GE U50C

The GE U50C was a 5,000 horsepower diesel-electric locomotive that General Electric built for the Union Pacific in 1969 to 1971, forty units in all, numbered 5000 to 5039. Each used two 2,500 horsepower 12-cylinder diesel engines and rode on two three-axle trucks, reusing trucks taken from the railroad's retired gas turbine locomotives, in place of the eight-axle layout of the earlier U50. It was built to the same Union Pacific specification that produced the EMD DDA40X Centennial, a need for high power at speed. The weight-saving design was unsuccessful: aluminum wiring overheated and caused electrical fires, cast truck frames cracked, and engines and cooling systems failed often. Service ended after a business downturn in 1976, and all forty units were sold for scrap in 1977 and 1978, after five were lent out as stationary generators during a 1978 coal strike.