The Union Pacific's gas-turbine-electric (GTEL) fleet was the 1950s and '60s manifestation of its ongoing love affair with massive, larger-than-life locomotives - a family line of giant power that began with the 9000-class 4-12-2 steamers, continued with the Challengers, Big Boys, and GTELs, and ended with the DDA40X Centennial diesels. In the postwar era, this stemmed from a belief that maintenance costs were more related to the number of engines on the roster than their size. By that logic, a smaller number of large locomotives would be cheaper to maintain than the fleets of multiple-unit diesels employed by every other Class 1 railroad. In addition, the UP loved to experiment - witness its early-1900s sponsorship of the McKeen car, a cross between a torpedo boat and a passenger car. In that context, the UP's ownership of the world's only significant fleet of gas turbines, essentially turbojet engines on wheels, seems only natural.
A gas-turbine-electric is basically a diesel engine with a large turbine replacing the diesel as the prime mover. In a turbine, intake air is compressed by spinning turbine blades and fed into combustion chambers, where fuel is added and ignited, as in a jet engine. The hot exhaust gases spin the blades of another turbine that powers one or more generators, which produce electricity to power diesel-type traction motors.
By the early 1960s, UP's GTEL fleet was having some success, with 4500 hp and 8500 hp units employed in fast freight service. Alco-GE, and later General Electric alone, had built all of them, combining expertise in locomotives and aircraft engines. Their turbine fuel was Bunker C oil, a cheap byproduct of petroleum distillation that was considered almost waste material at the time. But in 1962, a year after GE delivered the last 8500 hp engine, UP tried an experiment on its own, using pulverized coal as fuel.
Compared with the factory-new GE engines, coal turbine No. 80 was a Frankenstein creation, stitched together from the bodies of four locomotives. Up front and housing the control cab was a recycled Alco PA, arguably the most beautiful of first-generation diesels. In contrast with the oil-fueled GTELs, which had small diesel motors just for starting the turbine and moving it around an engine yard, the PA's 2000 hp prime mover contributed to No. 80's road power. Behind the PA was the turbine unit, built on the chassis of a Great Northern W-1 electric engine sold to the UP as scrap. The turbine itself, rated at 5000 hp, came from an older UP GTEL built in the early 1950s. Bringing up the rear was a centipede coal tender from a retired UP Challenger 4-6-6-4. Where the water tank had once resided, UP's shop crews installed a crusher to pulverize the coal and feed it to the turbine. The entire locomotive measured over 200' long, significantly more than anything else on the UP roster.
Unfortunately, the use of coal dust as a fuel magnified a problem that already haunted the GTEL fleet: metal erosion and soot on the turbine blades. After less than six years on the road, No. 80 was retired in 1968, having racked up less than 10,000 miles in service, compared with a million miles on average for the oil-fueled turbines. But while the prototype No. 80 was a failed experiment, our dependable Premier model - with four motors and three smoke units - lets you replicate the drama and majesty of what 200 feet of locomotive and 7000 horsepower could do.