Prototype

UP's Centennials (EMD DD40's) and its' DD35 predecessors are fairly well known. Less well known are the GE competitors which were tried at the same time. The U50 had similar dual prime mover configuration but instead they came in a B-B+B-B wheel arrangement. These did not last long. The next batch from GE came in a C-C arrangement conveniently call the U50C.

I also have a photo of a U50 with it's little brother U25. [link]