Union Pacific 844 is a 4-8-4

4-8-4

Under the Whyte notation classification of steam locomotives, 4-8-4 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and four trailing wheels on two axles .Other equivalent classifications are:UIC classification: 2D2...

 steam locomotive

Steam locomotive

A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

 owned by 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....

. It was the last steam locomotive delivered (in 1944) to Union Pacific and is unique in that it is the only steam locomotive never retired by a North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

n Class I railroad

Class I railroad

A Class I railroad in the United States and Mexico, or a Class I rail carrier in Canada, is a large freight railroad company, as classified based on operating revenue.Smaller railroads are classified as Class II and Class III...

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Union Pacific 844 was one of 10 locomotives that were ordered by Union Pacific in 1944 and were designated as class FEF-3

Union Pacific FEF Series

The FEF was a series of three types of 4-8-4 steam locomotives owned and operated by the Union Pacific Railway. The classes were: FEF-1; FEF-2; FEF-3. "FEF" was an acronym for the wheel arrangement, "four-eight-four."-Origins:...

. The FEF-3 class was similar to the earlier FEF-2 class as both were designed as passenger engines and pulled such trains as the Overland Limited, Los Angeles Limited

Los Angeles Limited

The Los Angeles Limited was a named passenger train in the United States. It was operated by the Union Pacific Railroad from 1905 to 1954.- History :...

, Portland Rose and Challenger

Challenger (passenger train)

The Challenger was a named passenger train fleet jointly operated by the Union Pacific Railroad and the Chicago and North Western Railway . The economy service ran between Chicago, Illinois and several major cities located along the West Coast of the United States...

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