Union Pacific No. 80 (also known as the GTEL Coal Burner) was an experimental gas turbine-electric locomotive (GTEL) built by the Union Pacific Railroad (UP) themselves in October 1962. The UP's conventional GTELs were split into three generations that were built by ALCO-GE and General Electric (GE) between 1952 and 1961 and initially meant to replace their 4-8-8-4 "Big Boy" and 4-6-6-4 "Challenger" type steam locomotives. Being an experimental GTEL, instead of burning Bunker C fuel or compressed propane, the UP wanted to see if they could build a GTEL that burned coal. When it came time to build the coal turbine, it was basically cobbled together from a bunch of different things. The A unit was a modified ALCO PA-1 type diesel locomotive, the B unit was a modified Great Northern Railroad (GN) W-1 type electric locomotive, the turbine was borrowed from one of the UP's older conventionally-powered first or second-generation GTELs, and the coal tender was a rebuild from UP 4-6-6-4 type steam locomotive No. 3990.
This experimental GTEL had a total of 25 axles from stem to stern, both powered units had eighteen axles, twelve of which were powered, the PA-1 unit's 2,000 horsepower diesel engine was retained, and the B unit carried the main power plant for the main generators, which added another 5,000 horsepower, making a combined total power output of 7,000 horsepower. It also had a total length of 226 ft., making it the longest locomotive ever built. It originally had a road number of 80, but in 1965, it was renumbered to 8080 to avoid conflict with the then-new EMD DD35 type diesel locomotives that were being introduced at the time. Ultimately, and unfortunately, it was plagued with problems from the get-go, as blade erosion and soot buildup issues encountered in earlier GTELs were magnified with the coal turbine and grinding up the coal into particles fine enough to avoid damage to the turbine blades proved burdensome.
Because of all of these problems, it was eventually declared a failure and later scrapped after only spending twenty months in service. While the UP's conventional GTELs racked up more than 1,000,000 miles in revenue service, the coal turbine only ran less than 10,000 miles before being officially retired from service on March 15, 1968. Most of the UP's conventional GTELs were also scrapped after retirement, but fortunately, two of the third-generation GTELs (Nos. 18 and 26) have been preserved. No. 18 is on static display at the Illinois Railway Museum in Union, IL and No. 26 is on static display at Union Station in Ogden, UT.