Monday, May 4, 2026

UP GE/Alco gas-turbine-electric locomotive


The Union Pacific GTELs were a series of 55 gas-turbine–electric locomotives with a B+B-B+B confifuration [later (C-C)+(C-C)] built by Alco-GE and General Electric from 1952 to 1961 and operated by Union Pacific from 1952 to 1970.

Union Pacific operated the largest fleet of GTELs 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 and marketed by the Alco-GE partnership until 1953. The prototype was introduced in 1948 and was followed by three series of production locomotives. At one point, Union Pacific said the GTELs hauled more than 10% of the railroad's freight.

Fuel economy was poor, for the turbine consumed roughly twice as much fuel as an equally powerful diesel engine. This was initially not a problem, because Union Pacific's turbines burned Bunker C heavy fuel oil that was less expensive than diesel. But this highly viscous fuel is difficult to handle, with a room-temperature consistency similar to tar or molasses. To solve this problem, a heater was built into the fuel tanks (and later into fuel tenders) to heat the fuel to 200 °F (93 °C) before feeding it into the turbine. Eventually UP switched from Bunker C to modified No. 6 heavy fuel oil, which contained less pollutants and solvents.

Soot buildup and blade erosion caused by corrosive ash plagued all of the turbines. Changes to the air intake systems on the production turbine locomotives improved the quality of the air that reached the turbines, which in turn reduced the wear to the turbine blades and increased the turbine's running life. The GTELs were operated into late 1969 and the final two (numbers 18 and 26) were stored at the Cheyenne roundhouse in operating condition until being retired in February 1970. Both were later sent to museums.

No comments: