Union Pacific’s Big Boy No. 4014 can now operate on its own, without a diesel locomotive in tow.
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The legendary locomotive was recently outfitted with an updated Positive Train Control (PTC) system, a system designed to stop certain rail incidents before they occur. The new system’s components – computer, GPS satellite and radio antennas – are now entirely housed within Big Boy and its tender. This equipment used to be mounted and connected by hard wire to an accompanying diesel locomotive.
The system has been tested and is ready for use on Big Boy’s upcoming 2024 Westward Bound Tour from Wyoming to California.
“We are still going to travel with a diesel locomotive most of the time – saving wear and tear on Big Boy’s brakes and extending fuel and water, when needed – but this is going to give our Steam team greater flexibility to park the locomotive, switch the train or operate Big Boy solely as needed,” said Ed Dickens, manager-Heritage Operations and Big Boy locomotive engineer.
Big Boy will embark on a four-week tour across five western U.S. states, starting June 30. It will pass through Wyoming, Utah, Nevada, California and a short stretch of southeast Idaho.
In 2021, Big Boy was outfitted with its first PTC unit, including a Cab Display Unit (CDU) mounted in the cab. The interactive screen is used by Big Boy’s locomotive engineer and conductor to monitor speed, confirm authority to operate on the track and show a route’s grade profile, among other things.
The CDU will remain in its present position, but the new system’s computer and other key components are now mounted in the tender. The tender rides behind Big Boy and carries the fuel supply and water used to operate the steam engine. The oil is burned in Big Boy’s firebox, heating the water and creating the steam that powers the locomotive.
“This new system has already made my life and the Steam team’s lives simpler, making it easier to plan and execute trips,” said Dickens. “We can now easily uncouple Big Boy from the diesel engine without worrying about moving hard wires.”