The DR-12-8-3000 "Centipede"

Header Photo: Drew Jacksich


The Baldwin Centipede, technically listed by the builder as a DR-12-8-3000 or DR-12-8-1500/2, was perhaps the most unique diesel-electric locomotive ever built. Constructed during Baldwin's early years of diesel development the radical design was more on par with electric locomotives with the model's odd wheel configuration. Surprisingly, several units were built for a handful of railroads although as became common with Baldwin-built diesels the DR-12-8-3000 proved troublesome in service and difficult to maintain. By the 1950s most railroads had scrapped their Centipedes due to the locomotives' troublesome prime mover, difficulty to maintain, and the damage it caused to the track structure. Today, none of the DR-12-8-3000 designs are known to be preserved as most were scrapped before the 1960s. From a historical standpoint this is a shame considering the distinction these locomotives hold in industry, even though they were unsuccessful.














The Baldwin Centipede gained its name from its odd wheel arrangement, which resembled the legs of a centipede. The DR-12-8-3000 featured an electric locomotive undercarriage of a 2-D+D-2 wheel arrangement. These odd sets of numbers and letters designate powered and unpowered axles. Unpowered axles are designated using numerals whereas powered axles are distinguished by using letters, typical in electric wheel arrangements. So, for instance, in a 2-D+D-2 arrangement the "2" refers to two unpowered axles front and aft and the “D” refers to four powered axles whereby “A” equals one powered axle, “B” equals two powered axles, “C” equals three powered axles, and so on.





Using Baldwin's rating system, however, the Centipede was a DR-12-8-3000. Breaking down the designations the DR referred to Diesel Road unit; the first number, 12, was the designation of twelve overall axles; the second number, 8, was the designation of eight powered traction motors; and 3,000 stood for the horsepower rating (in later models Baldwin would shorten the horsepower number to include only the first two digits of the rating so a 2,000 horsepower unit like the "Babyface" model would be DR6-4-20). Given the locomotive's numerous wheels and extremely heavy weight (593.71 tons) it probably comes as little surprise that it offered the highest tractive effort of any diesel locomotive in history; 205,000 pounds starting and 105,600 pounds continuous.

Seaboard Air Line DR-12-8-3000 "Centipede," #4500, is seen here in Florida during early December of 1945, shortly before entering service between Jacksonville and St. Petersburg. This unit was rebuilt from the original #6000 demonstrator.

The Baldwin Centipede, using the builder's infamous "Baby Face" carbody design, began production in December, 1945 using two demonstrators assigned to the Union Pacific. It was a massive locomotive using two 606 SC model prime movers that, again, produced 3,000 horsepower with a length of 91 feet. Surprisingly, the DR-12-8-3000 sold relatively well initially, as railroads were impressed with the incredible tractive effort it offered. The Pennsylvania and Seaboard Air Line railroads, who were quite loyal to Baldwin, purchased several units. The PRR would eventually buy 24 while Seaboard picked up 14. Although PRR and SAL were the only two American lines to purchase the Centipede National de Mexico also bought 14. Along with the two demonstrators, of which UP ultimately declined to buy, 54 total DR-12-8-3000s were built by the time production had ended in 1948.  

Ferrocarriles Nacionales de México (NdeM) DR-12-8-3000 "Centipede" #6401, out-shopped by Baldwin in early 1948. César Martínez Ávila collection.

Baldwin DR-12-8-3000/Centipede Production Roster

Owner Road Number(s) Quantity Date Built
Baldwin (Demo)6000A-6000B21948
National de Mexico (Mexico)6400-6413141947-1948
Pennsylvania5823A1-5834A1, 5823A2-5834A2241947-1948
Seaboard Air Line4500-4513141947-1948


Aside from the Centipede's maintenance and over-the-road troubles (to make matters worse, each order was customized with components placed in different areas of the locomotive making maintenance a headache), the model's weight caused significant wear to track. Additionally, its lack of dynamic braking made it difficult for use in heavy drag service along with the fact that Baldwin did not make it MU-capable (meaning it could not be operated directly from a lead locomotive).  Lastly, for more information about the Centipedes and please refer to the chart above for a complete production roster.




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