Baldwin S-12

The BLH S12 was a 1,200-horsepower (890 kW) diesel-electric locomotive intended for use in yard switching. Utilizing a turbocharged 6-cylinder version of the powerful 606A diesel prime mover, S12s were known for their "lugging" power, despite being temperamental. Like most BLH switchers, the S12 had AAR Type-A switcher trucks in a B-B wheel arrangement. 451 units were built between 1951 and 1956, when BLH left the locomotive market.
==Previous models==
Baldwin made a number of switchers with similar dimensions and body styles. The first body style, used in VO models, had a slightly pointed nose with a round radiator opening. The second and third body style, almost indistinguishable and used interchangeably, had a flat nose and rectangular radiator opening. Various exhaust stacks were used, and are not an effective spotting feature, except that turbocharged models always had one large stack offset to the side.
The VO-660 was built between April 1939 and May 1946. It was powered by a naturally aspirated six cylinder engine rated at 600-horsepower (450 kW). 142 were built. Baldwin replaced the VO-660 with the model DS-4-4-660 in 1946.
The VO-1000 was built between January 1939 and December 1946. It was powered by a naturally aspirated eight cylinder engine rated at 1,000-horsepower (750 kW). Some had the Batz truck originally developed by the Atchison, Topeka and Santa Fe Railway as a leading truck for steam locomotives. 548 VO-1000s were built.
The DS-4-4-660 was built between 1946 and 1949. It replaced the 600-horsepower (450 kW) VO-660 as the low power companion to the DS-4-4-1000 models. 139 were built.
The DS-4-4-1000 was a 1,000-horsepower (750 kW) model built between 1946 and 1951. The first units (56 locomotives) were powered by an 8-cylinder normally aspirated prime mover, but from 1948 a change was made to a 6-cylinder turbocharged engine. A total of 502 were built.
==Original buyers==
Railroad 	Quantity	Road number 	Notes
Baldwin-Lima-Hamiton (demonstrators) 	2 	1200–1201 	to Rock Island 758–759
Atlanta and West Point Rail Road 	1 	678 	
Akron and Barberton Belt Railroad 	2 	27–27 	
American Smelting and Refining Company 	2 	1954–1955 	
Apache Railway 	1 	600 	
Armco Steel, Hamilton, Ohio 	1 	706 	
Baltimore and Ohio Railroad 	5 	463–467 	Renumbered 9274–9278
Calumet and Hecla Mining Company 	1 	203 	
Central of Georgia Railway 	4 	311–314 	
Central Railroad of New Jersey 	7 	1053–1059 	
Chicago and North Western Railway 	16 	1073–1076, 1106–1109, 1117–1121, 1126–1128	
Chicago, Milwaukee, St. Paul and Pacific Railroad ("Milwaukee Road")	21 	1905–1925 	Renumbered 900–914, 920–925 (not in order)
Copper Range Railroad 	1 	200 	
Erie Railroad 	12 	617–628 	
Erie Mining Company 	4 	400–403 	
Great Northern Railway 	5 	24–28 	
Kansas City Southern Railway 	4 	1160–1163 	
Lehigh Valley Railroad 	14 	230–243 	
Michigan Limestone 	2 	116–117 	
Missouri-Kansas-Texas Railroad 	15 	1201–1210 	Renumbered
Monongahela Railway 	27 	400–426 	
Missouri Pacific Railroad 	20 	9200–9219 	Renumbered 1260–1279
Missouri Pacific (International-Great Northern Railroad) 	10 	9220–9226, 9230–9232 	
Missouri Pacific (St. Louis, Brownsville and Mexico Railway) 	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 	2 	61–62 	
New York Central Railroad 	21 	9308–9328 	
Oliver Iron Mining Company 	1 	933 	
Patapsco and Back Rivers Railroad 	3 	345–347 	
Pennsylvania Railroad 	87 	8100–8104, 8732–8796, 8976–8993 	PRR Class BS-12m
Pennsylvania-Reading Seashore Lines 	11 	6017–6021, 6028–6033 	
Rayonier, Inc. 	2 	201–202 	
Seaboard Air Line Railroad 	10 	1462–1465, 1476–1481 	to Seaboard Coast Line Railroad 203–206, 217–222
Sierra Railroad 	2 	40, 42 	
Southern Railway 	10 	2290–2299 	
Southern Pacific Company 	56 	1442–1513, 1539–1550 	
Southern Pacific (Texas and New Orleans Railroad) 	3 	105–107 	
Tennessee Coal, Iron and Railroad Company 	8 	1200–1207 	
Tennessee Valley Authority 	4 	1–3, 200 	
Terminal Railroad Association of St. Louis 	4 	1250–1253 	
United States Air Force 	2 	1841–1842 	
United States Army 	1 	65-11391 	
United States Navy 	13 	65-00292–65-00294, 65-365–65-00374 	
U.S. Steel, Geneva Steel Works 	3 	33–35 	
U.S. Steel, Homestead Steel Works 	1 	GE1 	
U.S. Steel, Morrisville, Pennsylvania Works 	9 	GE2–GE8, GE17–GE18 	
Wabash Railroad 	5 	305–309 	
Total 	451 	 	
==Surviving units==
At least six intact examples of the S12 are known to survive at railroad museums. SMS Lines operates S12 #301 at the Penn Warner industrial park at Morrisville, Pennsylvania. One unit that was converted from a Baldwin DS-4-4-1000 is in service on the Whitewater Valley Railroad.
Only three intact examples of the VO-660 are known to survive, one of which was sold by the Altoona Railroaders Memorial Museum to SMS Lines to be repaired and put back into operation. The others are Pickens Railway #2, built in 1946, and Wyandotte Terminal 103, at the Illinois Railway Museum
There are at least eight intact examples of the VO-1000 that are known to survive, most of which are owned by museums or historical societies. A former SLSF unit that was repowered by EMD is owned by the Northwestern Pacific Railroad in Schellville, California.
A preserved S-12 #1200 is on display at the Railroad Museum of Pennsylvania.
== Gallery ==
File:1992-03-18 11 CWR S12 57 Willits CA Cliff West.jpg
File:Diesel Switcher No. 200.jpg
File:RR92.2 No. 1200 Side.JPG
==External links==
*Baldwin S-12
*Preserved Baldwin and Lima locomotives
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