EMD AEM7

EMD AEM-7
Amtrak AEM-7 No. 943 with a Metroliner at Seabrook, Maryland, in 1987
Type and origin Power type Electric Builder General Motors Electro-Motive Division Build date 1978–1988 Total produced 65 Rebuilder Alstom Rebuild date 1999–2002 Number rebuilt 29
Specifications Configuration: ​  • AAR B-B  • UIC Bo'Bo' Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Wheel diameter 51 1⁄8 in (1,299 mm) Wheelbase 25 ft 7 1⁄16 in (7.80 m) (between truck centers) Length 51 ft 1 25⁄32 in (15.590 m) Width 10 ft 2 in (3.10 m) Height 14 ft 9.5 in (4.51 m) Loco weight 101 short tons (90 long tons; 92 t) Power supply Catenary Electric system/s 11 kV 25 Hz AC 12.5 kV 60 Hz AC 25 kV 60 Hz AC Current pickup(s) Dual pantographs Traction motors ASEA LJH 108-5 (DC) Alstom 6 FXA 5856 (AC) Head end power 500 kilowatts (670 horsepower) (DC) 1,000 kilowatts (1,300 horsepower) (AC) Transmission 85:36 Train heating Locomotive-supplied head-end power
Performance figures Maximum speed 125 mph (201 km/h) Power output 7,000 hp (5.2 MW) Tractive effort: ​  • Starting 51,710 lbf (230 kN)  • Continuous 28,100 lbf (125 kN)
Career Operators Amtrak MARC SEPTA Numbers Amtrak: 900–953 MARC: 4900–4903 SEPTA: 2301–2307 Nicknames Toasters; Meatballs Locale Northeast United States Retired 2016 (Amtrak) 2017 (MARC) Preserved Amtrak No. 915

The AEM-7 is a twin-cab four-axle 7,000 hp (5.2 MW) B-B electric locomotive built by Electro-Motive Division (EMD) and ASEA between 1978 and 1988. The locomotive was a derivative of the Swedish SJ Rc4 designed for passenger service in the United States. The primary customer was Amtrak, which bought 54 for use on the Northeast Corridor and Keystone Corridor. Two commuter operators, MARC and SEPTA, also purchased locomotives, for a total of 65.

Amtrak ordered the AEM-7 after the failure of the GE E60 locomotive. The first locomotives entered service in 1980 and were an immediate success, ending a decade of uncertainty on the Northeast Corridor. In the late 1990s, Amtrak rebuilt 29 of its locomotives from DC to AC traction. The locomotives continued operating through the arrival of the final Siemens ACS-64 in June 2016. MARC retired its fleet in April 2017 in favor of diesel-electric Siemens Charger; SEPTA expects to replace its fleet with ACS-64 locomotives in 2018.

Amtrak assumed control of almost all private sector intercity passenger rail service in the United States on May 1, 1971, with a mandate to reverse decades of decline. Amtrak retained approximately 184 of the 440 trains which had run the day before. To operate these trains, Amtrak inherited a fleet of 300 locomotives (electric and diesel) and 1190 passenger cars, most of which dated from the 1940s–1950s.

Operation on the electrified portion of the Northeast Corridor was split between the Budd Metroliner electric multiple units and PRR GG1 locomotives. The latter were over 35 years old and restricted to 85 mph (137 km/h). Amtrak sought a replacement, but no United States manufacturer offered an electric passenger locomotive. Importing and adapting a European locomotive would require a three-year lead time. With few other options, Amtrak turned to GE to adapt the E60C freight locomotive for passenger service. GE delivered two models, the E60CP and the E60CH. However, the locomotives proved unsuitable for speeds above 90 mph (145 km/h), leaving Amtrak once again in need of a permanent solution.