The History of the Big Boy Locomotive, Part 1

Posted by John E. Bush
on Thursday, May 10, 2018

Please let me open by stating that I am humbled and excited by the invitation to prepare and share this blog. The chance to do this now, as we anxiously await completion of the restoration to operation of Union Pacific Big Boy No. 4014, a concept only dreamed of just a few short years ago, somehow brings a feeling of kinship. As if I’m somehow a part of the family so diligently working toward what was for decades a seemingly impossible, never-to-happen goal. I hope it proves half as much fun for you as it will be for me.

Big Boy No. 4014 in November 2013, when it was extracted from the railroad museum at the Los Angeles County Fairgrounds.

I was asked to write a little about the history of Union Pacific’s 25 4-8-8-4 locomotives and at the same endeavor to bring something new to those who in the past may not have taken a really close look at these un-paralleled giants. While it’s natural that 4014 is the center of what’s happening at present, with each blog entry my effort will be toward bringing forward a few historic tidbits about these great engines as well as try to point out a thing or two most may not have previously known about them.

I think it makes some sense to start at the beginning. First, it needs to be understood that while the operating headquarters of the railroad was located in Omaha, Neb., the Union Pacific Railroad Co., a Utah corporation, was headquartered and operated from 120 Broadway St. in New York City. Speaking personally, it wasn’t until I had become involved in some other research projects that I was made truly aware of the extent to which New York exerted control over operations of the railroad, not surprisingly in particular the financial matters. I will try to bring this point into better focus shortly.

It is generally well known and accepted that by the middle of the 1930s decade the United States began to find itself becoming one of the major industrial suppliers to a world deeply engulfed in military conflicts. The nation was still in the depths of the great depression. When combined with government-backed projects intended to improve matters across the nation and at the same time provide jobs to thousands, some of whom had been without work for half a decade and more, these global needs caused America to begin to get back to work as demand grew for all sorts of products.

The railroads were immediately affected by these matters and from 1935 the builders of locomotives and rolling stock, which had received perilously few orders for new equipment the preceding several years, found themselves recalling furloughed employees as orders for new cars and locomotives grew.

The Union Pacific had long suffered a major operating bottleneck, the famous Wahsatch grade which forced the breaking up of eastbound trains traversing the 175.6 miles from Ogden, Utah to Green River, Wyo. As traffic levels increased, an effort aimed at dealing with this growing problem was launched. Mechanical engineers at Union Pacific worked with counterparts at the American Locomotive Co. Together they came up with a new type of locomotive, a simple-expansion articulated capable of moving approximately the same tonnage as the 88 locomotives of the famous 4-12-2 class but at higher speed and at less cost (the 3-cylinder engines of the 4-12-2 design had in their own time accomplished basically the same thing, replacing compound-expansion 2-8-8-0s in all but the most steeply-graded regions). These engines were the first of the 4-6-6-4 type and Union Pacific named them “Challengers.” Commencing with the 1936 delivery of the first of these engines, numbered in the 3900 series, a total of 40 4-6-6-4s were received by the end of 1939. Their arrival allowed the railroad to release other power for assignments in different areas and initially reduce the need for helper service.

The officers and board of directors in New York were always interested in reducing expenditures and were initially delighted with the new locomotives. However, as the pace of traffic continued to grow it was very soon found that if the tonnage was to be moved and the railroad kept in efficient operation double-heading was required with the Challengers just as it had been during periods of heavy traffic with the other classes in the past. Naturally, double-heading resulted in more crews being paid, and more locomotives to fuel, water and maintain. While the Challengers allowed freight to be moved more quickly, the railroad found itself virtually where it had been when first purchasing the 4-6-6-4s. Even prior to delivery of the last of the Challengers in 1939 it was decided in Omaha that the time had come to revisit the Wahsatch bottleneck.

This blog is Part 1 of 2. Stay tuned for Part 2 next week.

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