The Baldwin S-12

The Baldwin S-12 was an upgraded version of its predecessor, the S-8 although both models were built at the same time. Similar in size and mechanics, save for increased horsepower, this final switcher model built during the 1950s sold relatively well for the company as numerous Class Is, industries, and smaller railroads purchased the model. While the locomotive did have some complaints with its reliability it was revered for its ability to out-pull nearly any model in its class. The S-12 also saw Baldwin do away with the earlier complicated classification system, instead using one that involved simply the motive power type and horsepower rating. Today, the S-12 is one of Baldwin's best preserved diesel locomotives with at least fifteen still known to be in existence; seven at museums or tourist lines and eight more owned by shortline SMS Lines.

Milwaukee Road S12 #909 is seen here in Hastings, Minnesota on June 24, 1964.

The Baldwin S-12 switcher locomotive 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 the Westinghouse Electric Company, a long time supplier of internal components for Baldwin diesels (the two companies had also collaborated on several electric locomotives dating back to the 19th century). In any event, due to the S-12's increased horsepower it sold much better than its less powerful counterpart. At 1,200 horsepower using Baldwin's latest prime mover, the 606A SC railroads found the S-12 quite versatile in several applications from yard and industrial work to revenue service on, mostly, secondary and branch lines.

The locomotive came equipped with a standard four axle, B-B truck setup and could produce a hefty 72,000 pounds of starting tractive effort (34,000 pounds continuous). As mentioned above, Westinghouse provided all of the S-12's internal parts. When production had ended on the S-12 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 Smeting and Refining Company, Erie Mining, and others. In total, Baldwin sold 451 examples of the S-12.

Great Northern S12 #24 works the Minneapolis yard on June 14, 1964.

The S-12 was certainly Baldwin's most popular switcher in terms of its horsepower rating, general reliability, and its ability to pull almost anything. This is a significant reason why the model continues to find use in shortline service today, notably on shortline SMS Lines which owns eight; Michigan Limestone #116, Tennessee Valley Authority #200, U.S. Navy #65-00372, demonstrator #1200, SP #1547, and Erie Mining units #7241, Monongahela Railway #425, and Great Northern #27. While four of these locomotives are operational, four are also used for parts. To learn more about these units please click here.  Additionally, seven can be found at museums; Patapsco & Back Rivers #345-#346, Erie Mining #403, NYC #9313, SP #1550, Texas & New Orleans (SP) #121, and Oliver Iron Mining #933. Also, for a total production roster of Baldwin S-12s please click here. Finally, for more information about the S-12s and all Baldwin switcher models please refer to the chart below.

Baldwin Switchers

Lehigh Valley S12 #232 runs light through Wilkes-Barre, Pennsylvania on June 12, 1972.

For more information on the Baldwin S-12 switcher locomotive consider Mike Schafer’s Vintage Diesel Locomotives which looks at virtually all of the classic builders and models from Alco PAs to early EMD Geeps. If you’re interested in classic Baldwins, or diesels in general, this book gives an excellent general history of both.  You may also want to consider the book Evolution of the American Diesel Locomotive by author J. Parker Lamb. As the title implies the book looks at the history and development of the diesel locomotives, covering 200 pages, from its earliest beginnings to the newest designs and models operated today. If you're interested in perhaps purchasing either (or both) of these books please visit the links below which will take you to ordering information through Amazon.com, the trusted online shopping network.