A review of Athearn Big Boy
Background:
They are often proclaimed as the largest steam locomotives ever built, but that title is quite controversial — there were heavier locomotives, and possibly more powerful locomotives. However, without tender, the Big Boy's locomotive body was the longest of all of them and fully loaded with water and fuel the Big Boy was the heaviest of all of them, even though the locomotive without tender was lighter than some. The Big Boys were the only locomotives to have the 4-8-8-4 wheel arrangement in the Whyte notation — in other words, combining two sets of eight driving wheels with both a four-wheel leading truck for stability at speed and a four-wheel trailing truck to support a large firebox. The locomotive's wheel arrangement makes it clear that it was designed for power at speed. The Big Boy locomotives were created by the Union Pacific's need for a locomotive that could pull a 3600 short ton (3300 metric ton) freight train over the long 1.14% grade of the Wasatch. Helpers were needed for this grade at the time. Adding and removing helpers from a train, crewing them, etc. slowed down the movement of trains. For such a locomotive to be worthwhile, it had to be more than just a slow mountain lugger; to avoid locomotive changes, the new class would have to be able to pull that long train at speed — 60 mph (100 km/h) — once past the mountain grades. In fact, the Big Boys were designed to be stable at 80 mph (130 km/h), so they were built with a heavy margin of safety. Few previous articulated locomotives were capable of such speed; UP's earlier Challenger 4-6-6-4s were, however, and in many respects the Big Boy could be regarded as a longer, heavier and more powerful Challenger. Twenty-five of them were built, split into two groups of 20 and 5 locomotives. All were coal burning, with large grates to burn the Union Pacific's low quality Wyoming coal. One locomotive, #4005, was converted to oil burning, but unlike the experiences on the smaller Challengers, oil burning was not successful. The locomotive soon reverted to the standard (coal burning) configuration. The often cited reason for the unsuccessful oil-fired test was the use of a single burner which, with the Big Boy's larger firebox, created a very unsatisfactory and uneven heating. It remains unexplained why multiple burners were not used. The Big Boys did sterling service in the Second World War, especially since they proved so easy to fire that even a novice could do a fair job. Since many men who were unsuited to combat service were instead drafted into the railroads to replace crewmen who had joined up, this proved highly advantageous. During the war, after German agents filed reports that the Americans had giant steam engines that were moving huge trains full of vital war material over steep mountain grades at high speed, their reports were dismissed as "impossible" Like all steam locomotives, postwar increases in the price of both coal and labor meant that the writing was on the wall for the Big Boys, but even so they were among the last steam locomotives taken out of service. The last service train hauled by a Big Boy was in July 1959, the last run ending early in the morning of July 21st; most were stored operational until 1961, and four remained in operational condition at Green River, Wyoming until 1962.
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Locomotive:
Type - Steam Locomotive |
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On The Track:
SSP Klamath Block 1.7%, 36" Radius Ruling Grade Pulling Capacity (40' free rolling cars) - 25 cars |
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DCC System:
DCC Ready - Yes |
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Apperance:
Painting Quality: Excellent |
Overall:
Price / Value: Miscellaneous Final Comments: Great loco, poor sound and cannot pull a 50 cars up a 1.7% grade which the real Big Boys could do is a disappointment. Union Pacific Big Boy. (2007, February 6). In Wikipedia, The Free Encyclopedia. Retrieved 02:41, February 7, 2007, from http://en.wikipedia.org/w/index.php?title=Union_Pacific_Big_Boy&oldid=106087901
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