While Electro-Motive's four-unit FT is often touted as "the diesel that did it" - vanquished the steam locomotive - it was the lowly switcher that launched the initial assault on steam and made the FT's victory possible. The first commercially successful diesel-electric, Central of New Jersey No. 1000, was a 300 hp boxcab switcher; it came off the American Locomotive Company's Schenectady, N.Y. erecting floor in 1925. To make that landmark engine possible, Alco, the nation's second-largest steam locomotive builder, had teamed up with Ingersoll-Rand, which supplied the diesel motor, and General Electric, which built the generator and traction motors.
Three years later, Alco acquired an established diesel motor company; its largest steam competitor, Baldwin, would later make the same move. In Alco's case the firm was McIntosh & Seymour of Auburn, N.Y., an industry leader in stationary and marine engines. While the nascent diesel technology was not yet ready to power road locomotives, the early 300-600 hp motors proved ideal for yard work. Compared to the 0-6-0s and similar switchers they replaced, the new diesels were easier to operate and fuel, required significantly less down time for maintenance, and spewed a lot less soot into the urban areas where most of them worked.
Almost from the beginning, Alco recognized the need to give its new technology a semblance of style. Later dubbed "HH" models by railfans (for "high hood"), Alco switchers of the mid and late 1930s were styled by industrial designer Otto Kuhler. The high hood, which reached almost to the cab roof, was necessitated by the height of the McIntosh & Seymour model 531 and 538 inline 6-cylinder four-stroke diesel motors, which displaced 1,595 cubic inches per cylinder. (Compare this with 567 cu.in. per cylinder in the Electro-Motive FT's 16-cylinder two-stoke diesel.) In those early days of a radical new technology, it was not uncommon for Alco HH engines to demonstate on a new railroad and be purchased almost immediately.
Electro-Motive, meanwhile, introduced its SW1 switcher in 1939, with a lower hood and more cab windows that allowed it to brag about "full front vision." In response, Alco redesigned its engine mounts to allow the motor to drop into a recess in the frame and in 1940 introduced its S-1 and S-2 switchers, with a greenhouse-like cab that offered ample crew visibility in all directions. The same year, Alco formalized a relationship with GE to market diesels under the Alco-GE banner - so this time it was GE designer Ray Patten who designed the new locomotives, rounding the corners and applying Art Deco touches. Six years and a World War later, Patten would become more well-known as the designer of Alco's PA passenger diesel, still widely regarded as the most beautiful of first-generation diesels.
Alco's S-1 and S-2 differed mainly in power output. The normally aspirated S-1 with 600 h.p. booted many a small steam switcher from railroad rosters coast to coast. Turbocharging gave the S-2 1000 h.p., allowing it to replace larger steam switchers and branch line engines like 2-6-0s, 2-8-0s and 2-8-2s.
Like most Alco switchers of the '30s and '40s, the S-series rode on Alco's own Blunt trucks, named for the in-house engineer who designed them to negotiate the tight turns and less-than-perfect track often found on switching assignments. A decade later, Alco would join the rest of the industry in adopting the "Recommended Practice" American Association of Railroads (AAR) Type A switcher truck for its updated S-3 and S-4 models - although many old hands felt the Blunt truck rode smoother and tracked better.
In contrast with earlier high-hood models, which had the radiator next to the cab and the diesel-driven generator at the front of the locomotive, the S-series featured the internal layout that was becoming standard for diesel switchers of all makes. The radiator was at the front of the engine, followed by the diesel motor itself and lastly the main generator. This placed the generator next to the electrical controls in the cab, and minimized both electric cable and cooling pipe runs.
Introduced just in time for World War II's crush of traffic, the S-2 became a best-seller. Rare was the Class 1 railroad that did not own a fleet of them, and short lines coast-to-coast rostered them as well. By the end of production in 1950, more than 1500 S-2s had been delivered. The near-identical S-4, riding on AAR trucks, would continue in production for another seven years and nearly 800 engines, at Alco's Schenectady plant and its Canadian subsidiary, Montreal Locomotive Works. The engines proved extremely durable, with many earning their keep into the 1970s and '80s, and a number still operating today in tourist railroad and short line service. Like most Alco engines with turbochargers, S-2s are known by railfans as "honorary steam locomotives" for the bursts of smoke they emit when their turbochargers rev up on acceleration.
Our S-2 model rides on prototypical Blunt trucks and features everything you'd want in a hard-working switcher. Walkways have metal handrails and etched safety tread to prevent your 1/48-scale crewmen from slipping on a wet surface. End pilots have separately-added uncoupling levers. On the cab sides you'll find legible Alco builder's plates, and a cooling fan is visible beneath the see-through metal grille atop the hood. The numerous grab irons and under-frame bell are also separately added metal parts, and the cab features an illuminated interior with two crewmen. Directionally operated headlights and illuminated number boards round out the lighting effects.
Dual pickup rollers on each truck make this model nearly stall-proof on any three-rail O gauge switches. Throttle down as low as three scale miles per hour and maintain that speed as long as you wish, thanks to Proto-Speed Control. Pick up and drop off cars anywhere on your layout, with remotely operated front and rear Proto-Couplers. Listen to the authentic chant of a first-generation Alco motor, rumbling with an off-beat gait that sounds like it could use a tune-up. Simulate light or heavy diesel exhaust with the variable-intensity ProtoSmoke system. While other manufacturers have offered the S-2, no other O gauge model runs more smoothly or dependably, sounds as good, or is more fun to operate.
In 1941, responding to a request from the Rock Island railroad for a branch line engine, Alco mounted the S-2 machinery on a stretched frame and added a second, shorter hood behind the cab to house a steam boiler for passenger train heat. The new RS-1 locomotive pioneered the multi-purpose "road switcher" concept - which would later replace covered-wagon style diesels like E-units and F-units and define a new look for American freight diesels that endures to this day.