GE U50

GE U50

U50 #50 on an eastbound freight at Laramie, Wyoming.

Type and origin Power type Diesel-electric Builder General Electric Model U50 Build date 1963 - 65 Total produced 26

Specifications Configuration: ​  • AAR B+B-B+B Gauge 4 ft 8 1⁄2 in (1,435 mm) Trucks 4 Length 83 ft 6.5 in (25.46 m) Prime mover Dual GE FDL-16 Engine type Diesel Traction motors 4 Transmission Diesel electric

Performance figures Power output 5,000 hp (3,700 kW)

Career Operators Union Pacific Railroad Southern Pacific Railroad Nicknames Baby Hueys Locale North America Disposition scrapped

The GE U50 was an eight-axle, 5,000 hp (3.7 MW) diesel-electric locomotive built by GE Rail. They were twin-engined locomotives, combining two 2,500 hp (1,900 kW) diesel engines.

The U50 rode on four two-axle trucks, grouped in pairs linked by span bolsters, giving a wheel arrangement of B+B-B+B. The trucks and bolsters were re-used from scrapped UP turbine locomotives built by GE during the 1950s. The U50 was built in response to the Union Pacific Railroad's requirement, issued in the early 1960s, for a 15,000 hp (11,200 kW) 3-unit locomotive intended to replace the turbines. The design was effectively two U25B locomotives on a single frame; each diesel engine and generator powered only the two trucks at the same end. Three were delivered to the UP in October 1963, and three to the Southern Pacific Railroad in May and June 1964. Other locomotives built to this requirement were the EMD DD35 and the ALCO Century 855.

The Southern Pacific kept the three but did not order any more. They were kept on the roster until the late 1970s, but were often sidelined. SP's units gained the nickname "Baby Hueys" from the cartoon character of the same name. Original numbers were #8500-8502; they were later renumbered #9950-9952. Southern Pacific's three units differed from the Union Pacific U50s by having a cab door and headlights in the hood beneath the front windows.

The Union Pacific was more satisfied with their three, and ordered 20 more. A batch of 12 were delivered between July and September 1964, while a final eight were built May through August 1965. They were numbered #31-53. UP #52 was delivered with a Cummins PT fuel system and rated at 5600 horsepower. The #52 had a standard fuel system installed in October 1966 and was rerated to 5000 horsepower.