The first units from the $US 466m order for 70 locomotives will undergo trials this summer and are due to enter revenue service in the autumn, augmenting and eventually replacing AEM7 locomotives built between 1978 and 1988.

Two pre-series locomotives will be tested at the TTCI test track in Pueblo, Colorado, while a third unit will be sent to the Northeast Corridor for mainline testing. The remaining 67 locomotives will be delivered to Amtrak by 2016.

The 6.4MW Bo-Bo locomotives will operate at up to 200km/h on regional and long-distance services on the Northeast Corridor between Boston, New York and Washington, DC, and up to 177km/h on Keystone Corridor trains between Philadelphia and Harrisburg, Pennsylvania.

The Cities Sprinter is based on Siemens' Eurosprinter and Vectron designs, and meets the latest Federal Railroad Administration safety and crashworthiness standards. The tri-voltage locomotives have a reinforced bodyshell with crumple zones to absorb energy in the event of a collision.