Baldwin S-12

The Baldwin S-12 or BLH S12 is a diesel-electric switcher locomotive. 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 . 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 . 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 VO-660 as the low power companion to the DS-4-4-1000 models. 139 were built.

The DS-4-4-1000 was a 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	27-28
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
Chicago Burlington and Quincy	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 of Memphis)	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 9 intact examples (as well as 1 conversion) of the S12 are known to survive at railroad museums and freight operations. SMS Lines owns 9 S12's and operates #301 at the Penn Warner industrial park in Morrisville, Pennsylvania, as well as #304 on the Woodstown Central in Salem County, New Jersey with 7 others in storage or awaiting restoration. One unit that was converted from a Baldwin DS-4-4-1000 is in service on the Whitewater Valley Railroad.

The US Navy operates two S12's (nos. 65-00367 and 65-00368) at Naval Weapons Station Earle in Monmouth County, New Jersey

References

• Template:Dorin-North Western

External links

• Baldwin S-12