Just months before Pearl Harbor, the American Locomotive Company delivered the first Big Boy to the Union Pacific Railroad. The UP's Department of Research and Mechanical Standards had designed the locomotive for a specific task: to pull a 3600-ton train unassisted over the Wasatch Mountains in Utah. While the Big Boy is often cited as the biggest steam locomotive ever built, in fact it is not. The Norfolk & Western's Y6 and A, the Duluth Missabe & Iron Range's Yellowstones, and the Chesapeake and Ohio's Alleghenys were all in the same league, and some exceeded the Big Boy's weight and power. _But in the battle for hearts and minds, the Big Boy won.
Model features die cast boiler, tender body and metal chassis, RP-25 metal wheels on metal axles, operating lights, detailed cab interior, 5-pole precision skewed flywheel equipped motor, metal details, real coal load, synchronized puffing ProtoSmoker system and Kadee compatible scale couplers.