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Silver and blue locomotive
AEM-7 #915 on display at the Railroad Museum of Pennsylvania
Type and origin
Power type Electric
Builder General Motors Electro-Motive Division
Build date 1978–1988
Total produced 65
Rebuilder Alstom Transport
Rebuild date 1999-2002
Number rebuilt 29
 • AAR B-B
 • UIC Bo'Bo'
Gauge 4 ft 8 12 in (1,435 mm) standard gauge
Wheel diameter 51 18 in (1,299 mm)
Minimum curve 245 ft (75 m) / 23.4° (single unit)
265 ft (81 m) / 21.6° (coupled)
Wheelbase 25 ft 7 116 in (7.80 m) (between truck centers)
Length 51 ft 1 2532 in (15.590 m)
Width 10 ft 2 in (3.10 m)
Height 14 ft 9.5 in (4.51 m)
Axle load 51,225 lb (23,235 kg)
Adhesive weight 100%
Loco weight 204,900 lb (92,941 kg) max
Sandbox cap. 10.6 cubic feet (300 L)
Power supply Catenary
Electric system(s)
  • 11-13.5 kV 25 Hz AC
  • 11-13.5 kV 60 Hz AC
  • 25 kV 60 Hz AC
Current source 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
MU working yes
Train heating Locomotive-supplied head-end power
Loco brake Dynamic / Regenerative / Electropneumatic
Train brakes Electropneumatic
Safety systems ACSES II
Performance figures
Maximum speed 135 mph (217 km/h) (design)
125 mph (201 km/h) (operational)
Power output AEM-7DC and AC: 5,100 kilowatts (6,800 horsepower) maximum at rail
4,320 kilowatts (5,790 horsepower) continuous at rail[1][2]
Tractive effort Starting Tractive Effort:
53,924 lbf (239.9 kN) (DC)[2]
51,700 lbf (230.0 kN) to 43 mph (69 km/h) (AC)[3]
Continuous Tractive Effort:
30,000 lbf (133.4 kN) @ 77 mph (124 km/h) (DC)[4]
39,500 lbf (175.7 kN) @ 65 mph (105 km/h) (AC)
Factor of adh. ~ 3.85
Brakeforce 15,600 lbf (69.4 kN) (DC)
20,000 lbf (89.0 kN) (AC)
Nicknames Toasters; Meatballs
Locale Northeast Corridor, Keystone Corridor
Preserved Amtrak #915

The AEM-7 is a twin-cab B-B electric locomotive that was 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. EMD manufactured 65 locomotives between 1978–1988; the majority of these were for Amtrak, other operators included MARC and SEPTA. Amtrak has retired their fleet in favor of the newer Siemens ACS-64, which entered service in 2014; MARC and SEPTA plan to replace theirs between 2017–2019.


Swedish Rc4 imported and repainted in Amtrak's livery for evaluation. This locomotive performed well and would become the basis of the AEM-7.

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.[5] 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.[6]

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).[7] 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 E60 for passenger service.[8] Unfortunately, the E60 proved unsuitable for speeds above 90 mph (145 km/h), leaving Amtrak once again in need of a permanent solution.[9]

Amtrak now 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).[10] Amtrak favored the Swedish design, which became the basis for the AEM-7.[11]


The AEM-7 was smaller than its predecessors, the PRR GG1 and the GE E60. It measured 51 ft 1 2532 in (15.59 m) long by 10 ft 2 in (3.10 m) wide, and stood 14 ft 9.5 in (4.51 m) tall.[12] The AEM-7 weighs 101 short tons (90 long tons; 92 t), whereas the GG1 weighs 238 short tons (213 long tons; 216 t). With all the weight on eight drivers, the AEM-7 has a high horsepower to weight ratio (70 hp/short ton) and needs a sophisticated wheelslip control (Pressductor) system.[citation needed]

The Budd Company manufactured the carbodies for the initial Amtrak order; the Austrian firm Simmering-Graz-Pauker for the MARC order.[13]

The locomotive's head end power (HEP) was sufficient for 8-10 Amfleet cars.[14]


#939 was among the 29 units rebuilt as AEM-7ACs

In 1999, Amtrak and Alstom began a remanufacturing program for Amtrak AEM-7s. Alstom supplied AC propulsion equipment, electrical cabinets, transformers, HEP, and cab displays. The rebuild provided Amtrak with locomotives that had improved high end tractive effort and performance with longer trains. Amtrak workers performed the overhauls under Alstom supervision at Amtrak's shop in Wilmington, Delaware.[15] These remanufactured AEM-7s were designated AEM-7AC. Between 1999 and 2002, Amtrak rebuilt 29 AEM-7s.[16]

The power modules use water-cooled IGBT technology and provide about 5,000 kilowatts (6,700 horsepower) of traction power plus 1,000 kilowatts (1,300 horsepower) of HEP, an improvement over the 500 kilowatts (670 horsepower) HEP capacity of the original DC units, and enough for 18 Amfleet or Viewliner coaches. The traction motors (model 6 FXA 5856) are from Alstom's ONIX family of propulsion components, and have a maximum rating of 1,250 kilowatts (1,680 horsepower)-1,275 kilowatts (1,710 horsepower) and a continuous rating of 1,080 kilowatts (1,450 horsepower). Locomotive electric brake ratings are ~4,300 kilowatts (5,800 horsepower) in regenerative mode and ~2,200 kilowatts (3,000 horsepower) in rheostatic (resistor-only) mode. As such, the remanufactured AEM-7 was the world's first passenger locomotive with IGBT in service.[1][17]


The AEM-7 was replaced with the ACS-64 (pictured) between 2014 and 2016

Amtrak ordered 30 AEM-7s in 1977 and 17 more in 1980.[18] By 1978, the Electro-Motive Division of General Motors (EMD), now Electro Motive Diesel, began production. The bodies came from the Budd Company, with electrical, trucks and mechanical parts imported from Sweden. The first AEM-7 (900) went into service in 1979.[citation needed] The Swedish influence led to the nickname "Meatball", after Swedish meatballs. Railfans nicknamed the boxy locomotives "toasters."[19] Between 1980 and 1982, 46 AEM-7s (900-946) went into service. This helped retire the GG1s from regular service. Amtrak ordered seven more AEM-7s in 1987 (Order Number: 876006), which were completed by 1988.[citation needed] Two commuter operators in the Northeast ordered AEM-7s. MARC ordered four in 1986 for use on its Penn Line service on the Northeast Corridor between Washington, D.C. and Perryville, Maryland.[20] SEPTA ordered seven in 1987.[21]

In 2010 Amtrak ordered 70 Siemens ACS-64 locomotives to replace both the AEM-7s and the newer but unreliable Bombardier/Alstom HHP-8s.[22] The ACS-64s began entering revenue service in February 2014.[23] The last two active AEM-7s, 942 and 946, made their final run on June 18, 2016 on a special farewell excursion that ran between Washington, DC and Philadelphia.[24]

MARC ordered the Siemens Charger locomotive to replace their electric fleet consisting of AEM-7s and HHP-8s. All MARC-owned AEM-7s have been retired. MARC leased several Amtrak AEM-7ACs to fill the position of the MARC-owned units from mid 2015 to late 2016. On August 1, 2016, the final leased Amtrak unit, #946, made its last run with MARC on the Penn Line. The leased AEM-7ACs were replaced by 2 GE P42DCs leased from Amtrak.

SEPTA will replace their AEM-7s and single ALP-44 with the ACS-64 between 2018 and 2019.


One unit has been preserved. AEM-7 #915 was moved to the Railroad Museum of Pennsylvania in June 2015.[25]


  1. ^ a b "ALSTOM Transport - AEM7 locomotives, USA". alstom.com. Archived from the original on 25 March 2006. 
  2. ^ a b "Typbeskrivningar - AEM7 exporterade till Amtrak m fl". passagen.se. Archived from the original on 24 May 2002. 
  3. ^ http://www.sonic.net/~mly/Caltrain-Electrification/2000-08-Rolling-Stock-Draft/a7.pdf
  4. ^ http://i324.photobucket.com/albums/k329/mestevet/01671s11Kvsm.jpg
  5. ^ Kelly, John (June 5, 2001). "Amtrak's beginnings". Classic Trains. Retrieved September 13, 2016. 
  6. ^ Simon & Warner 2011, p. 108
  7. ^ GAO 1976, p. 29
  8. ^ GAO 1976, p. 30
  9. ^ USDOT 1978, p. 71
  10. ^ Tillier, Clem. "Amtrak's X996". Amtrak Historical Society. 
  11. ^ Cudahy 2002, pp. 85–86
  12. ^ Ephraim 1983, p. 51
  13. ^ Trains 1986, p. 13
  14. ^ Solomon 2014, p. 309
  15. ^ Vantuono, William C. (May 2000). "Get ready for a great ride". Railway Age. 201 (5): 43. 
  16. ^ "Delaware shops work to meet challenges of modern-day railroad" (PDF). Amtrak Ink. 8 (2): 3. March 2003. 
  17. ^ https://web.archive.org/web/20140804194342/http://www.uic.org/cdrom/2001/wcrr2001/pdf/sp/1_11/555.pdf Page 11
  18. ^ "EMD electric order numbers". Retrieved 2006-09-08. 
  19. ^ Laepple, Wayne (12 June 2015). "Amtrak AEM-7 arrives in Strasburg". Trains. Retrieved 12 June 2015.  (subscription required)
  20. ^ Middleton 1994, p. 15
  21. ^ Middleton 1994, p. 39
  22. ^ Amtrak (28 October 2010). "Amtrak Awards $466 Million Contract for 70 New Electric Locomotives". prnewswire.com. 
  23. ^ "NEW AMTRAK LOCOMOTIVES READY FOR SERVICE AND SET TO POWER NORTHEAST ECONOMY" (PDF) (Press release). Amtrak. 6 February 2014. Retrieved 4 March 2014. 
  24. ^ "Farewell to the AEM-7 Excursion Train" (Press release). Amtrak. Archived from the original on 25 April 2016. 
  25. ^ "Amtrak AEM-7 Locomotive Becomes Newest Additon to Railroad Museum of Pennsylvania's Historic Collection" (PDF) (Press release). Railroad Museum of Pennsylvania. June 12, 2015. 


Further reading[edit]

  • Ephraim, Max, Jr. (1982). "The AEM-7 - A New High-Speed, Light-Weight Electric Passenger Locomotive". ASME Paper: 1–7. ISSN 0402-1215. 82-RT-7. 

External links[edit]