In November, 1939, an unusual looking and largely experimental diesel-electric locomotive demonstrator rolled off the line at General Motors Electro-Motive Division's LaGange, Ill., plant. Few who saw it then could imagine the impact this uint would ultimately have on American railroading.
Today, on permanent display in the National Museum of Transport in St. Louis, par to that unit - Southern Railway No. 6100 - symbolizes the revolutionary shift in motive power that changed virtually every aspect of the railroad business. Appropriately, it has been designated a National Historic Mechanical Engineering Landmark by the American Society o f Mechanical Engineers.
Richard M. Dilworth, Electro-Motives's chief engineer, was the man behind the machine. His name is liked with early passenger diesel locomotives, and his is credited with many of the innovations that freed diesel locomotives from stem-era designs.
Mr. Dilworth speculated that a locomotive carrying two four wheel trucks with all axles powered would provide considerable more horsepower than the the-standard passenger locomotive configuration of two six-wheel trucks, each with a center idle axle. A cab axle booster semi-permanently coupled by a draw bar could equal the power of a 2-8-2 or even a 2-10-2 steam locomotive, in typically use then for freight runs.
To test his theory, Electro-Motive sent the new demonstrator No. 103 - actually tow cab-and -booster units - on an 84,000 mile cross country working rip over some of the most challenging rail routes in the nation. From Oakland and Seattle, through t Moffat Tunnel near Colorado's Great Divide to Southern Railway's famous "Rathole Division" in central Kentucky and East Tennessee, No. 103 met and overmatched the best performance steam could offer.
No. 103 ran freight hauls in 35 states, over the lines of 20 Class 1 railroads between November 1939, and October 1940. One after another of the roads challenged No. 103 with steep grades, tight curves, lengthy tunnels, extremes of temperature and just plain long hours.
On the Southerns's own Cincinnati, New Orleans and Texas Pacific subsidiary line between Cincinnati and Chattanooga - the "Rathole Division" No. 103 vastly out preformed the standard 2-8-2 steam locomotive's hauling capacity. The 2-8-2 could haul 3,000 or more tons on the outer thirds of the run but grades on the Danville, Ky., to Oakdale, Tenn., section cut the engine's rating nearly in half. No. 103 ran the entire Cincinnati to Chattanooga route carrying 4,000 tons - and cut an hour from the six - hour run between Danville and Oakdale.
The story was the same in test on the B&O Cumberland Division with its 2.2 percent grades, along Colorado's Moffatt Tunnel route with its 6.21 mile Moffatt Tunnel and 9,200 - foot elevations and through the Santa Fe's Tehachapi Pass in California. By the end of the 11-month test phase, the diesel's hauling power was uncontested.
The FT-series of locomotives that No. 103 spawned eventually could be found on all the major railroads, and they gave long and useful service to their owners.
No. 103 itself was purchased by Southern in May, 1941. After reconditioning, it was painted the Southern's Black and white livery and renumbered 6100, 6104, 6150, and 6151. It went in to regular services running out of Chattanogga.
After nearly 20 years of faithful service on Southern's CNO&TP line, No. 6100 was retired on March 8, 1960 at Spencer, N.C. Little more than a year later, the historic unit took up residence at the National Museum of transport in St. Louis. There it remains, surrounded by a number of steam locomotives it helped put out of business.
On June 26, 1982, No. 6100 was designated a National Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers The prototype of first mass-produced diesel-electric road freight locomotive is the 77th national land mark to be designate by the ASME since the program began in 1973.
James A. Bistline, general manager, Steam Operation, Norfolk Southern, represented Southern at ceremonies surrounding the ASME designation in June. "This locomotive represents the beginning of a long and progressive series of steps in modern railroading history," Mr. Bistline told the crowd. "It is truly the 'model T' of today's diesel fleets."