The Alp 46 was not available when HHP-8 was purchased, and since kassel plant in Germany is now Bombardier they would still need to buy from Bombardier.
From
www.gobytrain.com
650 to 662, 664
HHP-8s along with AEM-7’s work most trains on the Washington DC - New York - Boston corridor and on the Harrisburg line. All are fitted with ACSES.
AEM-7AC and HHP-8 types are operationally interchangeable.
Until October 2006 they were maintained by Northeast Corridor Maintenance Service Company (NECMSC).
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650 V NE WAS
651 V NE WAS
652 V NE WAS
653 V NE WAS
654 V NE WAS
655 V NE WAS
656 V NE WAS
657 V NE WAS
658 V NE WAS
659 V NE WAS
660 V NE WAS
661 V NE WAS
662 V NE WAS
663 V SU (out of service from August 2005)
664 V NE WAS (collision, Baltimore, 16 June 2006)