# NTSB UNK64X3151: Mooney MK20C, N6751U, Okla City, OK, August 1, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: August 1, 1964
- Place: Okla City, OK · OKLA CITY, OK
- Location: 35.4676° N, 97.5164° W: Placed by OpenAirDocs: center of Oklahoma City, OK, within about 14 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=35.4676&lon=-97.5164&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report October 20, 1964
- Report: Brief approved by the director
- NTSB case key (mKey): 182254
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK64X3151
- Page: https://openairdocs.org/ntsb/UNK64X3151

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-2291   64/8/1    OKLA CITY OKLA      MOONEY MK20C        CR-  0  0  1  NONCOMMERCIAL             PRIVATE, AGE 27, 650
        TIME - 1730                    N6751U              PX-  0  0  0  BUSINESS                  TOTAL HOURS, 25 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE                                  IN FLIGHT: CLIMB TO CRUISE
           HARD LANDING                                             LANDING: LEVEL OFF/TOUCHDOWN
        PROBABLE CAUSE(S)
           MISCELLANEOUS ACTS,CONDITIONS - UNAPPROVED MODIFICATION
           MISCELLANEOUS ACTS,CONDITIONS - WRONG PART
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: IMPROPER MAINTENANCE (MAINTENANCE PERSONNEL)
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: INADEQUATE INSPECTION OF AIRCRAFT (MAINTENANCE PERSONNEL)
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- PROPELLER WENT INTO FEATHERED POSITION. IMPROPER PROPELLER FOR MODEL AIRCRAFT.
```

## Aircraft

- Registration: [N6751U](https://openairdocs.org/deregistered/N6751U-2018-03-02), registration cancelled 2018-03-02, S/N 2473, built 1963 (OpenAirDocs)
- Reported make and model: MOONEY MK20C
- Registry model: [Mooney M20C](https://openairdocs.org/model/mooney-m20c) (registry code 5870208) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane
- Engines: reciprocating
- Damage: Substantial damage

## Other investigations on N6751U (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB UNK64X1335](https://openairdocs.org/ntsb/UNK64X1335), Apr 16, 1964: Mooney M20C (N6751U), Gretna, VA, substantial damage

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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