20-30147-1 UNION PACIFIC BIG BOY WITH COAL TENDER #4017-O QuickBooks and 4 dynamos plus cylinder

and 4 dynamos plus cylinder cocks

Prototypes seen from coast-to-coast 1971 to the present

enduring “real life” testing

3 1/2" L x 1 1/8" W x 5/8" H

finely engineered precision track

20-30147-1 UNION PACIFIC BIG BOY WITH COAL TENDER #4017-O QuickBooks and 4 dynamos plus cylinderJust 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 &