The Baldwin S-12 was a 1,200-horsepower

Horsepower

Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...

 diesel-electric locomotive

Locomotive

A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...

 intended for use in yard

Classification yard

A classification yard or marshalling yard is a railroad yard found at some freight train stations, used to separate railroad cars on to one of several tracks. First the cars are taken to a track, sometimes called a lead or a drill...

 switching

Switcher

A switcher or shunter is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been...

. The Baldwin Locomotive Works

Baldwin Locomotive Works

The Baldwin Locomotive Works was an American builder of railroad locomotives. It was located in Philadelphia, Pennsylvania, originally, and later in nearby Eddystone, Pennsylvania. Although the company was very successful as a producer of steam locomotives, its transition to the production of...

 produced a total of 451 units between 1951 and 1956. Utilizing the powerful 6-cylinder 606A diesel engine

Diesel engine

A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

 prime mover

Prime mover (locomotive)

In engineering, a prime mover is an engine that converts fuel to useful work. In locomotives, the prime mover is thus the source of power for its propulsion. The term is generally used when discussing any locomotive powered by an internal combustion engine...

, S-12s were known for their "lugging" power, despite being temperamental.

At least six intact examples of the S-12 are known to survive today at railroad museums. SMS Lines operates S-12 #301 at the Penn Warner industrial park

Industrial park

An industrial park is an area zoned and planned for the purpose of industrial development...

 at Morrisville, PA. One unit that was converted from a Baldwin DS-4-4-1000

Baldwin DS-4-4-1000

The Baldwin DS-4-4-1000 were two models of four-axle diesel-electric switching locomotives built by the Baldwin Locomotive Works between 1946 and 1951. The first models was powered by an 8-cylinder normally aspirated prime mover, but from 1948, a change was made to the second model powered by a...

 is in service today on the Whitewater Valley Railroad

Whitewater Valley Railroad

The Whitewater Valley Railroad is a heritage railroad in Indiana.The railroad is dedicated to the preservation and presentation of a 1970s era of branch line railroading. It is now operated by vintage diesel switchers during most of the year. Steam operations occur on or around labor day each year...

.

Original buyers

Railroad	Quantity	Road number	Notes
Baldwin-Lima-Hamiton Baldwin Locomotive Works The Baldwin Locomotive Works was an American builder of railroad locomotives. It was located in Philadelphia, Pennsylvania, originally, and later in nearby Eddystone, Pennsylvania. Although the company was very successful as a producer of steam locomotives, its transition to the production of...  (demonstrators)	2	1200–1201	to Rock Island 758–759
Atlanta and West Point Rail Road Atlanta and West Point Rail Road The Atlanta and West Point Rail Road was a railroad in the U.S. state of Georgia, forming the east portion of the Atlanta-Selma West Point Route. The company was chartered in 1847 as the Atlanta and LaGrange Rail Road and renamed in 1857; construction was begun in 1849-50 and completed in May 1854...	1	678
Akron and Barberton Belt Railroad Akron and Barberton Belt Railroad The Akron and Barberton Belt Railroad was a switching railroad that was built to serve various industries around cities of Barberton and Akron in Ohio. The main purpose was to switch chemical cars for Pittsburgh Plate Glass, Babcox and Wilcox Companies as well as O.C. Barber's match works, all in...	2	27–27
American Smelting and Refining Company	2	1954–1955
Apache Railway	1	600
Armco Steel, Hamilton, Ohio Hamilton, Ohio Hamilton is a city in Butler County, southwestern Ohio, United States. The population was 62,447 at the 2010 census. It is the county seat of Butler County. The city is part of the Cincinnati metropolitan area....	1	706
Baltimore and Ohio Railroad Baltimore and Ohio Railroad The Baltimore and Ohio Railroad was one of the oldest railroads in the United States and the first common carrier railroad. It came into being mostly because the city of Baltimore wanted to compete with the newly constructed Erie Canal and another canal being proposed by Pennsylvania, which...	5	463–467	Renumbered 9274–9278
Calumet and Hecla Mining Company Calumet and Hecla Mining Company The Calumet and Hecla Mining Company was a major copper-mining company based in the Michigan Copper Country. In the 19th century, the company paid out more than $72 million in shareholder dividends, more than any other mining company in the United States during that period.-History:In 1864, Edwin J...	1	203
Central of Georgia Railway	4	311–314
Central Railroad of New Jersey Central Railroad of New Jersey The Central Railroad of New Jersey , commonly known as the Jersey Central Lines or CNJ, was a Class I railroad with origins in the 1830s, lasting until 1976 when it was absorbed into Conrail with the other bankrupt railroads of the Northeastern United States...	7	1053–1059
Chicago and North Western Railway Chicago and North Western Railway The Chicago and North Western Transportation Company was a Class I railroad in the Midwest United States. It was also known as the North Western. The railroad operated more than of track as of the turn of the 20th century, and over of track in seven states before retrenchment in the late 1970s...	16	1073–1076, 1106–1109, 1117–1121, 1126–1128
Chicago, Milwaukee, St. Paul and Pacific Railroad Chicago, Milwaukee, St. Paul and Pacific Railroad The Milwaukee Road, officially the Chicago, Milwaukee, St. Paul and Pacific Railroad , was a Class I railroad that operated in the Midwest and Northwest of the United States from 1847 until its merger into the Soo Line Railroad on January 1, 1986. The company went through several official names...  (“Milwaukee Road”)	21	1905–1925	Renumbered 900–914, 920–925 (not in order)
Copper Range Railroad Copper Range Railroad The Copper Range Railroad was a small railroad company that operated from 1899 to 1972 in the western Upper Peninsula of the state of Michigan, United States....	1	200
Erie Railroad Erie Railroad The Erie Railroad was a railroad that operated in New York State, New Jersey, Pennsylvania, Ohio, Indiana, and Illinois, originally connecting New York City with Lake Erie...	12	617–628
Erie Mining Company	4	400–403
Great Northern Railway Great Northern Railway (US) The Great Northern Railway , running from Saint Paul, Minnesota, to Seattle, Washington—more than 1,700 miles —was the creation of the 19th century railroad tycoon James J. Hill and was developed from the Saint Paul and Pacific Railroad...	5	24–28
Kansas City Southern Railway Kansas City Southern Railway The Kansas City Southern Railway , owned by Kansas City Southern Industries, is the smallest and second-oldest Class I railroad company still in operation. KCS was founded in 1887 and is currently operating in a region consisting of ten central U.S. states...	4	1160–1163
Lehigh Valley Railroad Lehigh Valley Railroad The Lehigh Valley Railroad was one of a number of railroads built in the northeastern United States primarily to haul anthracite coal.It was authorized April 21, 1846 in the U.S. state of Pennsylvania and incorporated September 20, 1847 as the Delaware, Lehigh, Schuylkill and Susquehanna Railroad...	14	230–243
Michigan Limestone	2	116–117
Missouri-Kansas-Texas Railroad Missouri-Kansas-Texas Railroad The Missouri–Kansas–Texas Railroad was incorporated May 23, 1870. In its earliest days the MKT was commonly referred to as "the K-T", which was its stock exchange symbol; this common designation soon evolved into "the Katy"....	15	1201–1210	Renumbered
Monongahela Railway Monongahela Railway The Monongahela Railway was a coal-hauling short line railroad in Pennsylvania and West Virginia in the United States. It was jointly controlled originally by the Pennsylvania Railroad, New York Central subsidiary Pittsburgh and Lake Erie Railroad, and the Baltimore and Ohio Railroad, with NYC...	27	400–426
Missouri Pacific Railroad Missouri Pacific Railroad The Missouri Pacific Railroad , also known as the MoPac, was one of the first railroads in the United States west of the Mississippi River. MoPac was a Class I railroad growing from dozens of predecessors and mergers, including the St. Louis, Iron Mountain and Southern Railway , Texas and Pacific...	20	9200–9219	Renumbered 1260–1279
Missouri Pacific (International-Great Northern Railroad International-Great Northern Railroad The International – Great Northern Railroad was a railroad that operated in the U.S. state of Texas. It was created on September 30, 1873, when International Railroad and Houston and Great Northern Railroad merged.... )	10	9220–9226, 9230–9232
Missouri Pacific (St. Louis, Brownsville and Mexico Railway St. Louis, Brownsville and Mexico Railway The St. Louis, Brownsville & Mexico Railway was a 200-mile railroad that operated from Brownsville, Texas to Gulf Coast Junction in Houston. It passed through small southeast Texas communities such as Robstown, Corpus Christi, Bay City, and Harlingen as well as the Rio Grande Valley.-History:Uriah... )	3	9227–9229
Missouri Pacific (Union Railway)	7	9233–9239
McCloud River Railroad	2	30–31	#31 built as 800 hp; convertible to 1,200 hp (but never converted)
New Orleans Public Belt Railroad New Orleans Public Belt Railroad The New Orleans Public Belt Railroad is a non-profit terminal switching railroad, owned by the City of New Orleans. It connects with six Class I railroads serving the city, and provides switching and haulage service....	2	61–62
New York Central Railroad New York Central Railroad The New York Central Railroad , known simply as the New York Central in its publicity, was a railroad operating in the Northeastern United States...	21	9308–9328
Oliver Iron Mining Company	1	933
Patapsco and Back Rivers Railroad	3	345–347
Pennsylvania Railroad Pennsylvania Railroad The Pennsylvania Railroad was an American Class I railroad, founded in 1846. Commonly referred to as the "Pennsy", the PRR was headquartered in Philadelphia, Pennsylvania....	87	8100–8104, 8732–8796, 8976–8993
Pennsylvania-Reading Seashore Lines Pennsylvania-Reading Seashore Lines Pennsylvania-Reading Seashore Lines was a railroad that operated in southern New Jersey in the 20th century. It was created as a joint venture of the Pennsylvania Railroad and the Reading Company .- History :...	11	6017–6021, 6028–6033
Rayonier, Inc.	2	201–202
Seaboard Air Line Railroad Seaboard Air Line Railroad The Seaboard Air Line Railroad , which styled itself "The Route of Courteous Service," was an American railroad whose corporate existence extended from April 14, 1900, until July 1, 1967, when it merged with the Atlantic Coast Line Railroad, its longtime rival, to form the Seaboard Coast Line...	10	1462–1465, 1476–1481	to Seaboard Coast Line Railroad Seaboard Coast Line Railroad The Seaboard Coast Line Railroad was a former Class I railroad company operating in the Southeastern United States beginning in 1967. Its passenger operations were taken over by Amtrak in 1971...  203–206, 217–222
Sierra Railroad Sierra Railroad The Sierra Railroad Company a privately owned common carrier which has a freight division which handles all track maintenance and freight operations for all branches owned by the Sierra Railroad Company...	2	40, 42
Southern Railway	10	2290–2299
Southern Pacific Company	56	1442–1513, 1539–1550
Southern Pacific (Texas and New Orleans Railroad Texas and New Orleans Railroad The Texas and New Orleans Railroad is a former railroad in Texas and Louisiana. At one point the company was the largest railroad in Texas, with of trackage in 1934, but by 1961 there were only remaining when it was merged with parent company Southern Pacific.... )	3	105–107
Tennessee Coal, Iron and Railroad Company Tennessee Coal, Iron and Railroad Company The Tennessee Coal, Iron and Railroad Company , also known as TCI and the Tennessee Company, was a major American steel manufacturer with interests in coal and iron ore mining and railroad operations. Originally based entirely within Tennessee, it relocated most of its business to Alabama in the...	8	1200–1207
Tennessee Valley Authority Tennessee Valley Authority The Tennessee Valley Authority is a federally owned corporation in the United States created by congressional charter in May 1933 to provide navigation, flood control, electricity generation, fertilizer manufacturing, and economic development in the Tennessee Valley, a region particularly affected...	4	1–3, 200
Terminal Railroad Association of St. Louis Terminal Railroad Association of St. Louis The Terminal Railroad Association of St. Louis is a terminal railroad owned by railroads in St. Louis, Missouri which handles traffic through its metropolitan area.-Components:It was founded in 1889 in a deal orchestrated by Jay Gould by:...	4	1250–1253
United States Air Force United States Air Force The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...	2	1841–1842
United States Army United States Army The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...	1	65-11391
United States Navy United States Navy The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...	13	65-00292–65-00294, 65-365–65-00374
U.S. Steel U.S. Steel The United States Steel Corporation , more commonly known as U.S. Steel, is an integrated steel producer with major production operations in the United States, Canada, and Central Europe. The company is the world's tenth largest steel producer ranked by sales... , Geneva Steel Geneva Steel Geneva Steel was a steel mill located in Vineyard, Utah, founded during World War II to enhance national steel output. It operated from December 1944 to November 2001...  Works	3	33–35
U.S. Steel, Homestead Steel Works Homestead Steel Works Homestead Steel Works was a large steel works located on the Monongahela River at Homestead, Pennsylvania in the United States. It developed in the nineteenth century as an extensive plant served by tributary coal and iron fields, a railway long, and a line of lake steamships...	1	GE1
U.S. Steel, Morrisville, Pennsylvania Morrisville, Pennsylvania Morrisville is the name of some places in the U.S. state of Pennsylvania:*Morrisville, Bucks County, Pennsylvania *Morrisville, Greene County, Pennsylvania...  Works	9	GE2–GE8, GE17–GE18
Wabash Railroad Wabash Railroad The Wabash Railroad was a Class I railroad that operated in the mid-central United States. It served a large area, including trackage in the states of Ohio, Indiana, Illinois, Iowa, Michigan, Missouri and Ontario. Its primary connections included Chicago, Illinois, Kansas City, Missouri, Detroit,...	5	305–309
Total	451

External links

• Baldwin S-12
• Preserved Baldwin and Lima Locomotives