EMD AEM-7

The AEM-7 is a twin-cab B-B electric locomotive that is used in the United States on the Northeast Corridor between Washington DC and Boston and the Keystone Corridor between Philadelphia and Harrisburg in Pennsylvania. They were built by Electro-Motive Division from 1978 to 1988. There are two versions of the AEM-7 as of 1999: the original AEM-7DC which has DC propulsion equipment and the newer, modified AEM-7AC which uses AC propulsion equipment. EMD manufactured 65 locomotives between 1978–1988; the majority of these were for Amtrak, other operators included MARC and SEPTA. Amtrak is phasing out its fleet in favor of the newer Siemens ACS-64, which entered service in 2014.

Background

Amtrak had inherited high-speed operations on the Northeast Corridor from the bankrupt Penn Central in 1971. Electrified passenger services between New York and Washington were handled by the new if unreliable Budd Metroliner electric multiple units and the aging PRR GG1s, originally built for the Pennsylvania Railroad in 1934–1943. Amtrak's first attempt at replacing the GG1 was the General Electric E60, delivered in 1974. The E60s proved unable to safely exceed 100 miles per hour (160 km/h) and Amtrak relegated them to hauling slower long-distance services. Amtrak turned to existing European high-speed designs, and two were brought over for trials in 1976–77: the Swedish Rc4 (numbered X995), and the French CC 21000 (X996). Amtrak favored the Swedish design, which became the basis for the AEM-7.