A typical Union Pacific GE U50C.

The GE; General Electric; U50C was a large 5,000hp twin-engine (consisting of two 2,500hp engines) six-axle diesel locomotive built from 1969 to 1971.

Forty U50Cs were built; all for Union Pacific. All units have been scrapped.


The GE U50C was a revolutionary type of diesel locomotive produced by GE; being one of the largest types as well as being a type of "double-diesel" (twin engined) model; which was first produced by their long-time rival, EMD with their revolutionary DD35 eight-axle model.  It is also a variant of the original GE U50. Like the EMD "Double-Diesel" super-powered diesel locomotive types (DD35 and DDA40X), they had twin engines which were very reliable, but were often plagued with other issues and problems which resulted in a short-lived lifetime. The type of locomotive proved to be successful at first because of its unique design, but eventually suffered from countless issues and problems involving the cab safety; and its unusual design was disliked by many railroad employees, as well as engine reliability being very poor which caused them to retire after only a few years of service, while some orders were even cancelled when GE applied UP and SP paint coats and numbering right at the last second (to whom these served as demonstrators as a result of a trade-in from the UP before ultimately being scrapped; besides the unfinished SP units were used as a basis for the U30C and other succeeding single-engined models).

They were some of the most short-lived diesel locomotives owned by the UP and SP, as well as being some of the most unsuccessful locomotive types produced by GE (their failure resulted in malfunctioning traction motors, crankshaft failures, high fuel consumption, and faulty wiring).


  • The GE U50C is part of GE's "Universal Series" of locomotives, which were and are often nicknamed "U-Boats" by railfans.