The contract comprises a base order for 10 units with an option for up to 10 additional locomotives. Metrolink has allocated $US 129.4m for the acquisition.

The first three demonstrator locomotives will be delivered in the third quarter of 2015 and will help Metrolink to become one of the first operators in the United States to meet the latest Federal Environmental Protection Agency (EPA) emissions standards.

The locomotives will allow Metrolink to evaluate alternative fuel technologies which will become available over the next decade, and with higher output than existing locomotives in the fleet they will support the operation of longer trains.