The Alco RSD-15 is a

diesel-electric locomotive A diesel locomotive is a type of railway locomotive in which the prime mover (locomotive), prime mover is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is conv ...

built by the

American Locomotive Company The American Locomotive Company (often shortened to ALCO, ALCo or Alco) was an American manufacturer of locomotives, diesel generators, steel, and tanks that operated from 1901 to 1969. The company was formed by the merger of seven smaller locomo ...

(ALCO) of

Schenectady, New York Schenectady () is a city in Schenectady County, New York, United States, of which it is the county seat. As of the 2020 census, the city's population of 67,047 made it the state's ninth-largest city by population. The city is in eastern New Y ...

between August 1956 and June 1960, during which time 75 locomotives were produced. The RSD-15 was powered by an

Alco 251 The Alco 251 is a 4-stroke diesel engine that was developed by the American Locomotive Company to replace its 244 and 539 engines. The 251 was developed to be used in diesel locomotives, as a marine power plant in ships, and as a stationary pow ...

16-cylinder four-cycle V-type

prime mover Prime mover may refer to: Philosophy *Unmoved mover, a concept in Aristotle's writings Engineering * Prime mover (engine), motor, a machine that converts various other forms of energy (chemical, electrical, fluid pressure/flow, etc) into energy o ...

rated at ; it superseded the almost identical

Alco 244 The ALCO 244 was a diesel prime mover built by the American Locomotive Company (ALCO). An evolution of the earlier 241 diesel engine, it powered ALCO's first generation of production road locomotives. The 244 engine was developed to create an engine ...

-engined RSD-7, and was catalogued alongside the similar but smaller RSD-12, powered by a 12-cylinder

251 __NOTOC__ Year 251 ( CCLI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Traianus and Etruscus (or, less frequently, year 1004 ' ...

-model V-type diesel engine. The locomotive rode on a pair of three-axle ''Trimount''

trucks A truck or lorry is a motor vehicle designed to transport cargo, carry specialized payloads, or perform other utilitarian work. Trucks vary greatly in size, power, and configuration, but the vast majority feature body-on-frame construction ...

with all axles powered by General Electric model 752 traction motors. These trucks have an asymmetrical axle spacing because of the positioning of the traction motors. The six-motor design allowed higher tractive effort at lower speeds than an otherwise similar four-motor design. The RSD-15 could be ordered with either a high or low

short hood Short may refer to: Places * Short (crater), a lunar impact crater on the near side of the Moon * Short, Mississippi, an unincorporated community * Short, Oklahoma, a census-designated place People * Short (surname) * List of people known as t ...

;

railfan A railfan, rail buff or train buff (American English), railway enthusiast, railway buff or trainspotter (Australian/British English), or ferroequinologist is a person who is recreationally interested in trains and rail transport systems. Rail ...

s dubbed the low short hood version "Alligators", due to their unusually long low noses.

RSD-17

A single example of the very similar model RSD-17 was built by the

Montreal Locomotive Works Montreal Locomotive Works (MLW) was a Canadian railway locomotive manufacturer which existed under several names from 1883 to 1985, producing both steam and diesel locomotives. For a number of years it was a subsidiary of the American Locomotive ...

in 1957. After demonstrating on the

Canadian Pacific The Canadian Pacific Railway (french: Chemin de fer Canadien Pacifique) , also known simply as CPR or Canadian Pacific and formerly as CP Rail (1968–1996), is a Canadian Class I railway incorporated in 1881. The railway is owned by Canadi ...

''(as #7007)'', the

Canadian National The Canadian National Railway Company (french: Compagnie des chemins de fer nationaux du Canada) is a Canadian Class I railroad, Class I freight railway headquartered in Montreal, Quebec, which serves Canada and the Midwestern United States, M ...

''(as #3899)'', and the

Pacific Great Eastern BC Rail is a railway in the Canadian province of British Columbia. Chartered as a private company in 1912 as the Pacific Great Eastern Railway (PGE), it was acquired by the provincial government in 1918. In 1972 it was renamed to the Britis ...

''(as #624)'', the locomotive was purchased by the Canadian Pacific ''(as #8921)''. Nicknamed "The Empress of Agincourt", by Pete Fairfull, who was its primary operator for many years, ''(for its common presence around Toronto's Agincourt yard)'', the locomotive served the railway until 1995, when truck problems forced its retirement.

Original owners

Surviving examples

Six RSD-15s survive in preservation; all are ex-Santa Fe units. Only two are in operating condition; the

Austin and Texas Central Austin is the capital city of the U.S. state of Texas, as well as the seat and largest city of Travis County, with portions extending into Hays and Williamson counties. Incorporated on December 27, 1839, it is the 11th-most-populous city ...

#442, originally ATSF 842, painted in a modified Southern Pacific "Black Widow" scheme, and

Green Bay and Western Railroad The Green Bay and Western Railroad served central Wisconsin for almost 100 years before it was absorbed into the Wisconsin Central in 1993. For much of its history the railroad was also known as the Green Bay Route. At the end of 1970 it operat ...

RSD-15 #2407 (originally ATSF 841) at the

Illinois Railway Museum The Illinois Railway Museum (IRM, reporting mark IRMX) is the largest railroad museum in the United States. It is located in the Chicago metropolitan area at 7000 Olson Road in Union, Illinois, northwest of downtown Chicago. Overview Histo ...

. Others that are preserved are Santa Fe 823, in second owner

Utah Railway Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its we ...

colors at the Utah Railroad Museum, the

California State Railroad Museum The California State Railroad Museum is a museum in the state park system of California, United States, interpreting the role of the "iron horse" in connecting California to the rest of the nation. It is located in Old Sacramento State Historic ...

Sacramento ) , image_map = Sacramento County California Incorporated and Unincorporated areas Sacramento Highlighted.svg , mapsize = 250x200px , map_caption = Location within Sacramento ...

has one (Santa Fe #9820) and the Arkansas Railroad Museum has Santa Fe #843. The RSD-17 demonstrator, Canadian Pacific 8921, is preserved at the

Elgin County Railway Museum The Elgin County Railway Museum is a rail transport museum in St. Thomas, Ontario. The museum and most of the collections are housed in the former Michigan Central Railroad locomotive shops. Built in 1913, the shops were part of more extensi ...

, St. Thomas, Ontario,

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

Models

The RSD-15 has been produced in

N scale N scale is a popular model railway scale. Depending upon the manufacturer (or country), the scale ranges from 1:148 to 1:160. In all cases, the ''gauge'' (the distance between the rails) is . The term N ''gauge'' refers to the track dimensions, ...

by Mehano of Yugoslavia and Broadway Limited of the United States. The RSD-15 has been produced in

HO scale HO or H0 is a rail transport modelling scale using a 1:87 scale (3.5 mm to 1 foot). It is the most popular scale of model railway in the world. The rails are spaced apart for modelling standard gauge tracks and trains in HO.NMRA"M ...

Broadway Limited Imports Broadway Limited Imports, LLC (BLI) designs and manufactures limited-run HO scale and N scale model railroad locomotives and rolling stock. BLI products, produced in extremely limited quantities, are equipped with Digital Command Control decoders a ...

and handmade brass. Alco Models (DL600b) high and Low hoods. Also (Overland Models). The RSD-15 has been produced in

O scale O scale (or O gauge) is a scale commonly used for toy trains and rail transport modelling. Introduced by German toy manufacturer Märklin around 1900, by the 1930s three-rail alternating current O gauge was the most common model railroad scal ...

by Atlas O in their Trainman line. The RSD-17 has not been mass-produced in any scale; however, in 2008

did produce a limited run of the high-hood CP 8921 in

References

External links