The SD70ACe is Electro-Motive Diesel's hope for the future. While designed to meet the Environmental Protection Agency's Tier-2 emissions requirements that took effect on January 1, 2005, this replacement for the SD70MAC also has a higher purpose: to recapture the lead in North American locomotive sales that EMD lost to General Electric in 1987.
Under the hood beats a third-generation model 710 diesel with 4300 horsepower; only slight modifications were needed to make the existing model 710 meet new emission standards. With 5000 such motors in service worldwide and a reputation for dependability, EMD reasoned that shop crews would prefer familiar technology.
Other than the prime mover, however, virtually every element of the SD70ACe has been re-thought to create a 21st century locomotive. Ergonomics were a prime consideration. The engine's angular nose offers the crew far better visibility than most other locomotives, and the cab is comfortable for engineers of almost any size. Digital screens provide a range of information on what is happening both inside the locomotive and out on the road. The cab easily accommodates a crew of three - an important factor in a modern world without cabooses. And there is, of course, a cupholder for the engineer.
The SD70ACe also offers, in EMD's words, "outstanding improvements in maintainability." All electrical wires are on the right side of the locomotive and all piping is on the left, with most pipes and wires routed under the frame so they can be serviced by a man standing outside the engine - rather than crawling around at the bottom of the engine room. And the time between service intervals has been doubled, from every three months to every six months.
After a year of testing on the road and at the Association of American Railroads' test track in Pueblo, CO, the first SD70ACe's ('e" stands for "enhanced") were delivered to CSX Transportation in 2004. Today they are rostered by nearly every North American Class 1 railroad. At the present time, mainline American railroads generally maintain dual fleets of locomotives. AC power is used for heavy coal hauling and hotshot intermodal traffic because AC traction motors offer higher starting tractive effort with the same horsepower. Less expensive, traditional DC power is used for more mundane duties. But with the SD70ACe, Electro-Motive hopes it may have the 21st Century successor to its 1949 Geep - a locomotive that can be nearly all things to all railroads.
Did you know?
IntelliTrain, an option on the SD70ACe, uses cellular and GPS technology to allow a railroad's maintenance department to monitor operating conditions and problems as they occur out on the road - making diagnosis and repair considerably easier.