Amtrak locomotive #626 at Union Station in Washington, DC.

Amtrak #626 is a Siemens ACS–64 (also known as the "Amtrak Cities Sprinter"). The ACS–64 is an electric locomotive operated by Amtrak in the Northeast Corridor.

The first Amtrak ACS–64 entered service in February of 2014. It can accelerate 18 Amfleet cars to maximum speeds as high as 125 mph in the Northeast Corridor in a little more than 8 minutes.

The design is based on the EuroSprinter and the Vectron platforms, which Siemens sells in Europe and Asia. Significant structural changes to the design were made to comply with American crashworthiness requirements, including the addition of crumple zones and anti-climbing features as well as structural strengthening of the cab, resulting in a heavier locomotive than the previous models. The body is a monocoque structure with integral frames and sidewalls.

The ACS–64 has advanced safety systems, including specialized couplers designed to keep trains from rolling over, jackknifing, or derailing during a collision. Additionally, they are more energy-efficient than the older models Amtrak operated in the Northeast Corridor. They lack dynamic braking grids in favor of 100% regenerative braking, depending on grid receptiveness. Energy generated from the brake may also be utilized to meet HEP needs, further reducing current draw from the grid.

Siemens ACS-64, https://en.wikipedia.org/w/index.php?title=Siemens_ACS-64&oldid=722367613 (last visited June 2, 2016).