The Baldwin S-12 or BLH S12 is a diesel-electric switcher locomotive. Powered by a turbocharged 6-cylinder version of the 606A diesel prime mover, S12s were known for their "lugging" power, despite being temperamental. Like most Baldwin-Lima-Hamilton 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 NotesBaldwin-Lima-Hamiton (demonstrators) 2 1200–1201 to Rock Island 758–759Atlanta 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 9274–9278Calumet 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 Renumbered 7240–7243. 403 last locomotive shipped by BLHGreat 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 RenumberedMonongahela Railway 27 400–426 Missouri Pacific Railroad 20 9200–9219 Renumbered 1260–1279Missouri 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-12mPennsylvania-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, 217–222Sierra 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 Many S-12s survive today, both in revenue service and at museums and tourist operations.

Revenue Service

SMS Lines owns 9 S-12'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. 7 others are in storage or awaiting restoration.

The US Navy operates two S-12's (nos. 65-00367 and 65-00368) at Naval Weapons Station Earle in Monmouth County, New Jersey

Preservation

Baldwin Locomotive Works #1200 is preserved at the Railroad Museum of Pennsylvania in Strasburg, Pennsylvania. Erie Mining #7243 is preserved at the Lake Superior Railroad Museum in Duluth, Minnesota. Nevada Northern #802 is stored at the Nevada Northern Railway Museum in Ely, Nevada. It was built in 1952 by Baldwin-Lima-Hamilton for New York Central as #9313, becoming Penn Central #8097. It was sold to Kennecott Copper Corporation in 1969 and used as a switcher at the McGill smelter as #802 and later donated to the museum. Patapsco & Back Rivers #335 (converted from a DS-4-4-1000) is preserved as Amherst Industries #99 at the Whitewater Valley Railroad in Connersville, Indiana. Patapsco & Back Rivers #346 is preserved at the Whitewater Valley Railroad in Connersville, Indiana. Southern Pacific #1550 is stored awaiting restoration at the Southern California Railway Museum in Perris, California.

References

External links

Baldwin S-12