Bombardier-Alstom HHP-8

The Bombardier-Alstom HHP-8, for High Horse Power 8000, is a twin-cab electric locomotive built for Amtrak and MARC by a consortium of Bombardier and Alstom, with an electrical system based on Alstom's BB 36000 locomotive. Because of a limited number of locomotives produced and reliability issues that led to high maintenance costs, Amtrak retired all its HHP-8s after only 15 years of service, while MARC initially planned to follow suit but ultimately chose to refurbish its HHP-8 fleet between 2017 and 2018. In the 1990s Amtrak rebuilt and electrified the Boston route as part of the project that established Acela Express service, and chose Bombardier and Alstom, makers of the Acela Express, to produce a visually similar derivative for conventional service. The HHP-8 measures 67 feet 1 inch long and weighs 220,000 pounds, with a stainless steel carbody and a 6 MJ crash energy absorbance structure, and four 1.5 megawatt three-phase asynchronous traction motors fed by GTO inverters. Amtrak ordered 15 HHP-8s in 1996 and they were completed between 1999 and 2001, and MARC also acquired six. The locomotives were designed for up to 135 mph operation but are limited in service to 125 mph.