Power type Steam Build date November 1941 | Serial number 69583 Fuel type Coal | |
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Builder American Locomotive Company Gauge 4 ft 8 ⁄2 in (1,435 mm) | ||
Union Pacific 4012 is one of the world's largest steam locomotives and is one of eight preserved Union Pacific Big Boy locomotives. Built by American Locomotive Company in November 1941, Big Boy 4012 was retired in 1962 and can be viewed at Steamtown National Historic Site in Scranton, Pennsylvania.
History
Union Pacific 4012, nicknamed "Big Boy", is a 4-8-8-4 type locomotive built by American Locomotive Company in November 1941. It is among the world's largest steam locomotives. One of 25 built, No. 4012 is one of eight of its type to survive the advent of the diesel era. Referred to as an "articulated" locomotive, because it has more than one set of drivers, Big Boy weighs 1,250,000 pounds (570,000 kg). This locomotive worked for 21 years hauling freight between Cheyenne, Wyoming, and Ogden, Utah, logging over 1,000,000 miles (1,600,000 km) before its retirement in 1962.
4012 was originally on display at Steamtown, U.S.A in Bellows Falls, Vermont, until 1984 when Steamtown USA moved to Scranton, Pennsylvania. Since the Steamtown turntable and roundhouse are too small to accommodate the size and weight of 4012, it has remained out-of-doors since its arrival at Scranton.
The Steamtown Special History Study recommended that this locomotive remain at Steamtown because it is the only articulated locomotive in the Steamtown USA collection and recommended that due to its good condition, 4012 could be restored to working order. However, the study also recommended that 4012 remain on static display, because it is doubtful that the "track, switches, culverts, trestles, bridges, wyes, turntables, and other facilities that would have to carry her [could] bear her great weight".