Big Boy story began in 1940

The world's largest steam locomotives received an accidental nickname
4021 Sherman Hill Kindig June 1949
No. 4014 climbing Wyoming's Sherman Hill, behind helper No. 4021, on June 25, 1949.
R.H. Kindig
When Union Pacific 4-8-8-4 Big Boy No. 4014 takes to the rails again following restoration by Union Pacific, admirers of the huge machine would do well to remember two names: Otto Jabelmann and William Jeffers. It was Jeffers who, as president of Union Pacific in 1940, told Jabelmann’s Research and Mechanical Standards Department to design and construct larger motive power to conquer the grades not of famed Sherman Hill in Wyoming, but the Wahsatch Mountains east of Ogden, Utah.

While the majority of UP’s Overland Route from Omaha to the Southern Pacific interchange in Ogden was relatively grade free, the Wahsatch Mountains were a significant barrier, with eastbound 1.14 percent grades from Ogden to Wahsatch, Utah. Since the opening of the transcontinental railroad in 1869, UP designed larger and larger steam power to conquer the Wahsatch range. The Big Boy would be the culmination of those designs.

According to the seminal book “Big Boy” by the late William W. Kratville, the Research and Mechanical Standards Department was established in 1936 under Vice President Jabelmann. Jeffers order to Jabelmann was to develop a locomotive capable of pulling 3,600 tons over the Wahsatch unassisted. To do so, Kratville recounts, the locomotive would have to have 135,000 pounds of tractive effort and an adhesion factor of four. Engineers concluded to meet Jeffers demands would require an eight-wheeled articulated with four wheel lead and trailing trucks – thus the 4-8-8-4-wheel arrangement was born.

Within three months a design team was assembled with the builder, the American Locomotive Company, with UP furnishing members of the Research and Mechanical Standards Department to assist. Because UP had accumulated a great deal of research data, the entire project only took about one year to complete: six months to design, fabricate and acquire parts, and another six months to build the first locomotive.

Union Pacific initially ordered 20 Big Boys from Alco at a cost of $265,174 each. The engines were deliberately overdesigned. For example, they were built to run at speeds up to 80 mph, although they would never be moving freight at that speed. This was done to ensure that rotating parts, such as the rods, would not break in daily service.

While the new engines were being built, UP prepared for them. Bridges had to be rebuilt to handle their weight, curves realigned, and new 135-foot turntables installed at servicing points. Heavier 130-pound rail was laid between Ogden and the Wahsatch summit. While the normal Big Boy haunt would be between Ogden and Evanston, Wyo., as World War II progressed, the Big Boys’ operational territory was extended east from Evanston to Green River, Rawlins, Laramie, and Cheyenne. They were also cleared to operate between Salt Lake City and Pocatello, Idaho, and Salt Lake City and Los Angeles, although they likely never did.

Naming the new locomotive came by accident. While under construction, an Alco machinist chalked the name “Big Boy” on the smokebox of the first engine, No. 4000. The name stuck, although it was rumored that UP had considered naming the class “Wahsatch.” The Big Boys were 132 feet long, roller bearing equipped, and weighed 1.2 million pounds.

No. 4000 was shipped dead via the Delaware & Hudson, New York Central, and Chicago & North Western to Council Bluffs, Iowa. A UP switch engine towed the engine across the Missouri River to Omaha Shops where it was officially accepted on Sept. 5, 1941. Later that month, No. 4000 was steamed up for the first time, and then put on display at Omaha Union Station. It traveled light to Council Bluffs for servicing, then back to Omaha to pick up a train of 100 empty Pacific Fruit Express reefers. The locomotive made several stops as it traveled west across Nebraska for water, fuel and crews, arriving in Cheyenne early the following day.

No. 4014, along with Big Boys’ 4004 and 4016, was involved in a test against a three-unit diesel in April 1943 between Ogden and Evanston, Wyo. According to Kratville, on April 2, 1943, No. 4014 took 65 cars and 3,479 tons out of Ogden. All the way upgrade the throttle was open less than full, and yet No. 4014 accelerated at points on the grade from 1.8 to 4.5 mph per minute. A top speed of 42 mph was recorded on level track, while the minimum speed was 13 mph on a three-degree curve on a 1.14 percent grade. Following tests with the other two Big Boys and the diesels, the internal combustion power proved to do no better than the steam engines had, and the railroad concluded that steam would remain on the route.

As World War II raged in 1944, UP received authority from the War Production Board to build five more Big Boys, Nos. 4020-4024. They were identical to the other locomotives except for the use of heavier metals in the boilers and rods. One member of this class, No. 4023, survives on display in Omaha.

The last Big Boys operated on July 21, 1959. Most were stored operational until 1961. Unfortunately the first Big Boy, No. 4000, was scrapped in Cheyenne in August 1961, but eight other Big Boys escaped No. 4000’s fate – almost one third of the fleet. No. 4014 was retired in December 1961 after 1,031,205 miles, and was presented to the Southern California Chapter of The Railway and Locomotive Historical Society. Since 1962 it has been displayed by the society in Pomona, Calif., but now will see new life, extending the Big Boy story begun by Jeffers and Jabelmann well into the 21st century.
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