survived in service until 1977. All of the Union Pacific "U-Boats" & Southern Pacific "Baby Hueys" were sold for scrap by 1977. See also Union Pacific GTELs EMD DD35A ALCO Century 855 References Mentions earlier UP GE purchases also. Diesel-electric locomotives of the United States U50 Union Pacific Railroad locomotives B+B-B+B locomotives Railway locomotives introduced in 1963 Scrapped locomotives Freight locomotives Standard gauge locomotives of the United States