Baldwin S-12

The Baldwin S-12 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, S-12s were known for their "lugging" power, despite being temperamental. Like most Baldwin switchers, the S-12 had AAR Type-A switcher trucks in a B-B wheel arrangement. 451 units were built between 1951 and 1956, when Baldwin left the locomotive market.

Baldwin S-12
A preserved S-12 at the Railroad Museum of Pennsylvania.
Type and origin Power type Diesel-electric Builder Baldwin-Lima-Hamiton Model S-12 Build date January 1951–October 1956 Total produced 451
Specifications Configuration: ​  • AAR B-B Gauge 4 ft 8 ^1⁄2 in (1,435 mm) standard gauge Trucks AAR type A Wheel diameter 40 in (1,016 mm) Minimum curve 44° (133.47 ft or 40.68 m radius) Wheelbase 30 ft 8 in (9.35 m) Length 46 ft 6 ^1⁄4 in (14.18 m) Width 9 ft 11 ^1⁄4 in (3.03 m) Height 14 ft (4.27 m) Loco weight 240,000 lb (108,862 kg) Prime mover 606A RPM range 625 rpm max Engine type Four-stroke diesel Aspiration Turbocharged Displacement 1,979 cu in (32.43 l) per cylinder 11,874 cu in (194.58 l) total Generator Westinghouse 480DC Traction motors (4) Westinghouse 362-D Cylinders 6 Cylinder size 12 ^3⁄4 in × 15 ^1⁄2 in (324 mm × 394 mm)
Performance figures Maximum speed 60 mph (97 km/h) Power output 1,200 hp (895 kW) Tractive effort Starting: 72,000 lbf (33,000 kgf) @30% Continuous: 34,000 lbf (15,000 kgf) @10.8 mph (17.4 km/h)
Career Disposition 6 preserved, remainder scrapped

Balwin DS-4-4-660 / DS-4-4-1000
Type and origin Power type Diesel-electric Model DS-4-4-660 / DS-4-4-1000 Build date 660: June 1946 to May 1949 1000: January 1951 – November 1951 Total produced 660: 139 1000: 446
Specifications Configuration: ​  • AAR B-B Gauge 4 ft 8 ^1⁄2 in (1,435 mm) standard gauge Trucks AAR Type A truck Wheel diameter 36 in (914 mm) Minimum curve 44° (133.47 ft (40.68 m) radius) Wheelbase 30 ft 8 in (9.35 m) Length 46 ft 6 ^1⁄4 in (14.18 m) Width 9 ft 11 ^1⁄4 in (3.03 m) Height 14 ft (4.27 m) Loco weight 660: 196,600 lb (89,200 kg) 1000: 230,000 lb (100,000 kg) Prime mover 660: Baldwin 606NA 1000: 608NA later 606SC RPM range 625 rpm max. Engine type 606: Straight-6 608: Straight-8 Four-stroke diesel Aspiration 606NA and 608NA: Natural 606SC: Turbocharged Displacement 1,979 cu in (32.43 l) per cylinder 606: 11,874 cu in (194.58 l) total 608: 15,832 cu in (259.44 l) total Generator West’hse 480 DC Traction motors (4) West’hse 362-D Cylinders 6 Cylinder size 12 ^3⁄4 in × 15 ^1⁄2 in (324 mm × 394 mm) Loco brake Air Train brakes Air
Performance figures Power output 660: 660 hp (492 kW) 1000: 1,000 hp (746 kW) Tractive effort 660: 56,500 lb (25,600 kg) 1000: 57,500 lb (26,100 kg)
Career Locale North America

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 S-12 are known to survive at railroad museums. SMS Lines operates S-12 #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.

References

• Dorin, Patrick C. (1972). Chicago and North Western Power. Burbank, California: Superior Publishing. pp. 158, 161–163. ISBN 0-87564-715-4.
• Pinkpank, Jerry A (1973). The Second Diesel Spotter’s Guide. Kalmbach Books. pp. 282, 287–291. ISBN 0-89024-026-4. LCCN 66-22894.

External links

• Baldwin S-12
• Preserved Baldwin and Lima locomotives
• Locomotive Bogie Truck EMD#AARA, now CatepillarCo~MotivePowerInd