The American Locomotive Company (Alco) could seemingly never outdo the Electro-Motive Division for dominance in the early diesel locomotive market.

Despite this, the company would develop one of the most important layouts for how all future diesel locomotives would be built; the RS1, which pioneered the original road-switcher design.

Not only would EMD go on to use the carbody style in its later General Purpose (GP) series but also the offset cab layout is still used today by General Electric and successor Electro-Motive Diesel.

The RS1 was in production longer than any other model at the time, remaining in Alco's catalog for nearly 20 years. Today, you can still find a handful of these rugged workhorses preserved at various museums around the country - some of which are even still operational.

Photos

It's the early Penn Central era as a former Pennsylvania RS-1 lays over in Bristol, Pennsylvania along the Northeast Corridor during the spring of 1968. Photographer unknown. American-Rails.com collection.

The RS1 was released by the builder in early 1941; it was the first in a long line of Road Switcher models that ended in 1963 with the RS36. It is also recognized as the first, true road-switcher ever cataloged by a locomotive manufacturer. Alco's history with its early, cataloged diesel switchers dated all of the way back to its demonstrator HH300 models (High Hood) of the early 1930s.

Pennsylvania RS1 #9919 at Meadows Yard in Kearny, New Jersey, circa 1967. Fred Byerly photo. American-Rails.com collection.

However, the company's history with diesel locomotive technology goes back even further to a testbed switcher outshopped in July, 1925 in conjunction with General Electric and Ingersoll-Rand. In his book, "The Diesel Builders, Volume Two: American Locomotive Company and Montreal Locomotive Works," author John Kirkland notes this 300 horsepower, 60-ton unit was completed as Alco order S1484, construction number 65979.

The early "HH" series models were essentially prototypes themselves, built in conjunction with Westinghouse and McIntosh & Seymore, and sold to a handful of railroads. Interestingly, as Kirkland points out, Alco never actually cataloged these switchers as "High Hood," designs. This was yet another term later coined by railfans.

St. Louis-San Francisco Railway RS-1 #105, sub-lettered for subsidiary Alabama, Tennessee & Northern, is seen here in Springfield, Missouri, circa 1965. Mac Owen photo. American-Rails.com collection.

The RS1, a design requested at the behest of Rock Island's chief operating officer, J.D. Farrington for use in passenger service along its lightly populated branch lines in the Midwest. In addition to passenger assignments consisting of only one or two cars, railroads soon found the RS1 could handle both light freight duties and switching assignments.

The RS1 was given slight design features from famed industrial designer Otto Kuhler. Most noteworthy is that they were the first to employ raised cabs for better visibility, so commonly employed in today's locomotives. Designed by Westinghouse as the "visibility cab", they were normally wider and taller than the engine hood providing crews with better visibility featuring an arched roof line.

Spokane, Portland & Seattle RS1 #54 at Portland, Oregon; August, 1965. Fred Byerly photo. American-Rails.com collection.

As such, it featured a long hood to house the 539T power plant, a McIntosh & Seymore with a cab was placed offset on the frame. This setup gave the locomotive a short hood at one end, used to house a steam generator for passenger service.

Data Sheet and Specifications

1941-1942

Alco Class	404-DL-240
Entered Production	3/14/1941
Years Produced	3/1941-6/1942
Model Specification	E1640
Engine	539T, 6-Cylinder In-Line, Turbocharged
Engine Builder	Alco/McIntosh & Seymour
Horsepower	1,000
Carbody Styling	Alco
Length (Between Coupler Faces)	55' 11 ¾"
Height (Top of Rail to Top of Cab)	14' 6"
Width	10' 0"
Weight	240,000 Lbs
Dynamic Brakes	Yes
Air Brake Schedule	14EL
Trucks	B-B
Truck Type	Swing Bolster, Drop-Side Equalizer (AAR Type-B)
Wheelbase	9' 4"
Wheel Size	40"
Traction Motors	GE 731 (4)
Traction Generator	GT533
Gear Ratio	75:16
Tractive Effort Rating (Starting)	72,000 Lbs (at 30% adhesion)
Tractive Effort Rating	34,000 Lbs at 8 MPH
Top Speed	60 MPH

Post World War II

Alco Class	404-DL-240
Entered Production	3/14/1941
Years Produced	1945-11/1957
Model Specification	E1641/A
Engine	539T, 6-Cylinder In-Line, Turbocharged
Engine Builder	Alco/McIntosh & Seymour
Horsepower	1,000
Carbody Styling	Alco
Length (Between Coupler Faces)	55' 11 ¾"
Height (Top of Rail to Top of Cab)	14' 6"
Width	10' 0"
Weight	240,000 Lbs
Dynamic Brakes	Yes (Optional)
Air Brake Schedule	14EL
Trucks	B-B
Truck Type	Swing Bolster, Drop-Side Equalizer (AAR Type-B)
Wheelbase	9' 4"
Wheel Size	40"
Traction Motors	GE 731D (4)
Traction Generator	GT553A
Gear Ratio	75:16
Tractive Effort Rating (Starting)	72,000 Lbs (at 30% adhesion)
Tractive Effort Rating (Continuous)	34,000 Lbs at 8 MPH
Top Speed	60 MPH

Prior to the start of World War II there were thirteen RS1's produced for five different railroads. Please refer to the table below. These locomotives were later requisitioned by the U.S. Army for use on the Trans-Iranian Railway to supply Russia with war materiel during the conflict.

The locomotives were based out of the Port of Bandar Shahpur on the Persian Gulf, running 685 miles largely through an arid, desert environment before entering elevations of 7,000 feet.

The Army had Alco retrofit the units with tapered cabs and change the roof line to meet tunnel clearances. In addition, the B-B, four-axle trucks were swapped out for C-C, six-axle trucks (all-powered). These were essentially the first "RSD-1" models.

New locomotives were later built for the original railroads (paid by the U.S. government) to replace those requisitioned, in April and May of 1943 (1946 for the Tennessee Coal, Iron & Railroad).

One of the Soo Line's rugged RS1s, #106 (built as Duluth, South Shore & Atlantic #106), is tied down at Burlington, Wisconsin in April, 1964. Rick Burn photo.

Production Rosters

Pre-War Production Board (WPB) Units

These RS1s were completed before the War Production Board (WPB) took control of manufacturing throughout the nation and imposed restrictions on new diesels produced. This went into effect on April 4, 1942.

Total Built = 13

Railroad	Road Number	Construction Number	Date Built	Date Rebuilt (Army)	U.S. War Department Number	Replacement Construction Number (RR)	Date Rebuilt For Railroads	New Road Number
Rock Island	748	69424	3/1941	11/1942	8005	70816	5/1943	742
Rock Island	749	69425	3/1941	12/1942	8006	70817	5/1943	743
Atlanta & St. Andrews Bay	901	69426	3/1941	1/1943	8010	70810	4/1943	904
Atlanta & St. Andrews Bay	902	69427	3/1941	1/1943	8011	70811	4/1943	904
Tennessee Coal, Iron & Railroad	600	69428	4/1941	12/1942	8008	75203	10/1946	602
Tennessee Coal, Iron & Railroad	601	69566	4/1941	1/1943	8009	75204	10/1946	603
Milwaukee Road	1678	69567	6/1941	11/1942	8002	70814	4/1943	1676
Milwaukee Road	1679	69568	6/1941	11/1942	8003	70815	4/1943	1677
Rock Island	746	69569	8/1941	12/1942	8007	70818	5/1943	744
Rock Island	747	69570	8/1941	11/1942	8004	70819	5/1943	745
Atlanta & St. Andrews Bay	903	69800	6/1942	1/1943	8012	70821	4/1943	906
New York, Susquehanna & Western	231	69992	6/1942	11/1942	8000	70812	4/1943	231
New York, Susquehanna & Western	233	69993	6/1942	11/1942	8001	70813	4/1943	233

The six-axle version came in either a C-C or A1A-A1A truck setup. The standard RS1 came in a B-B truck setup (four axles) and could produce 34,000 pounds of tractive effort with a top speed of 60 mph (although it rarely ever reached such speeds). It was quite short at just 54 feet, 11 inches and also featured a very low profile.

Overall, the model weighed just 120 tons and featured electrical and other components from both General Electric and Westinghouse. With the Rock Island's original request it was one of the initial railroads to receive the model when the first batches were completed in March of 1941, delivered to:

Tennessee Coal & Iron

Milwaukee Road

New York, Susquehanna & Western

Atlanta & St. Andrews Bay Railroad

Post World War II

Total Built = 340

Owner	Road Number(s)	Construction Number(s)	Completion Date
Akron, Canton & Youngstown	D-2	74323	10/1945
Alabama, Tennessee & Northern	101, 102	71435, 73096	11/1944, 12/1944
Alabama, Tennessee & Northern	103, 104	73326, 73327	3/1945
Alabama, Tennessee & Northern	105, 106	73758, 74321	6/1945, 10/1945
Alabama, Tennessee & Northern	107-109	75110-75112	5/1946 - 6/1946
Alabama, Tennessee & Northern	110, 111	75480, 75481	8/1947
Alaska Railroad	1000, 1001	71319, 71320	5/1944
Alton Railroad	50	74322	10/1945
Alton Railroad	51-53	74494-74496	11/1945
Alton Railroad	54-58	74677-74681	11/1945
Alton Railroad	59	74823	12/1945
Ann Arbor	20, 21	78374, 78375	11/1950
Santa Fe	2385-2387	75391-75393	6/1947 - 7/1947
Santa Fe	2388	75482	8/1947
Santa Fe	2394, 2395	78115, 77838	8/1950, 12/1949
Atlanta & St. Andrews Bay	904, 905	70810, 70811	4/1943
Atlanta & St. Andrews Bay	906	70821	4/1943
Atlanta & St. Andrews Bay	907, 908	70809, 70822	11/1943
Atlanta & St. Andrews Bay	909	72812	6/1944
Atlanta & St. Andrews Bay	910, 911	73332, 73333	4/1945
Atlanta & St. Andrews Bay	912, 913	75559, 77848	10/1947, 2/1950
Atlantic & East Carolina	500	79047	4/1951
Bamberger Railroad	570	70820	5/1943
Central Railroad of New Jersey	1200-1204	78095-78099	6/1950
Central Railroad of New Jersey	1205	79234	9/1951
Chesapeake & Ohio	5114, 5115	80851, 80852	9/1953
Chicago & Eastern Illinois	115-118	73328-73331	4/1945
Chicago & North Western	1066	79589	9/1953
Chicago & North Western	1067, 1068	79590, 79591	8/1953
Chicago & North Western	1069	80850	9/1953
Chicago & North Western	1080	72816	8/1944
Chicago & North Western	1081 (1st)	72921	9/1944
Chicago & Western Indiana	252, 253	76799, 76800	7/1949
Chicago & Western Indiana	254-257	77172-77175	10/1949 - 11/1949
Chicago & Western Indiana	258, 259	77836, 77837	12/1949
Chicago & Western Indiana	260-263	77849-77852	2/1950
Milwaukee Road	961-963	77469-77471	3/1950
Milwaukee Road	1676, 1677	70814, 70815	4/1943
Rock Island	735-739	71312-71316	1/1944 - 2/1944
Rock Island	740, 741	70823, 70824	11/1943
Rock Island	742-745	70816-70819	5/1943
Duluth, South Shore & Atlantic (Soo Line)	100, 101	73753, 73760	5/1945, 6/1945
Duluth, South Shore & Atlantic (Soo Line)	102	75215	12/1946
Duluth, South Shore & Atlantic (Soo Line)	103-105	75217-75219	1-2/1947
Duluth, South Shore & Atlantic (Soo Line)	106, 107	75389, 78376	5/1947, 1/1951
DuPont	105-108	79050-79053	6-7/1951
Gaylord Container	302, 303	75842, 75843	5/1948
GE-Atomic Energy Commission	39-3729, 39-3730	75844, 76206	6/1948
GE-Atomic Energy Commission	39-3731, 39-3732	76210, 76211	10/1948
Genesee & Wyoming	25, 30	79580, 81345	1/1952, 5/1955
Grand Trunk Western	1950, 1951	82355, 82356	11/1957
Great Northern	182, 183	72922, 72923	9/1944
Great Northern	184, 185	72924, 71433	11/1944, 10/1944
Gulf, Mobile & Ohio	1102	71438	11/1944
Gulf, Mobile & Ohio	1103, 1104	73094, 73095	12/1944
Gulf, Mobile & Ohio	1105-1107	73335-73337	4/1945
Gulf, Mobile & Ohio	1108, 1109	73573, 73574	5/1945
Gulf, Mobile & Ohio	1110	73752	5/1945
Gulf, Mobile & Ohio	1111, 1112	74910, 74911	1/1946, 4/1946
Gulf, Mobile & Ohio	1113	75216	1/1947
Gulf, Mobile & Ohio	1114, 1115	75220, 75221	2/1947
Gulf, Mobile & Ohio	1116, 1117	75223, 75224	3/1947
Gulf, Mobile & Ohio	1120	76219	12/1948
Gulf, Mobile & Ohio	1121, 1122	76624, 76625	1/1949
Gulf, Mobile & Ohio	1123-1125	76629-76631	3/1949 - 4/1949
Gulf, Mobile & Ohio	1126, 1127	76796, 76798	4/1949, 5/1949
Illinois Terminal	750-752	75839-75841	5/1948
Illinois Terminal	754	77855	3/1950
Illinois Terminal	755, 756	77069, 77070	3/1950
Kansas City Southern	1110-1113	70825-70828	11/1943 - 12/1943
Lake Erie, Franklin & Clarion	20, 21	76797, 78241	4/1949, 8/1950
Lake Superior & Ishpeming	1001-1003	79576-79578	11/1951 - 12/1951
Long Island Railroad	461, 462	76220, 76622	12/1948, 1/1949
Long Island Railroad	463-465	76626-76628	2/1949 - 3/1949
Long Island Railroad	466-469	77475-77478	4/1950
Midland Continental Railroad	401, 402	74912, 79579	4/1946, 12/1951
Minneapolis & St. Louis	244	71317	2/1944
Minneapolis & St. Louis	744, 944	71434, 71436	7/1944, 9/1944
Minneapolis & St. Louis	1044, 1144	73093, 79097	10/1944, 11/1944
Minneapolis & St. Louis	645, 745	73334, 73759	6/1945, 7/1945
Minneapolis & St. Louis	845, 945	74317, 74318	8/1945, 9/1945
Minneapolis &a St. Louis	146, 246	74821, 74822	1/1946, 2/1946
Minneapolis & St. Louis	346, 446	74824, 74909	3/1946, 4/1946
Minneapolis & St. Louis	546, 646	75113, 75114	5/1946, 6/1946
Minneapolis & St. Louis	746, 846	75115, 75116	7/1946, 8/1946
Minneapolis & St. Louis	946, 1046	75117, 75118	9/1946, 10/1946
Minneapolis & St. Louis	547	75390	5/1947
Minneapolis & St. Louis	948, 1048	76207, 76208	9/1948, 10/1948
Minneapolis & St. Louis	1148	76209	11/1948
Minneapolis & St. Louis	849, 949	77842, 77843	8/1949, 9/1949
Minneapolis & St. Louis	1049, 1149	77844, 77845	10/1949, 11/1949
Minneapolis & St. Louis	1249	77846	12/1959
Minneapolis & St. Louis	950, 1050	78243, 78244	9/1950, 10/1950
Minneapolis & St. Louis	1150, 1250	78245, 78373	11/1950, 12/1950
Minneapolis & St. Louis	751	79235	7/1951
Minneapolis & St. Louis	851, 951	79346, 79347	8/1951, 9/1951
Minneapolis, St. Paul & Sault Ste Marie (Soo Line)	350, 351	80853, 80854	12/1954
Minneapolis, St. Paul & Sault Ste Marie (Soo Line)	352, 353	80978, 80979	12/1954
New York Central	8100	75825	2/1948
New York Central	8101-8105	75680-75684	1/1948 - 2/1948
New York Central	8106-8108	75826-75828	2/1948 - 3/1948
New York Central	8109-8111	77986-77988	4/1950
New York Central	8112, 8113	78090, 78091	5/1950
New Haven	0660-0669	75829-75838	3/1948 - 4/1948
New Haven	0670, 0671	76212, 76213	11/1948
New York, Susquehanna & Western	230	71437	11/1944
New York, Susquehanna & Western	231, 233 (2nd)	70812, 70813	4/1943
New York, Susquehanna & Western	232-236 (Evens)	73098-73100	1/1945
New York, Susquehanna & Western	238, 240	73568, 73569	4/1945
New York, Susquehanna & Western	242, 244	73754, 73755	5/1945
New York, Susquehanna & Western	246-252 (Evens)	75555-75558	9/1947 - 10/1947
New York, Susquehanna & Western	254, 256	79584, 79585	6/1953
Northern Pacific	155	73761	6/1945
Northern Pacific	156	74316	10/1945
Northern Pacific	157, 158	73765, 73766	8/1945
Oregon Electric Railway	52-54	73570-73572	4/1945 - 5/1945
Oregon Electric Railway	55	73756	6/1945
Pennsylvania Railroad	5619, 5620	78106, 78107	6/1950
Pennsylvania Railroad	5621-5624	78110-78113	6/1950 - 7/1950
Pennsylvania Railroad	5625-5628	78100-78103	6/1950
Pennsylvania Railroad	5629	78114	8/1950
Pennsylvania Railroad	5630, 5631	78116, 78117	8/1950
Pennsylvania Railroad	5632-5636	78159-78163	8/1950
Pennsylvania Railroad	5637, 5638	78104, 78105	6/1950
Pennsylvania Railroad	5639, 5640	78108, 78109	6/1950
Pennsylvania Railroad	5906	76214	12/1948
Pennsylvania Railroad	8485, 8486	79582, 79583	5/1952
Pennsylvania Railroad	8857, 8858	78377, 79046	4/1951
Rutland Railway	400, 401	79349, 79350	10/1951
Rutland Railway	402-405	79572-79575	10/1951 - 11/1951
Spokane International	200-205	77166-77171	9/1949 - 10/1949
Spokane International	206-208	77839-77841	12/1949
Spokane International	209-211	79586-79588	7/1953 - 8/1953
Spokane, Portland & Seattle	50, 51	73757, 73762	6/1945, 7/1945
Tennessee Coal & Iron	602, 603	75203, 75204	10/1946
Tennessee Coal & Iron	604	75484	9/1947
U.S. Navy	6	72817	9/1944
Washington Terminal	40	71318	3/1944
Washington Terminal	41-43	72813-72815	6/1944 - 7/1944
Washington Terminal	44, 45	73763, 73764	7/1945, 8/1945
Washington Terminal	46, 47	74314, 74315	9/1945
Washington Terminal	48, 49	74319, 74320	10/1945
Washington Terminal	50-54	75560-75564	11/1947 - 12/1947
Washington Terminal	55	75679	12/1947
Washington Terminal	56-59	76215-76218	12/1948
Washington Terminal	60-62	77472-77474	3/1950
Washington Terminal	63, 64	79048, 79049	5/1951
Wisconsin Central (Soo Line)	2360, 2361	77853, 77854	2/1950, 3/1950
Wisconsin Central (Soo Line)	2362	78242	8/1950
Wisconsin Central (Soo Line)	2363, 2364	79054, 79055	8/1951
Wisconsin Central (Soo Line)	2365-2367	79231-79233	9/1951
Wisconsin Central (Soo Line)	2368	79581	3/1952

Export

Total Built = 116

Owner	Road Number(s)	Construction Number(s)	Completion Date
Arabian-American Oil Company (Saudi Arabia)	A11x50, A11x51	75222, 75488	2/1947, 9/1947
Arabian-American Oil Company (Saudi Arabia)	1002	76623	1/1949
Arabian-American Oil Company (Saudi Arabia)	1003, 1004	77071, 77072	3/1950
Arabian-American Oil Company (Saudi Arabia)	1005	79348	10/1951
Central Railway of Brazil	3100-3119	71413-71432	4/1945 - 10/1945
Central Railway of Brazil	3120-3133	73703-73716	10/1945 - 1/1946
Central Railway of Brazil	3134, 3135	75924, 75925	7/1948
Central Railway of Brazil	3136, 3137	75930, 75931	8/1948, 9/1948
São Paulo Railway (Brazil)	504-507	75926-75929	8/1948
São Paulo Railway (Brazil)	508, 509	75932, 75933	9/1948
Estrada de Ferro Santos-Jundiaí (Brazil)	510, 511	81346, 82018	4/1956, 12/1956
Ferrocarriles Nacionales de México (Mexico)	5606, 5607	77847, 77073	2/1950, 3/1950
Ferrocarriles Nacionales de México (Mexico)	5608, 5609	77989, 77990	4/1950
Ferrocarriles Nacionales de México (Mexico)	5610-5618	78033-78041	4/1950 - 5/1950
Ferrocarriles Nacionales de México (Mexico)	5619 (1st)	78042	5/1950
Ferrocarriles Nacionales de México (Mexico)	5620, 5621 (1st)	78088, 78089	5/1950
Ferrocarriles Nacionales de México (Mexico)	5619-5621 (2nd) [MLW]	76430-76432	4/1954
Ferrocarriles Nacionales de México (Mexico)	5622-5624 (1st)	78092-78094	5/1950
Ferrocarriles Nacionales de México (Mexico)	5622-5624 (2nd)	81347-81349	10/1956
Ferrocarriles Nacionales de México (Mexico)	5625-5631	82011-82017	10/1956 - 11/1956
Ferrocarriles Nacionales de México (Mexico)	5632-5638	82019-82025	12/1956 - 1/1957
Ferrocarriles Nacionales de México (Mexico)	5639-5643	82343-82347	1/1957 - 2/1957
Ferrocarriles Nacionales de México (Mexico)	5644-5650	82348-82354	7/1957 - 8/1957
Ferrocarriles Nacionales de México (Mexico)	5651	82357	5/1958
Ferrocarriles Nacionales de México (Mexico)	5652-5656	82923-82927	12/1958
Ferrocarriles Nacionales de México (Mexico)	5657-5662	83619-83624	12/1959 - 1/1960
Ferrocarriles Nacionales de México (Mexico)	5663 (Final RS1 built)	83680	3/1960

Kansas City Southern RS1 #1113 carries out switching work in Kansas City, circa 1967. American-Rails.com collection.

Despite only modest sales numbers the RS1 could be found on railroads across the country from the Pennsylvania and New York Central to the Milwaukee Road and Northern Pacific.

While most RS1s were used in light branch line work some were also utilized in other applications, such as switching passenger cars at passenger terminals.

The later RS2 and RS3 sold thousands to several railroads and private industries, offering just the right blend of size and power. Unfortunately, later models could not replicate the same success and throughout the 1950s Alco lost ground to EMD.