ALCO RSD-15

ALCO RSD-15
Green Bay and Western 2407, preserved at the Illinois Railway Museum
Type and origin Power type Diesel-electric Builder Alco Model DL600B Build date August 1956 – June 1960 Total produced 75
Specifications Configuration: ​  • AAR C-C  • UIC Co′Co′ Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Trucks Alco trimount Wheel diameter 40 in (1,016 mm) Length 66 ft 7 in (20.29 m)[1] Width 10 ft 2 in (3.10 m) Height 14 ft 11 in (4.55 m) Loco weight 335,000 lb (151,953.4 kg) Fuel capacity 3,350 US gallons (12,700 L; 2,790 imp gal) Prime mover Alco 251B Engine type V16 Four-stroke diesel Generator GE GT586 Traction motors GE 752 (6x) Cylinders 16
Performance figures Maximum speed 65 mph (105 km/h) Power output 2,400 hp (1.79 MW) Tractive effort Starting: 95,600 lbf (425.2 kN) at 25% adhesion; Continuous: 79,500 lbf (353.6 kN) at 12 mph (19 km/h)

The ALCO RSD-15 is a diesel-electric locomotive built by the American Locomotive Company (ALCO) of Schenectady, New York between August 1956 and June 1960, during which time 75 locomotives were produced. The RSD-15 was powered by an ALCO 251 16-cylinder four-cycle V-type prime mover rated at 2,400 horsepower (1.79 MW); it superseded the almost identical ALCO 244-engined RSD-7, and was catalogued alongside the similar but smaller 1,800 hp (1.34 MW) RSD-12, powered by a 12-cylinder 251-model V-type diesel engine.^[2]

The locomotive rode on a pair of three-axle Trimount trucks with all axles powered by General Electric model 752 traction motors. These trucks have an asymmetrical axle spacing because of the positioning of the traction motors. The six-motor design allowed higher tractive effort at lower speeds than an otherwise similar four-motor design.

The RSD-15 could be ordered with either a high or low short hood; railfans dubbed the low short hood version "Alligators", due to their unusually long low noses.