Internal Combustion Locomotives
Union Pacific 18
|Description:||D-E Turbine A Unit 8500 GTEL|
Union Pacific 18 is an example of the most powerful locomotive ever built in America. Rated at 10,000hp, it consists of the cab unit; the main power unit containing a turbine engine, similar to a jet engine, numbered 18B; and a tender to carry fuel for the turbine. The railroad designed these locomotives specifically to pull freight trains between Omaha, Nebraska and Ogden, Utah and 18 is one of only two in preservation. Their poor fuel economy and high maintenance costs of the turbine led to their retirement in the late 1960s.
Click here to see the listing for 18B, the main power unit for the turbine.
Click here to see the listing for the turbine’s tender.
Union Pacific 18 Details
Builder: General Electric
Year Built: 1960
Model: 8500 GTEL
Length: 165ft 11in
Weight: 849248 lbs
Brakes: 26L (Loco) / AB (Fuel Tender)
Engine: Cooper-Bessemer (A unit) / Gas-Turbine (B unit)
Motors: 12 GE 752E4
Description: A-unit with gas-electric hostler engine
Condition: Incomplete / cosmetically restored / not operational
This giant three-unit gas-electric turbine is the most powerful locomotive that ever saw service in the United States. It is one of 30 locomotives of this type and had 8,500 horsepower, more than four times as powerful as typical diesel-electric locomotives of the time and nearly twice as powerful as today’s high-horsepower diesels.
It was the 1930s when railroads began looking at turbine-driven locomotives as a way to increase fuel economy. Turbines used at power plants were very efficient, but finding a way to mount a turbine on a locomotive proved problematic. General Electric built a turbine locomotive for the Union Pacific Railroad (UP) in 1939 but its complexity made it unreliable and it was deemed a failure. After World War II, the UP revisited the idea. It asked General Electric to build on its experience designing gas turbine airplane engines and construct a gas-powered turbine locomotive.
A prototype built in 1948 was judged successful, so three orders of gas turbines were built between 1952 and 1961. These culminated in the three-unit, 8,500hp locomotives like UP 18. The turbines were essentially jet engines on rails, and when in operation they sounded like jet airliners. They used fuel at a prodigious rate, though the poor grade of oil that they burned helped offset the cost somewhat. They also used nearly as much fuel at idle as at full throttle, meaning that the railroad had to keep them in constant use while fired up.
Over time, as oil prices climbed and reliability problems increased, the turbines fell out of favor with the UP. The railroad ended up retiring them all by 1970, and sold nearly all for scrap. UP 18 is one of only two turbine locomotives from the Union Pacific still in existence. It retains its turbine engine but was stripped of many other components before acquisition by the museum.