The "Big Boy"

ID # 1,109

THE "BIG BOY"

The world's longest and heaviest single-unit locomotives, the giant articulated 4-8-8-4 "Big Boys," were built for the Union Pacific Railroad by the American Locomotive Company. Each weighed 1,200,000 pounds in working order with her tender. This example, No. 40I9, was nearly 86 feet long 132 feet with tender. These power factories were designed to pull heavy fast freight Over the Wasatch Mountains without the use of helper engines. Because of their great length and power, they worked mostly in the mountainous area of the West, and used extra-long turntables. According to Union Pacific motive power experts they could make up to 80 miles per hour, but developed their top horsepower at 30 miles per hour. Nearly all of the Big Boys have been scrapped. One of them is on exhibition at the National Museum of Transport, St. Louis, Missouri.

UNION PACIFIC RAILROAD