thanks - and to tell the truth - i wish it wasn't there - would make the scene more nostalgic looking ? i did capture 844 unassisted between Medicine Bow, WY and Hanna, WY last year on her way to Portland OR
i think the diesel is there for 2 things - safety - like if the have to un-hook for some reason and they'd have a back-up - if something happens to the steam locom. and to power the lights for the other cars ???
The EMD DDA40X was a 6,600 hp (4.9 MW) D-D diesel-electric locomotive built by the General Motors EMD division of La Grange, Illinois for the Union Pacific Railroad. Nicknamed "Centennial" and "Big Jack", it uses two diesel engines (each providing 3,300 hp (2.5 MW)), and although recent locomotive designs such as the AC6000CW and SD90MAC have come close, the DDA40X remains the most powerful single-unit diesel locomotive type ever built. It is also the longest single-unit diesel locomotive ever built. Taken from wikipedia. More here: [link]