Union Pacific Big Boy class locomotives
E493346
The Union Pacific Big Boy class locomotives were massive 4-8-8-4 articulated steam engines built for Union Pacific Railroad, famed as some of the largest and most powerful steam locomotives ever constructed.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Union Pacific Big Boy No. 4012 | 1 |
| Union Pacific Big Boy class locomotives canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T5116884 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Union Pacific Big Boy class locomotives Context triple: [Baldwin Locomotive Works, notableWork, Union Pacific Big Boy class locomotives]
-
A.
Union Pacific Heritage Fleet
The Union Pacific Heritage Fleet is a collection of restored historic passenger cars and locomotives maintained by Union Pacific Railroad for special excursions, public relations, and preservation of the company’s railroading legacy.
-
B.
Union Pacific Challenger
The Union Pacific Challenger was a named passenger train operated by the Union Pacific Railroad, known for providing comfortable, mid-priced long-distance service across the western United States.
-
C.
Atchison Topeka and Santa Fe 4-8-4 locomotive
The Atchison, Topeka and Santa Fe 4-8-4 locomotive is a powerful steam engine from the famed Santa Fe Railway, known for hauling high-speed passenger and heavy freight trains across the American West in the mid-20th century.
-
D.
Union Pacific dome cars
Union Pacific dome cars were distinctive passenger railcars featuring elevated glass-enclosed viewing domes that offered panoramic scenery on Union Pacific’s long-distance trains.
-
E.
Union Pacific No. 119
Union Pacific No. 119 was the steam locomotive that represented the Union Pacific Railroad at the 1869 Golden Spike ceremony marking the completion of the First Transcontinental Railroad.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Union Pacific Big Boy class locomotives Target entity description: The Union Pacific Big Boy class locomotives were massive 4-8-8-4 articulated steam engines built for Union Pacific Railroad, famed as some of the largest and most powerful steam locomotives ever constructed.
-
A.
Union Pacific Heritage Fleet
The Union Pacific Heritage Fleet is a collection of restored historic passenger cars and locomotives maintained by Union Pacific Railroad for special excursions, public relations, and preservation of the company’s railroading legacy.
-
B.
Union Pacific Challenger
The Union Pacific Challenger was a named passenger train operated by the Union Pacific Railroad, known for providing comfortable, mid-priced long-distance service across the western United States.
-
C.
Atchison Topeka and Santa Fe 4-8-4 locomotive
The Atchison, Topeka and Santa Fe 4-8-4 locomotive is a powerful steam engine from the famed Santa Fe Railway, known for hauling high-speed passenger and heavy freight trains across the American West in the mid-20th century.
-
D.
Union Pacific dome cars
Union Pacific dome cars were distinctive passenger railcars featuring elevated glass-enclosed viewing domes that offered panoramic scenery on Union Pacific’s long-distance trains.
-
E.
Union Pacific No. 119
Union Pacific No. 119 was the steam locomotive that represented the Union Pacific Railroad at the 1869 Golden Spike ceremony marking the completion of the First Transcontinental Railroad.
- F. None of above. chosen
Statements (59)
| Predicate | Object |
|---|---|
| instanceOf |
articulated locomotive class
ⓘ
steam locomotive class ⓘ |
| 4014RestorationCompletionYear | 2019 ⓘ |
| boilerPressure | 300 psi ⓘ |
| builder |
ALCO Schenectady Works
NERFINISHED
ⓘ
American Locomotive Company NERFINISHED ⓘ |
| classDesignation | UP class 4000 NERFINISHED ⓘ |
| configurationType | Whyte notation 4-8-8-4 ⓘ |
| countryOfOrigin |
United States of America
ⓘ
surface form:
United States
|
| cylinderArrangement | simple articulated ⓘ |
| cylinderCount | 4 ⓘ |
| cylinderSize | 23.75 in × 32 in ⓘ |
| designedFor |
long, heavy freight trains
ⓘ
steep grades ⓘ |
| designer |
Otto Jabelmann
NERFINISHED
ⓘ
Union Pacific Railroad mechanical department NERFINISHED ⓘ |
| driverDiameter | 68 inches ⓘ |
| engineWeight | about 772,000 lb ⓘ |
| factorOfAdhesion | about 4.0 ⓘ |
| firstRunYear | 1941 ⓘ |
| fuelCapacity | approximately 28 tons of coal ⓘ |
| fuelType | coal ⓘ |
| historicalEra |
World War II era
NERFINISHED
ⓘ
transition era from steam to diesel ⓘ |
| lengthOverCouplers | about 132 feet ⓘ |
| maximumSpeed | approximately 80 mph ⓘ |
| nickname | Big Boy NERFINISHED ⓘ |
| notableFor |
being among the largest steam locomotives ever built
ⓘ
being among the most powerful steam locomotives ever built ⓘ |
| numberSeries | 4000–4024 ⓘ |
| operationalUnit | Union Pacific 4014 NERFINISHED ⓘ |
| operator | Union Pacific Railroad NERFINISHED ⓘ |
| powerType | steam ⓘ |
| preservedUnitsLocation |
Cheyenne, Wyoming
NERFINISHED
ⓘ
Dallas, Texas NERFINISHED ⓘ Denver, Colorado NERFINISHED ⓘ Green Bay, Wisconsin NERFINISHED ⓘ Omaha, Nebraska NERFINISHED ⓘ Pomona, California NERFINISHED ⓘ Scranton, Pennsylvania NERFINISHED ⓘ St. Louis, Missouri NERFINISHED ⓘ |
| primaryRoute |
Ogden, Utah – Green River, Wyoming
NERFINISHED
ⓘ
Wasatch Range NERFINISHED ⓘ |
| primaryUse | heavy freight service ⓘ |
| productionEndYear | 1944 ⓘ |
| productionStartYear | 1941 ⓘ |
| railwayCompany | Union Pacific Railroad NERFINISHED ⓘ |
| retirementPeriod |
1950s
ⓘ
1960s ⓘ |
| survivingUnits | 8 ⓘ |
| totalLocomotiveAndTenderWeight | over 1,200,000 lb ⓘ |
| totalProduced | 25 ⓘ |
| tractiveEffort | approximately 135,375 lbf ⓘ |
| typicalOperatingSpeed | 35–45 mph ⓘ |
| usedOn |
Overland Route
NERFINISHED
ⓘ
Union Pacific mainline in Wyoming and Utah ⓘ |
| waterCapacity | approximately 25,000 US gallons ⓘ |
| weightOnDrivers | about 540,000 lb ⓘ |
| wheelArrangement | 4-8-8-4 ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Union Pacific Big Boy class locomotives Description of subject: The Union Pacific Big Boy class locomotives were massive 4-8-8-4 articulated steam engines built for Union Pacific Railroad, famed as some of the largest and most powerful steam locomotives ever constructed.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Union Pacific Big Boy No. 4012