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Baldwin "S-12" Locomotives: Specs, Roster, Data Sheet

Last revised: December 31, 2024

By: Adam Burns

The S-12 was an upgraded version of its predecessor, the S-8, although both models were cataloged at the same time.

Similar in size and mechanics, save for increased horsepower, this final switcher manufactured during the 1950s sold relatively well for Baldwin as numerous railroads and private industries purchased the model.

While the locomotive did have some complaints regarding reliability it was revered for its ability to out-pull nearly anything in its class (a Baldwin trademark thanks to their Westinghouse traction motors). 

The S-12 also saw the builder do away with the earlier complicated classification system and introducing one much simpler. Today, there are eight S-12's known to be preserved at museums while others are still hauling freight for short line carriers.  

Photos

72592903572367278246878390098.jpgPenn Central S-12 #8144 (ex-Pennsylvania #8784) is seen here in Charleston, West Virginia on the former New York Central in the fall of 1968. Fred Byerly photo. American-Rails.com collection.

Overview

Baldwin may have struggled as a diesel manufacturer but its switchers and road-switchers boasted good looks and clean lines, topped by a centered head-light on the long hood sporting decorative beveling. 

From a functionality standpoint they sat high and offered crews relatively good visibility on a modest frame.   The S-12 began production in 1951 and by that time was technically a product of the Baldwin-Lima-Hamilton Corporation (BLH).

BLH was formed through the merger of the Baldwin Locomotive Works and Lima-Hamilton in 1951 after the former came under the control of Westinghouse Electric Company, a long time supplier of internal components for Baldwin's diesels.

The two companies had collaborated on several electric locomotive projects over the years, dating all of the back to the 19th century.  Thanks to the S-12's increased horsepower it sold much better than its less powerful counterpart. 

29589023947126412657263893097.jpgMilwaukee Road S12 #912 (built as #1923) carries out switching chores at St. Paul Union Depot in April of 1968. Fred Byerly photo. American-Rails.com collection.

At 1,200 horsepower using Baldwin's latest prime mover, the 606A SC, railroads found the locomotive quite versatile in several applications from yard and industrial work to revenue service on secondary and branch lines. 

The locomotive came equipped with standard four axle (B-B) trucks and could produce a hefty 72,000 pounds of starting tractive effort (34,000 pounds continuous). 

Reception

When production had ended in August, 1956 the model had been sold to several railroads like the Chicago & North Western, Jersey Central, Southern Pacific, New York Central, Southern, and the ever-loyal Pennsylvania.

Additionally the military and industries purchased the locomotive including the Army, U.S. Steel, Armco Steel, American Smelting and Refining Company, Erie Mining, and others. In total, Baldwin sold 451 examples of the S-12.

Penn Central S12 #8337 (ex-PRR #8733) in Baltimore, Maryland; October 2, 1972. American-Rails.com collection.

The S-12 was certainly Baldwin's most popular switcher in terms of its horsepower rating and general reliability. This is a significant reason why the model continues to find use in short line service today, notably on short line SMS Lines which owns eight.

Data Sheet and Specifications

Entered Production9/8/1950 (Lehigh Valley #230)
Years Produced9/8/1950 - 8/6/1956
Baldwin ClassDS-4-4-1200/1 SC (S-12)
Engine606A, 6-Cylinder In-Line, Supercharged
Engine BuilderDe La Vergne
TurbochargerModel H-503 (Elliott Company)
Horsepower1200
RPM625
Carbody StylingBaldwin
Length (Between Coupler Pulling Faces)48'
Weight240,000 Lbs
Height (Top Of Rail To Top Of Cab)14'
Width10'
TrucksB-B
Truck TypeGSC Rigid Bolster, Drop-Side Equalizer
Truck Wheelbase8'
Wheel Size40"
Traction Motors362D (4), Westinghouse
Traction Generator480D, Westinghouse
Auxiliary GeneratorYG40D, Westinghouse
Gear Ratio16:76
Tractive Effort Rating33,600 Lbs at 8.3 MPH.
Top Speed45 MPH

Production Roster

Total Built = 451

Owner Road Number Baldwin Serial Number Construction Number Completion Date
Pennsylvania89761748571/12/1951
Pennsylvania89772748581/12/1951
Pennsylvania89783748591/15/1951
Pennsylvania89794748601/15/1951
Pennsylvania89805748611/18/1951
Pennsylvania89816748621/19/1951
Pennsylvania89827748632/20/1951
Pennsylvania89838748642/13/1951
Pennsylvania89849748652/13/1951
Pennsylvania898510748662/15/1951
Pennsylvania898611748672/16/1951
Pennsylvania898712748682/16/1951
Pennsylvania898813748693/6/1951
Pennsylvania898914748703/7/1951
Pennsylvania899015748713/9/1951
Pennsylvania899116748723/15/1951
Pennsylvania899217748733/28/1951
Pennsylvania899318748743/29/1951
Erie Railroad61719748752/2/1951
Erie Railroad61820748762/2/1951
Southern Pacific144221748771/23/1951
Southern Pacific144322748781/31/1951
Southern Pacific144423748791/26/1951
Southern Pacific144524748801/30/1951
Southern Pacific144625749701/30/1951
Southern Pacific144726749711/31/1951
Southern Pacific144827749721/31/1951
Southern Pacific144928749732/19/1951
Southern Pacific145029749742/20/1951
Southern Pacific145130749752/21/1951
Southern Pacific145231749762/22/1951
Southern Pacific145332749772/26/1951
Southern Pacific145433749782/26/1951
Southern Pacific145534749792/27/1951
Lehigh Valley230*35749529/8/1950
Lehigh Valley23136749539/14/1950
Lehigh Valley23237749549/14/1950
Lehigh Valley23338749559/14/1950
Lehigh Valley240397495610/25/1950
Lehigh Valley241407495710/27/1950
Lehigh Valley242417495810/27/1950
Lehigh Valley243427495910/31/1950
Lehigh Valley23443749608/15/1950
Lehigh Valley23544749618/25/1950
Lehigh Valley23645749629/25/1950
Lehigh Valley237467496310/23/1950
Lehigh Valley238477496410/23/1950
Lehigh Valley239487496510/25/1950
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1905497500711/22/1950
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1906507500811/28/1950
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1907517500911/28/1950
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1908527501011/29/1950
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1909537501111/30/1950
Tennessee Coal, Iron & Railroad1200547501210/13/1950
Tennessee Coal, Iron & Railroad1201557501310/17/1950
Tennessee Coal, Iron & Railroad1202567501410/17/1950
Tennessee Coal, Iron & Railroad1203577501510/18/1950
Tennessee Coal, Iron & Railroad1204587501610/25/1950
Southern Pacific145659750173/16/1951
Southern Pacific145760750183/21/1951
Southern Pacific145861750194/2/1951
Southern Pacific145962750204/18/1951
Southern Pacific146063750214/20/1951
Southern Pacific146164750224/24/1951
Southern Pacific146265750234/26/1951
Southern Pacific146366750244/26/1951
Central Railroad Of New Jersey105367750256/25/1951
Central Railroad Of New Jersey105468750266/25/1951
Central Railroad Of New Jersey105569750276/28/1951
Akron & Barberton Belt2770750285/1/1951
Tennessee Coal, Iron & Railroad120571750295/10/1951
Tennessee Coal, Iron & Railroad120672750305/15/1951
Tennessee Coal, Iron & Railroad120773750315/15/1951
Sharon Steel Corporation174750325/21/1951
Missouri Pacific920075750335/16/1951
Missouri Pacific920176750345/21/1951
Missouri Pacific920277750355/22/1951
Missouri Pacific920378750365/22/1951
Missouri Pacific920479750375/28/1951
Missouri Pacific920580750385/28/1951
Missouri Pacific920681750395/28/1951
Missouri Pacific920782750405/29/1951
Missouri Pacific920883750416/5/1951
Missouri Pacific920984750426/7/1951
Missouri Pacific921085750436/8/1951
Missouri Pacific921186750446/8/1951
Missouri Pacific921287750456/14/1951
Missouri Pacific921388750466/18/1951
Missouri Pacific921489750476/21/1951
Missouri Pacific921590750486/20/1951
Missouri Pacific921691750496/21/1951
Missouri Pacific921792750507/6/1951
Missouri Pacific921893750519/7/1951
Missouri Pacific921994750529/7/1951
Oliver Iron Mining Company93395750536/30/1951
Kansas City Southern116096750544/10/1951
Kansas City Southern116197750554/10/1951
Kansas City Southern116298750564/12/1951
Kansas City Southern116399750574/13/1951
Central Railroad Of New Jersey1056100750586/29/1951
Central Railroad Of New Jersey1057101750596/30/1951
Central Railroad Of New Jersey1058102750606/29/1951
Central Railroad Of New Jersey1059103750616/30/1951
Wabash305104750624/30/1951
Wabash306105750634/30/1951
Chicago & North Western1073106750647/12/1951
Chicago & North Western1074107750657/12/1951
Chicago & North Western1075108750667/16/1951
Chicago & North Western1076109750677/17/1951
Copper Range Railroad200110750687/28/1951
Sharon Steel Corporation10111751407/23/1951
Calumet & Hecla203112751419/4/1951
Seaboard Air Line1462113751421/28/1952
Seaboard Air Line1463114751431/28/1952
Seaboard Air Line1464115751441/31/1952
Seaboard Air Line1465116751451/31/1952
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19101177514611/14/1951
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19111187514711/14/1951
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19121197514811/24/1951
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19131207514911/21/1951
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19141217515011/21/1951
Patapsco & Back Rivers345122752349/7/1951
Patapsco & Back Rivers346123752359/10/1951
Patapsco & Back Rivers347124752369/10/1951
New York Central93081257527510/24/1951
New York Central93091267527610/24/1951
New York Central93101277527710/25/1951
Chicago, Milwaukee, St. Paul & Pacific19151287527811/10/1951
Chicago, Milwaukee, St. Paul & Pacific19161297527911/10/1951
Atlanta & West Point678130752807/19/1951
U.S. Steel-Homestead Works (PA)GE1131752817/3/1951
U.S. Steel-Fairless Works (Morrisville, PA)GE2132752827/6/1951
U.S. Steel-Fairless Works (Morrisville, PA)GE3133752838/22/1951
U.S. Steel-Fairless Works (Morrisville, PA)GE4134752849/21/1951
U.S. Steel-Fairless Works (Morrisville, PA)GE5135752859/17/1951
U.S. Steel-Fairless Works (Morrisville, PA)GE6136752863/7/1952
U.S. Steel-Fairless Works (Morrisville, PA)GE7137752873/7/1952
U.S. Steel-Fairless Works (Morrisville, PA)GE8138752883/7/1952
U.S. Navy65-002921397528912/21/1951
U.S. Navy65-002931407529012/21/1951
U.S. Navy65-002941417529112/21/1951
Pennsylvania87771427529212/28/1951
Pennsylvania87781437529312/31/1951
Pennsylvania87791447529412/31/1951
Pennsylvania8780145752951/7/1952
Pennsylvania8781146752961/10/1952
Pennsylvania8782147752971/28/1952
Pennsylvania8783148752981/23/1952
Pennsylvania8784149752991/23/1952
Pennsylvania8785150753001/23/1952
Pennsylvania8786151753011/28/1952
Pennsylvania8787152753021/23/1952
Pennsylvania8788153753032/14/1952
Pennsylvania8789154753042/15/1952
Pennsylvania8790155753052/18/1952
Pennsylvania8791156753062/19/1952
Pennsylvania8792157753072/25/1952
Pennsylvania8793158753082/21/1952
Pennsylvania8794159753092/25/1952
Pennsylvania8795160753102/29/1952
Pennsylvania8796161753112/27/1952
Tennessee Valley Authority200162753121/30/1952
St. Louis, Brownsville & Mexico (MP)9227163753134/18/1952
St. Louis, Brownsville & Mexico (MP)9228165753144/18/1952
Akron & Barberton Belt28166753167/18/1952
Missouri-Kansas-Texas (Katy)1201167755049/29/1951
Missouri-Kansas-Texas (Katy)12021687550510/2/1951
Missouri-Kansas-Texas (Katy)12031697550610/3/1951
Missouri-Kansas-Texas (Katy)12041707550710/4/1951
Missouri-Kansas-Texas (Katy)12051717550810/11/1951
Missouri-Kansas-Texas (Katy)12061727550910/17/1951
Missouri-Kansas-Texas (Katy)12071737551012/7/1951
Missouri-Kansas-Texas (Katy)12081747551112/10/1951
Missouri-Kansas-Texas (Katy)12091757551212/22/1951
Missouri-Kansas-Texas (Katy)12101767551312/26/1951
International-Great Northern (MP)9230177755284/22/1952
International-Great Northern (MP)9231178755294/24/1952
International-Great Northern (MP)9232179755304/25/1952
International-Great Northern (MP)9220180755313/24/1952
International-Great Northern (MP)9221181755323/24/1952
International-Great Northern (MP)9222182755333/26/1952
International-Great Northern (MP)9223183755343/27/1952
International-Great Northern (MP)9224184755354/10/1952
International-Great Northern (MP)9225185755364/10/1952
International-Great Northern (MP)9226186755374/11/1952
U.S. Steel-Fairless Works (Morrisville, PA)GE17187755422/13/1952
U.S. Steel-Fairless Works (Morrisville, PA)GE18188755432/14/1952
American Smelting & Refining Company1954189755444/3/1952
American Smelting & Refining Company1955190755454/3/1952
New York Central9311191755466/23/1952
New York Central9312192755476/23/1952
New York Central9313193755486/25/1952
New York Central9314194755496/25/1952
New York Central9315195755506/25/1952
New York Central9316196755516/27/1952
New York Central9317197755526/27/1952
New York Central9318198755536/27/1952
New York Central9319199755546/28/1952
New York Central9320200755556/30/1952
New York Central9321201755566/28/1952
New York Central9322202755577/7/1952
New York Central9323203755587/8/1952
New York Central9324204755597/9/1952
New York Central9325205755607/9/1952
New York Central9326206755617/10/1952
New York Central9327207755627/11/1952
New York Central9328208755637/15/1952
Tennessee Valley Authority1209756017/17/1952
Tennessee Valley Authority2210756027/17/1952
Southern2290211756037/18/1952
Southern2291212756047/22/1952
Southern2292213756057/23/1952
Southern2293214756067/23/1952
Southern2294215756077/24/1952
Southern2295216756087/24/1952
Southern2296217756097/25/1952
Southern2297218756107/25/1952
Southern2298219756117/26/1952
Southern2299220756127/30/1952
Texas & New Orleans (SP)105221756132/8/1952
Texas & New Orleans (SP)106222756142/8/1952
Texas & New Orleans (SP)107223756152/8/1952
Apache Railway600224756166/25/1952
Minneapolis, St. Paul & Sault Ste. Marie313225756173/31/1952
Minneapolis, St. Paul & Sault Ste. Marie314226756183/31/1952
Pennsylvania8753227756198/26/1952
Pennsylvania8754228756208/27/1952
Pennsylvania8755229756218/28/1952
Pennsylvania8756230756228/28/1952
Pennsylvania8757231756239/2/1952
Pennsylvania8758232756248/29/1952
Pennsylvania8759233756259/3/1952
Pennsylvania8760234756269/4/1952
Pennsylvania8761235756279/5/1952
Pennsylvania8762236756289/5/1952
Pennsylvania8763237756299/8/1952
Pennsylvania8764238756309/8/1952
Pennsylvania8732239756319/24/1952
Pennsylvania8733240756329/25/1952
Pennsylvania8734241756339/25/1952
Pennsylvania8735242756349/26/1952
Pennsylvania8736243756359/30/1952
Pennsylvania8737244756369/30/1952
Pennsylvania8738245756379/30/1952
Pennsylvania8739246756389/30/1952
Pennsylvania87402477563910/7/1952
Pennsylvania87412487564010/7/1952
Pennsylvania87422497564110/9/1952
Pennsylvania87432507564210/9/1952
Pennsylvania87442517564310/13/1952
Pennsylvania87452527564410/13/1952
Pennsylvania87462537564510/14/1952
Pennsylvania87472547564610/14/1952
Pennsylvania87482557564710/18/1952
Pennsylvania87492567564810/16/1952
Pennsylvania87502577564910/17/1952
Pennsylvania87512587565010/21/1952
Pennsylvania87522597565110/21/1952
Pennsylvania87652607565210/28/1952
Pennsylvania87662617565310/23/1952
Pennsylvania87672627565410/23/1952
Pennsylvania87682637565510/24/1952
Pennsylvania87732647565612/31/1952
Pennsylvania87742657565712/22/1952
Pennsylvania87752667565812/23/1952
Pennsylvania87692677565912/19/1952
Pennsylvania87702687566012/22/1952
Pennsylvania87712697566112/24/1952
Pennsylvania87722707566212/24/1952
Erie Railroad619271756724/29/1952
Erie Railroad620272756734/29/1952
Erie Railroad621273756745/2/1952
Erie Railroad622274756755/2/1952
Erie Railroad623275756765/8/1952
Erie Railroad624276756775/8/1952
Erie Railroad625277756785/15/1952
Erie Railroad626278756795/15/1952
Erie Railroad627279756805/19/1952
Erie Railroad628280756815/21/1952
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19172817570110/31/1952
Terminal Railroad Association Of St. Louis1250282756888/22/1952
Terminal Railroad Association Of St. Louis1251283756898/22/1952
Terminal Railroad Association Of St. Louis1252284756908/25/1952
Terminal Railroad Association Of St. Louis1253285756918/25/1952
Chicago & North Western1106286751949/19/1952
Chicago & North Western1107287751959/19/1952
Chicago & North Western1108288751969/22/1952
Chicago & North Western1109289756829/22/1952
Central Procurement AgencyUSAF18412907570312/1/1952
Central Procurement AgencyUSAF18422917570412/1/1952
Central Procurement AgencyUSN65-003652927570511/29/1952
Central Procurement AgencyUSN65-003662937570611/29/1952
Central Procurement AgencyUSN65-003672947570711/29/1952
Central Procurement AgencyUSN65-003682957570811/29/1952
Central Procurement AgencyUSN65-003692967570911/29/1952
Central Procurement AgencyUSN65-003702977571012/4/1952
Central Procurement AgencyUSN65-003712987571112/5/1952
Central Procurement AgencyUSN65-003722997571212/5/1952
Central Procurement AgencyUSN65-003733007571312/10/1952
Central Procurement AgencyUSN65-003743017571412/10/1952
Missouri-Kansas-Texas (Katy)1211302751836/10/1952
Missouri-Kansas-Texas (Katy)1212303751846/10/1952
Missouri-Kansas-Texas (Katy)1213304751916/11/1952
Missouri-Kansas-Texas (Katy)1214305751926/12/1952
Missouri-Kansas-Texas (Katy)1215306751936/16/1952
McCloud River Railroad303077591210/6/1953
Southern Pacific14923087577410/31/1952
Southern Pacific14933097577510/31/1952
Southern Pacific14943107577610/31/1952
Southern Pacific14953117577711/6/1952
Southern Pacific14963127577811/7/1952
Southern Pacific14973137577911/10/1952
Southern Pacific14983147578011/11/1952
Southern Pacific14993157578111/11/1952
Southern Pacific15003167578212/11/1952
Southern Pacific15013177578312/16/1952
Southern Pacific15023187578412/15/1952
Southern Pacific15033197578512/15/1952
Southern Pacific15043207578612/18/1952
Southern Pacific15053217578712/18/1952
Southern Pacific15063227578812/20/1952
Southern Pacific1507323757892/17/1953
Southern Pacific1508324757902/17/1953
Southern Pacific1509325757912/18/1953
Southern Pacific1510326757922/19/1953
Southern Pacific1511327757932/19/1953
Southern Pacific1512328757942/20/1953
Southern Pacific1513329757952/26/1953
Seaboard Air Line1476330757591/21/1953
Seaboard Air Line1477331757601/23/1953
Seaboard Air Line1478332757611/27/1953
Seaboard Air Line1479333757621/27/1953
Seaboard Air Line1480334757631/28/1953
Seaboard Air Line1481335757641/28/1953
Central Procurement AgencyUSA65-11391336757962/13/1953
Monongahela Railway4003377579711/19/1952
Monongahela Railway4013387579811/18/1952
Monongahela Railway4023397579911/18/1952
Monongahela Railway4033407580011/19/1952
Monongahela Railway4043417580111/21/1952
Monongahela Railway4053427580211/21/1952
Monongahela Railway4063437580311/25/1952
Central Of Georgia311344758143/25/1953
Central Of Georgia312345758153/25/1953
Central Of Georgia313346758164/14/1953
Central Of Georgia314347758174/14/1953
Central Of Georgia314347758174/14/1953
Great Northern24348758182/11/1953
Great Northern25349758192/11/1953
Great Northern26350758202/11/1953
Great Northern27351758212/11/1953
Great Northern28352758222/11/1953
Wabash307353758232/23/1953
Wabash308354758242/23/1953
Wabash309355758252/25/1953
Pennsylvania-Reading Seashore Lines6017356759306/4/1953
Pennsylvania-Reading Seashore Lines6018357759316/4/1953
Pennsylvania-Reading Seashore Lines6019358759326/4/1953
Pennsylvania-Reading Seashore Lines6020359759336/4/1953
Baldwin-Lima-Hamilton1200360759357/24/1953
Baldwin-Lima-Hamilton1201361759367/24/1953
Union Railway (MP)9233362758274/23/1953
Union Railway (MP)9234363758284/23/1953
Union Railway (MP)9235364758294/23/1953
Union Railway (MP)9236365758304/24/1953
Union Railway (MP)9237366758315/5/1953
Union Railway (MP)9238367758325/7/1953
Union Railway (MP)9239368758335/13/1953
Monongahela Railway407369758385/22/1953
Monongahela Railway408370758395/22/1953
Monongahela Railway409371758406/23/1953
Monongahela Railway410372758416/23/1953
Monongahela Railway411373758427/3/1953
Monongahela Railway412374758427/3/1953
Monongahela Railway413375758437/3/1953
Monongahela Railway414376758447/9/1953
Monongahela Railway415377758457/9/1953
Monongahela Railway416378758467/14/1953
Monongahela Railway417379758477/14/1953
Monongahela Railway418380758487/14/1953
Chicago & North Western1117381753946/12/1953
Chicago & North Western1118382753956/18/1953
Chicago & North Western1119383753966/12/1953
Chicago & North Western1120384753976/12/1953
Chicago & North Western1121385753986/23/1953
McCloud River Railroad313867591310/30/1953
Southern Pacific1539387759149/24/1953
Southern Pacific1540388759159/24/1953
Southern Pacific1541389759169/29/1953
Southern Pacific1542390759179/29/1953
Southern Pacific1543391759189/30/1953
Southern Pacific1544392759199/30/1953
Southern Pacific1545393759209/30/1953
Southern Pacific1546394759219/30/1953
Southern Pacific15473957592210/16/1953
Southern Pacific15483967592310/22/1953
Southern Pacific15493977592410/28/1953
Southern Pacific15503987592510/31/1953
Pennsylvania-Reading Seashore Lines6021399759347/29/1953
Tennessee Valley Authority3400759377/14/1954
Pennsylvania8100401759452/3/1954
Pennsylvania8101402759462/3/1954
Pennsylvania8102403759472/3/1954
Pennsylvania8103404759482/8/1954
Pennsylvania8104405759492/12/1954
Michigan Limestone1164067595911/27/1953
Michigan Limestone1174077596012/1/1953
Baltimore & Ohio4634087596111/11/1953
Baltimore & Ohio4644097596211/11/1953
Baltimore & Ohio4654107596311/16/1953
Baltimore & Ohio4664117596411/18/1953
Baltimore & Ohio4674127596511/20/1953
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19184137596712/28/1953
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19194147596812/28/1953
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19204157596912/28/1953
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)19214167597012/28/1953
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1922417759711/22/1954
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1923418759721/22/1954
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1924419759731/28/1954
Chicago, Milwaukee, St. Paul & Pacific (Milwaukee Road)1925420759741/29/1954
Monongahela Railway419421760103/21/1954
Monongahela Railway420422760113/21/1954
Monongahela Railway421423760123/21/1954
Monongahela Railway422424760133/21/1954
Monongahela Railway423425760146/23/1954
Monongahela Railway424426760156/23/1954
Monongahela Railway425427760166/23/1954
Sierra Railroad40431760922/16/1955
Sierra Railroad42432760932/17/1955
Armco Steel-Hamilton Plant (Ohio)706433760912/28/1955
New Orleans Public Belt614347612012/27/1955
New Orleans Public Belt624357612112/27/1955
Chicago & North Western1126436760257/27/1954
Chicago & North Western1127437760267/30/1954
Chicago & North Western1128438760277/30/1954
Erie Mining Company4004397611610/17/1955
Erie Mining Company4014407611710/17/1955
Erie Mining Company4024417611810/17/1955
Pennsylvania-Reading Seashore Lines6028442761264/5/1956
Pennsylvania-Reading Seashore Lines6029443761274/5/1956
Pennsylvania-Reading Seashore Lines6030444761284/17/1956
Pennsylvania-Reading Seashore Lines6031445761294/17/1956
Pennsylvania-Reading Seashore Lines6032446761304/30/1956
Pennsylvania-Reading Seashore Lines6033447761314/30/1956
Erie Mining Company4034487612510/30/1956
Rayonier Inc.201449761367/17/1956
Rayonier Inc.202450761377/17/1956
U.S. Steel-Geneva Works(Vineyard, UT)33451761388/6/1956
U.S. Steel-Geneva Works(Vineyard, UT)34452761398/6/1956
U.S. Steel-Geneva Works(Vineyard, UT)35453761408/6/1956

* First S-12 produced.

81328742527358269766.jpgU.S. Air Force S-12 #1864 at Hill Air Force Base (Utah) in February, 1970. This unit was built as U.S. Navy #65-00374, one of three the branch owned. Rick Burn photo.

Preservation

The heritage of these locomotives includes:

  • Michigan Limestone #116

  • Tennessee Valley Authority #200

  • U.S. Navy #65-00372

  • Demonstrator #1200

  • Southern Pacific #1547

  • Erie Mining #7241

  • Monongahela Railway #425

  •  Great Northern #27. 

While four of these locomotives are operational, four are also used as a parts source.  Additionally, seven others can be found at museums:

  • Patapsco & Back Rivers #345-#346

  • Erie Mining #403

  • New York Central #9313

  • Southern Pacific #1550

  • Texas & New Orleans (SP) #121

  • Oliver Iron Mining #933
02984172471242578236892396889767.jpgKansas City Southern S-12 #1160 lays over in Kansas City, circa 1965. Photographer unknown. American-Rails.com collection.

Sources

  • Foster, Gerald. A Field Guide To Trains. New York: Houghton Mifflin, 1996.
  • Kirkland, John F. Diesel Builders, The:  Volume Three, Baldwin Locomotive Works. Pasadena: Interurban Press, 1994.
  • Pinkepank, Jerry A. Diesel Spotter's Guide.  Milwaukee: Kalmbach Publishing Company, 1967.
  • Solomon, Brian.  Baldwin Locomotives.  Minneapolis:  Voyageur Press, 2009.

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