Steam Locomotive Fans

Big Boy #4012 on display at Steam Town. Photo courtesy of Richard Higgsy

The Union Pacific Big Boys were the ultimate steam locomotives. One could simply not build anything larger. They were the biggest succesful reciprocating steam locomotives in the world. With their 4-8-8-4 wheel arangement, they were absolutely ENORMOUS. Only a few Steam Turbines were longer, and PRR's S1 class 6-4-4-6 duplex was longer by about 6 feet. But none of these locomotives were succesful, so the Big Boy reigns supreme in everything, except weight. The C&O's monster 2-6-6-6s Alleghenys were heavier by a few thousand pounds. But typically Big Boy's are called the biggest steam locomotives.

The first of UP's 4-8-8-4s were built in ALCO's Schenectady, (excuse my spelling, that is one difficult word!) New York plant in 1941. #4000, the first of the Big Boys, was delivered in the fall of 1941. Numbers 4001 through 4019 follwed. The first Big Boys were built with the after coolers on the pilot deck. These were later moved behind a protective door on the front of the pilot. The later group of Big Boys were built to this design.

In 1944, the UP ordered 5 additional 4-8-8-4s to help with the war time traffic. These were numbers 4020 to 4024, and were much heavier than the earliar Big Boys, due to war time restrictions on steal. Otherwise these were no different than the first group of Big Boys.

4022 fresh out of the ALCO shops in 1944. Courtesy Lupo Mulder

The Big Boys could develop hundreds of thousands of pounds of tractive effort, enough to pull a 5 1/2 mile long train on level track. They could run up to 80 mph, but they achieved maximum efficency in the 30-45 mph range. They were the best steam locomotives to work on on the Union Pacific, according to many UP crews. They were very easy to fire, and rode incredibly smooth. An engineer knew they had a powerhouse underneath them when at the throttle of a Big Boy.

All the Big Boys burned coal, and the had massive 100 square foot fire boxes to do so. In 1946, with the costs of coal rising, #4005 was briefly converted to burn oil. The project would have been succesful, but they only used 1 burner, causing the fire box to burn unevenly. 2 or 3 burners probably would have worked. The cost o coal went down again in 1947, and #4005 was converted back to burning coal.

Many people don't know that UP officials were origonally going to call the Big Boys the "Wasatch Type", after the tough grades they would face. However, as #4000 rolled out of ALCO, a worker chalked "Big Boy" on the smoke box. It summed up the locomotives nicely, and the name stuck.

Though the Big Boys could produce a monsterous 6,500 horse power and higher, and could muscle heavy trains over the mountains at 40 to 80 mph, they eventually were replaced by diesels. The last Big Boy ran in July of 1959, and all were retired by 1962. The diesels reduced maitanance costs and better availabilty was what doomed all steam locomotives.

8 Big Boys are presserved across the U.S. The best presserved Big Boy is the 4014 at the Los Angeles County Fair Grounds. It seems that all you'd need to do is give it a load of coal and water and take off down the mainline. It's been preserved that well!

Modeling Tips: Athearn Genesis has announced HO scale Big Boys with sound, #'s 4005 and 4006. Monogram and Revell make a plastic, non running Big Boy HO kit. Boswer produces a metal HO powered Big Boy kit. Rivarossi has made HO scale Big Boy models. Trix makes an HO scale Big Boy with sound. MTH and Lionel make one in O. Several manufactuers have made Big Boys in most scales in Brass.