A new Baldwin DR-12-8-1500/2 for Seaboard Air Line.

(Amarillo Globe Times, Public domain, via Wikimedia Commons)



The Baldwin DR-12-8-1500/2 (known informally as the Centipede) was the Baldwin Locomotive Works' first serious attempt at a production road diesel locomotive. The Baldwin type designation was 'DR-12-8-1500/2,' meaning Diesel Road locomotive, with 12 axles (8 of which were driven), and two engines of 1,500 horsepower (1,100 kW) each. The trucks were configured in a 2-D+D-2 AAR wheel arrangement. The nickname came from the numerous axles set in a nearly unbroken line, much like the legs of a centipede.


Drawing of a Baldwin Centipede diesel locomotive.

(Morven at English Wikipedia., CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons)



Built between December 1945 and July 1948, the "Babyface" design reflected Baldwin steam and electric locomotive practice. The carbody rode on two massive articulated cast steel half-frames cast by General Steel Castings, linked at the middle with a hinged joint. Unpowered four-wheel trucks at each end guided the locomotive through curves for stability at speed. Internal wiring was passed through metal conduits exactly like those used on a steam locomotive, which proved troublesome in practice.

The prototype 2-unit set was built in 1945 and toured American railroads. Orders followed from the Pennsylvania Railroad, the Seaboard Air Line Railroad, and the National Railways of Mexico (NdeM). The two demonstrators (originally ordered by Union Pacific Railroad as No. 998 and No. 999) were never sold and were eventually scrapped. The "Centipedes" were essentially obsolete during production, unable to compete with the more advanced locomotive design and technology offered by EMD. The N de M units reportedly arrived with parts missing. Reliability was an ongoing problem, and as they were built one at a time (like steam locomotives) each one was a bit different in the placement of wiring and equipment, which complicated even routine maintenance. The PRR units were eventually de-rated and relegated to helper service. Most PRR and SAL units were scrapped by the early 1960s, while NdeM units lasted slightly longer and were in service until the late 1960s. No Centipedes have been preserved.


Pennsylvania Railroad class BH50 locomotive.

Pennsylvania Railroad class BH50 locomotive - a Baldwin Centipede. Photographed at Horseshoe Curve near Altoona, Pennsylvania on July 15, 1953 by Otto Perry.

(Denver Public Library, https://en.wikipedia.org/wiki/File:PRR_BH50_x2.jpg, Fair use via Wikimedia Commons)


Original Buyers

Railroad Quantity Road numbers Notes
Union Pacific Railroad 2 998-999 Never sold
Baldwin Locomotive Works (demonstrators) 2 6000 A–B Not sold (Original UP 998-999)
Ferrocarriles Nacionales de México 14 6400–6413
Pennsylvania Railroad 24 5823A1,2–5834A1,2 Renumbered 5811–5834 (not in order)
Seaboard Air Line 14 4500-4513


In 1943 Baldwin built an experimental 6,000 horsepower (4,500 kW) "Centipede" as a demonstrator unit, which was assigned road No. 6000. The uniquely styled unit, with its upright, aggressive prow, also utilized the 2-D+D-2 wheel arrangement, but was to be powered with eight V8 8LV diesel engines, though only four were actually installed. The lone unit was classified by Baldwin as the

4-8-8-4-750/8DE1 and scrapped soon after production, and its running gear was used for the Seaboard Air Line’s first centipede No. 4500.


A photo of an N de M Baldwin Centipede, No. 6404. These were delivered from the factory with parts missing. Click to enlarge.

(Unknown photographer, W. Lenheim Collection)


Type and origin

Power type: Diesel-electric
Builder: Baldwin Locomotive Works
Model: DR-12-8-1500/2
Build date: December 1945 – July 1948
Total produced: 54
​• Whyte 4-8-8-4
• AAR 2-D+D-2
• UIC (2′Do)+(Do2′)
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Length: 91 ft 6 in (27.89 m)
Locomotive weight: 595,000 lb (269,900 kilograms)
Fuel capacity: 3,500 US gal (2,900 imp gal; 13,000 L)
Prime mover: 608SC x 2
Engine type: Four-stroke diesel
Aspiration: Turbocharger
Displacement: 15,832 cu in (259.44 L) (× 2)
Generator: Westinghouse 471A
Traction motors: Westinghouse 370F (8)
Cylinders: 8 (× 2)
Transmission: Electric
Locomotive brake: Straight air
Train brakes: Air
Performance figures
Maximum speed: 93 mph (150 km/h)
Power output: 3,000 hp (2.24 MW)
Tractive effort: 102,500 lbf (455.94 kN)
Operators: Pennsylvania Railroad, Seaboard Air Line, National Railways of Mexico
Class: PRR- BP60; NdeM- DE-12
Locale: North America
Disposition: All scrapped


A postcard photo of the PRR's Gotham Limited, led by Baldwin "Centipedes", on Horseshoe Curve in 1953.

(McLeod Photos, Oakdale, PA, Public domain, via Wikimedia Commons)