M-21
E790544
The M-21 was a specialized variant of the Lockheed A-12 reconnaissance aircraft, modified to carry and launch the D-21 unmanned reconnaissance drone from its back at high altitude and speed.
All labels observed (1)
| Label | Occurrences |
|---|---|
| M-21 canonical | 3 |
How this entity was disambiguated
This entity first appeared as the object of triple T9297921 — 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: M-21 Context triple: [Lockheed A-12 program, aircraftVariantDeveloped, M-21]
-
A.
M-22
M-22 is a scenic state highway in Michigan renowned for its picturesque route along the Lake Michigan shoreline and through the Leelanau Peninsula near Traverse City.
-
B.
M-20
M-20 is a state trunkline highway in Michigan that runs east–west across the central part of the state, connecting communities such as Midland to the broader regional road network.
-
C.
M-28
M-28 is a major east–west state highway running across Michigan’s Upper Peninsula, connecting numerous communities along the southern shore of Lake Superior.
-
D.
M-115
M-115 is a state trunkline highway in Michigan that serves as a regional connector route through the central and northwestern parts of the Lower Peninsula.
-
E.
M-24
M-24 is a state highway in Michigan that serves as a key north–south transportation route through communities such as Orion Township.
- 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: M-21 Target entity description: The M-21 was a specialized variant of the Lockheed A-12 reconnaissance aircraft, modified to carry and launch the D-21 unmanned reconnaissance drone from its back at high altitude and speed.
-
A.
M-22
M-22 is a scenic state highway in Michigan renowned for its picturesque route along the Lake Michigan shoreline and through the Leelanau Peninsula near Traverse City.
-
B.
M-20
M-20 is a state trunkline highway in Michigan that runs east–west across the central part of the state, connecting communities such as Midland to the broader regional road network.
-
C.
M-28
M-28 is a major east–west state highway running across Michigan’s Upper Peninsula, connecting numerous communities along the southern shore of Lake Superior.
-
D.
M-115
M-115 is a state trunkline highway in Michigan that serves as a regional connector route through the central and northwestern parts of the Lower Peninsula.
-
E.
M-24
M-24 is a state highway in Michigan that serves as a key north–south transportation route through communities such as Orion Township.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
Lockheed aircraft
ⓘ
reconnaissance aircraft variant ⓘ |
| accidentConsequence |
death of launch control officer Ray Torick
ⓘ
loss of one M-21 airframe ⓘ |
| airframeModification |
dorsal mounting pylon for D-21
ⓘ
modified chines and fairings for drone carriage ⓘ strengthened upper fuselage ⓘ |
| basedOn | Lockheed A-12 ⓘ |
| carried | D-21 reconnaissance drone ⓘ |
| configuration | two-seat tandem cockpit ⓘ |
| countryOfOrigin |
United States
ⓘ
linked to:
United States of America
|
| crew | 2 ⓘ |
| crewPositions |
launch control officer
ⓘ
pilot ⓘ |
| designedTo |
carry D-21 reconnaissance drone
ⓘ
launch D-21 reconnaissance drone ⓘ |
| designer | Clarence "Kelly" Johnson ⓘ |
| developedFrom | A-12 reconnaissance aircraft ⓘ |
| droneMountLocation | upper rear fuselage ⓘ |
| era | Cold War ⓘ |
| firstFlightYear | 1960s ⓘ |
| launchControlSystem | rear cockpit drone control instrumentation ⓘ |
| launchEnvironment |
high altitude
ⓘ
high speed ⓘ |
| launchMethod | air launch from dorsal pylon ⓘ |
| manufacturer |
Lockheed
ⓘ
linked to:
Lockheed Aircraft Company
|
| material | titanium structure ⓘ |
| maximumSpeedClass | Mach 3+ at altitude ⓘ |
| museumDisplay | one surviving airframe on display at Museum of Flight, Seattle ⓘ |
| notableAccident | mid-air collision with D-21 during launch ⓘ |
| numberBuilt | 2 ⓘ |
| operatedFrom |
Groom Lake (Area 51)
ⓘ
linked to:
Groom Lake
|
| operationalCeilingClass | above 80,000 feet ⓘ |
| operatorType | highly classified reconnaissance operations ⓘ |
| partOfProgram | Oxcart program ⓘ |
| powerplant |
Pratt & Whitney J58 turbojet
ⓘ
linked to:
Pratt & Whitney J58
|
| primaryFunction | air-launched reconnaissance drone carrier ⓘ |
| programName | Tagboard ⓘ |
| programOutcome | manned carrier concept cancelled after accident ⓘ |
| programType | black project ⓘ |
| relatedTo |
Lockheed A-12
ⓘ
Lockheed SR-71 Blackbird ⓘ
linked to:
SR-71 Blackbird
|
| role | mothership for D-21 drone ⓘ |
| status | retired ⓘ |
| successorConcept |
B-52H carrier for D-21B
ⓘ
linked to:
B-52
|
| usedBy |
Central Intelligence Agency
ⓘ
United States Air Force ⓘ |
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: M-21 Description of subject: The M-21 was a specialized variant of the Lockheed A-12 reconnaissance aircraft, modified to carry and launch the D-21 unmanned reconnaissance drone from its back at high altitude and speed.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.