GE U50
Encyclopedia
The GE U50 was an eight-axle, 5000 hp diesel locomotive built by GE Transportation Systems
. They were twin-engined locomotives, combining two 2,500 hp (1,850 kW) diesel engines.
, grouped in pairs linked by span bolster
s, 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 (11,100 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. 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.
Most were withdrawn from service in 1973 and 1974 and traded-in to GE for more modern high-powered units, although Southern Pacific's three survived in service until 1977.
The U50 is sometimes inaccurately referred to as the U50D, a back-formation from the U50C
name given to the six-axle units. The name is incorrect and was never used by the manufacturer or the railroad. The U50 did not ride on D trucks in any case. It is also sometimes referred to as the U50B, but this is incorrect as well. Some references erroneously give the wheel arrangement as B-B+B-B.
GE Transportation Systems
GE Transportation, formerly known as GE Rail, is a division of General Electric. The organization manufactures equipment for the railroad, marine, mining, drilling and energy generation industries. It is based in Erie, Pennsylvania. Locomotives are assembled at the Erie plant, while engine...
. They were twin-engined locomotives, combining two 2,500 hp (1,850 kW) diesel engines.
Configuration
The U50 rode on four two-axle trucksBogie
A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage/car or locomotive, or sprung as in the suspension of a caterpillar...
, grouped in pairs linked by span bolster
Span bolster
A span bolster, in rail terminology, is a beam or frame used to link two trucks or bogies so that they can be articulated together and be joined to the locomotive or railroad car at one rotating mounting point...
s, giving a wheel arrangement
Wheel arrangement
In rail transport, a wheel arrangement is a system of classifying the way in which wheels are distributed beneath a locomotive.. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and connections, with the adopted notations varying by country...
of B+B-B+B. The trucks and bolsters were re-used from scrapped UP turbine locomotives
Union Pacific GTELs
Union Pacific operated the largest fleet of gas turbine-electric locomotives of any railroad in the world. The prototype, UP 50 was the first in a series built by General Electric for Union Pacific's long-haul cargo services. The prototype was introduced in 1948 and was followed by three series...
built by GE during the 1950s. The U50 was built in response to the Union Pacific Railroad
Union Pacific Railroad
The Union Pacific Railroad , headquartered in Omaha, Nebraska, is the largest railroad network in the United States. James R. Young is president, CEO and Chairman....
's requirement, issued in the early 1960s, for a 15,000 hp (11,100 kW) 3-unit locomotive intended to replace the turbines. The design was effectively two U25B
GE U25B
The GE U25B was General Electric's first independent entry into the United States domestic diesel-electric railroad locomotive market for heavy production road locomotives since 1936...
locomotives on a single frame; each diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
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
Southern Pacific Railroad
The Southern Pacific Transportation Company , earlier Southern Pacific Railroad and Southern Pacific Company, and usually simply called the Southern Pacific or Espee, was an American railroad....
in May and June 1964. Other locomotives built to this requirement were the EMD DD35
EMD DD35
The EMD DD35 was a diesel-electric locomotive of D-D wheel arrangement built by General Motors Electro-Motive Division for the Union Pacific Railroad and Southern Pacific Railroad. In the early 1960s Union Pacific started asking for a 15,000 hp 3-unit locomotive set to replace the turbines...
and the ALCO Century 855
ALCO Century 855
The ALCO Century 855 was ALCO's most powerful diesel-electric locomotive and, at the time, the most powerful diesel locomotive ever built. Powered by a pair of 16 cylinder ALCO 251C diesel engines, and rated at , it was ALCO's answer to the EMD DD35 and the GE U50. The C855 rode on four two-axle...
.
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. 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.
Most were withdrawn from service in 1973 and 1974 and traded-in to GE for more modern high-powered units, although Southern Pacific's three survived in service until 1977.
The U50 is sometimes inaccurately referred to as the U50D, a back-formation from the U50C
GE U50C
The GE U50C was a 5,000 hp diesel locomotive built by GE Transportation Systems. They were twin-engined locomotives, combining two 2,500 hp diesel engines....
name given to the six-axle units. The name is incorrect and was never used by the manufacturer or the railroad. The U50 did not ride on D trucks in any case. It is also sometimes referred to as the U50B, but this is incorrect as well. Some references erroneously give the wheel arrangement as B-B+B-B.