SP 4257
E668255
SP 4257 is a preserved Southern Pacific AC-11 class articulated steam locomotive, notable as one of the railroad’s powerful cab-forward engines used in heavy freight service.
All labels observed (1)
| Label | Occurrences |
|---|---|
| SP 4257 canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T7429191 — 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: SP 4257 Context triple: [AC-11, fleetNumbers, SP 4257]
-
A.
SP 4247
SP 4247 is a Southern Pacific Railroad AC-11 class articulated steam locomotive, part of the railroad’s well-known cab-forward fleet used primarily in heavy freight service.
-
B.
SP 4249
SP 4249 is a Southern Pacific Railroad AC-11 class articulated steam locomotive, part of the railroad’s famous cab-forward fleet used primarily in heavy freight service.
-
C.
SP 4267
SP 4267 is a preserved Southern Pacific AC-11 class articulated steam locomotive, notable as one of the railroad’s powerful cab-forward engines used in heavy freight service.
-
D.
SP 4245
SP 4245 is a Southern Pacific Railroad EMD AC-11 class articulated steam locomotive, part of a series of powerful cab-forward engines used primarily for heavy freight service over mountainous routes.
-
E.
SP 4250
SP 4250 is a Southern Pacific Railroad AC-11 class articulated steam locomotive, part of the railroad’s famous cab-forward fleet used primarily for heavy freight service.
- 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: SP 4257 Target entity description: SP 4257 is a preserved Southern Pacific AC-11 class articulated steam locomotive, notable as one of the railroad’s powerful cab-forward engines used in heavy freight service.
-
A.
SP 4247
SP 4247 is a Southern Pacific Railroad AC-11 class articulated steam locomotive, part of the railroad’s well-known cab-forward fleet used primarily in heavy freight service.
-
B.
SP 4249
SP 4249 is a Southern Pacific Railroad AC-11 class articulated steam locomotive, part of the railroad’s famous cab-forward fleet used primarily in heavy freight service.
-
C.
SP 4267
SP 4267 is a preserved Southern Pacific AC-11 class articulated steam locomotive, notable as one of the railroad’s powerful cab-forward engines used in heavy freight service.
-
D.
SP 4245
SP 4245 is a Southern Pacific Railroad EMD AC-11 class articulated steam locomotive, part of a series of powerful cab-forward engines used primarily for heavy freight service over mountainous routes.
-
E.
SP 4250
SP 4250 is a Southern Pacific Railroad AC-11 class articulated steam locomotive, part of the railroad’s famous cab-forward fleet used primarily for heavy freight service.
- F. None of above. chosen
Statements (27)
| Predicate | Object |
|---|---|
| instanceOf | steam locomotive ⓘ |
| category |
Southern Pacific AC-11 locomotives
ⓘ
linked to:
Southern Pacific Cab Forward locomotive
articulated steam locomotives ⓘ cab-forward steam locomotives ⓘ preserved steam locomotives in the United States ⓘ |
| configuration |
articulated
ⓘ
cab-forward ⓘ |
| country |
United States
ⓘ
linked to:
United States of America
|
| designFeature |
articulated engine units
ⓘ
cab located at front of locomotive ⓘ |
| fuelType | bunker oil ⓘ |
| gauge | standard gauge ⓘ |
| heritageStatus | preserved ⓘ |
| historicalOperator |
Southern Pacific Transportation Company
ⓘ
linked to:
Southern Pacific Railroad
|
| locomotiveClass | Southern Pacific AC-11 ⓘ |
| notableFor |
being a powerful cab-forward locomotive
ⓘ
service on mountain grades of the Southern Pacific ⓘ |
| operator | Southern Pacific Railroad ⓘ |
| partOfClass |
Southern Pacific AC-11 class
ⓘ
linked to:
Southern Pacific AC-11
|
| powerType | steam ⓘ |
| railwayCompany |
Southern Pacific
ⓘ
linked to:
Southern Pacific Railroad
|
| railwayLine | Southern Pacific Railroad ⓘ |
| railwayRole | road freight locomotive ⓘ |
| regionServed |
Western United States
ⓘ
linked to:
western United States
|
| traction | steam-powered driving wheels ⓘ |
| use |
freight service
ⓘ
heavy freight service ⓘ |
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: SP 4257 Description of subject: SP 4257 is a preserved Southern Pacific AC-11 class articulated steam locomotive, notable as one of the railroad’s powerful cab-forward engines used in heavy freight service.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.