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Union Pacific Big Boy

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The American Locomotive Company (ALCO) 4000 Class, better known as the Union Pacific Big Boy, is a 4-8-8-4 simple articulated type of steam locomotive built by the American Locomotive Company (ALCO) specially for the Union Pacific Railroad (UP) between 1941 and 1944. They are the most iconic and best-known steam locomotives on the Union Pacific. Of the twenty five Big Boys that were built, eight of them survive in preservation today, those being Nos. 4004, 4005, 4006, 4012, 4014, 4017, 4018, and 4023. Today, No. 4014 is the only surviving Big Boy in operating condition, as well as the only Big Boy to ever operate in excursion service.

The Controls for the Union Pacific Big Boy

The Controls for the Union Pacific Big Boy

History[]

During World War II in the 1940s, railroads in the United States were in dire need of larger steam locomotives to deliver long and heavy trains (which became longer and heavier due to the stock market boom as a result of the US recovering from the Great Depression; aside from having more materials needed to built vehicles and weapons to supply troops in combat), to whom the economy skyrocketed after the Great Depression, and many companies relied on trains to deliver their goods.

Hence, railroads like the Union Pacific needing larger locomotives to haul such long and heavy freight trains through their long routes. Which meant the request from ALCO to design a much larger version of their "Challenger" type of 4-6-6-4 articulated steam locomotive for conventional horsepower.

The 4000 Class dominated the steam locomotive market by having less wheels and more power and length compared to other Mallet types of steam locomotives (such as the "Erie Triplex" Class from the Erie Railroad), which meant that they were easier to maintain, yet they were very expensive to operate because of how much water and coal they consumed, as well as how much time, effort, and money used to mold the metal and other materials for the steaming giants (yet, more purchases led to ALCO's large earnings).

Once they were purchased by the Union Pacific; and when they were still in production, most railfans, train enthusiasts, locomotive builders, and railroad employees nicknamed the giant type of steam locomotive the "Big Boy". (yet the name; however, was rumored to have began as a simple nickname stenciled in the boiler of an ALCO employee during the construction of the first one built in early-1941). But their times hauling trains on the Union Pacific system unfortunately came to an end during the 1950s, when the GE GTEL Gas Electric Turbine super-powered diesel turbine locomotives began to replace the Big Boys and Challengers during the end of the Steam Era, however in their last few years, they were put onto reserve service until their official decommission in 1962. Seventeen engines succumbed to the cutter's torch; surprisingly - for such a small number built - eight of the 25 beasts built survive, all which are currently on static display in various museums throughout America, except for 4014, which has been restored to operating condition.

Accidents and incidents[]

On April 27, 1953, No. 4005 was hauling a freight train consisting of 62 cars eastbound near Red Desert, Wyoming, west of Medicine Bow. While traveling at approximately 50 miles per hour, the locomotive derailed on a misaligned switch. The Big Boy tipped onto its left side, dragging the tender and the first 18 freight cars off the tracks. The wreck destroyed a significant stretch of rail and equipment in the train consist. Several cars were destroyed, and the wreckage blocked the line for many hours. The wreck killed the engineer and fireman in the cab, along with a brakeman riding in the locomotive.

On May 16, 2019, as No. 4014 entered the Rawlins yard at slow speed, the second engine’s driver axles Nos. 2 and 3 derailed, dropping into the gauge while the rest of the locomotive remained on the rails. The UP steam crew, along with local track forces, swiftly repaired the track under the derailed wheels. They used wood blocking to “walk” the drivers back onto the rails Trains. The derailment occurred around 2:15 p.m., and the locomotive was fully reranged and back on track by about 5:20 p.m, resuming movement shortly after TrainsLaramie Live. The derailment was low-speed and did not cause injuries or major damage. The excursion continued with only a minor delay.

Locomotive Roster[]

Road number Built date Serial number First run date Retirement date Disposal date Status Notes
4000 August 1941 69571 - September 1961 November 1961 Scrapped -
4001 September 1941 69572 - November 1961 November 1961 Scrapped -
4002 September 1941 69573 - November 1961 February 1962 Scrapped -
4003 September 1941 69574 - February 1963 May 1963 Scrapped -
4004 September 1941 69575 - June 1963 - Preserved This Big Boy received a cosmetic restoration was completed in 2018,
4005 September 1941 69576 - July 1962 - Preserved -
4006 September 1941 69577 - May 1961 - Preserved -
4007 September 1941 69578 - August 1961 October 1961 Scrapped -
4008 September 1941 69579 - January 1962 August 1962 Scrapped -
4009 September 1941 69580 - July 1962 May 1963 Scrapped -
4010 September 1941 69581 - July 1962 May 1963 Scrapped -
4011 October 1941 69581 - July 1962 June 1963 Scrapped -
4012 October 1941 69583 - February 1962 - Preserved -
4013 November 1941 69584 - July 1962 April 1962 Scrapped -
4014 November 1941 69585 - June 1961 - Operational -
4015 November 1941 69586 - August 1961 September 1961 Scrapped -
4016 November 1941 69587 - January 1962 March 1962 Scrapped -
4017 December 1941 69588 - May 1961 - Preserved -
4018 December 1941 69589 - July 1962 - Preserved -
4019 December 1941 69590 - January 1962 February 1962 Scrapped -
4020 November 1944 69777 - July 1962 May 1963 Scrapped -
4021 November 1944 69778 - January 1962 August 1962 Scrapped -
4022 November 1944 69779 - February 1962 August 1962 Scrapped -
4023 November 1944 72780 - July 1962 - Preserved -
4024 November 1944 69781 - July 1962 October 1962 Scrapped -
Number 4012 at the in Scranton, Pennsylvania.

Number 4012 at the Steamtown National Historic Site in Scranton, Pennsylvania.

Trivia[]

  • Apparently, the original name of the Big Boy was supposed to be "Wasatch". However, as the story goes, an unknown worker at ALCO chalked "Big Boy" on the boiler of No. 4000, unintentionally christening it with the name these locomotives go by.
  • The Big Boy has more steam valve controls than any other type of steam locomotive.
  • Most average people and train enthusiasts often confuse the Challenger and Big Boy for one another. The main differences are the position of the boiler number plate, and the wheel arrangements.
  • Big Boys were rarely occasionally assigned to passenger service.
  • Most crew members who drove Big Boys often used auger drills to drill the coal stored in the tender because of how long it often sat due to the size of the tender. Hence, coal being refilled every month or so.
  • The Japanese anime TV series "Galaxy Railways" features a space train named Big One, a very stylized depiction of a Big Boy.
  • The Big Boys' smokestack were actually two smokestacks combined and covered with smoke deflectors.
  • Only two Big Boys have ever been converted from burning coal to burning oil, those being No. 4005 and 4014. No. 4005 was converted to burn oil in December 1946 as part of an experiment due to a coal strike, but the conversion wasn't that much of a success and it was soon after converted back to burn coal in March 1948. No. 4014 was converted to burn oil during its restoration to operating condition for excursion service, which was completed in May 2019, just in time for the 150th anniversary of the Driving of the Golden Spike in Promontory Summit, Utah.

Videos[]

Gallery[]

List of Union Pacific Big Boy Locomotives
Real-Life Members: 4000 • 4001 • 4002 • 4003 • 4004 • 4005 • 4006 • 4007 • 4008 • 4009 • 4010 • 4011 • 4012 • 4013 • 4014 • 4015 • 4016 • 4017 • 4018 • 4019 • 4020 • 4021 • 4022 • 4023 • 4024
Fallen: 4000 • 4001 • 4002 • 4003 • 4007 • 4008 • 4009 • 4010 • 4011 • 4013 • 4013 • 4015 • 4016 • 4019 • 4020 • 4021 • 4022 • 4024
Preserved: 4004 • 4005 • 4006 • 4012 • 4014 • 4017 • 4018 • 4023
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