# NTSB UNK64X2338: Mooney MK21, N6959U, Boss, MO, June 17, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: June 17, 1964
- Place: Boss, MO · BOSS, MO
- Location: 37.6431° N, 91.1893° W: Placed by OpenAirDocs: center of Boss, MO, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=37.6431&lon=-91.1893&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed, report October 2, 1964
- Report: Brief approved by the director
- NTSB case key (mKey): 183384
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK64X2338
- Page: https://openairdocs.org/ntsb/UNK64X2338

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-1690  64/6/17    BOSS MO             MOONEY MK21         CR-  0  0  1  NONCOMMERCIAL             PRIVATE, AGE 44, 700
        TIME - 1915                    N6959U              PX-  0  0  2  BUSINESS                  TOTAL HOURS, 15 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           GEAR COLLAPSED                                           LANDING: ROLL
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - BECAME LOST/DISORIENTED
           PILOT IN COMMAND - SELECTED UNSUITABLE TERRAIN
           TERRAIN - WET,SOFT GROUND
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - OVERLOAD FAILURE
        EMERGENCY CIRCUMSTANCES - PRECAUTIONARY LANDING OFF AIRPORT
```

## Aircraft

- Registration: [N6959U](https://openairdocs.org/deregistered/N6959U-2003-04-07), registration cancelled 2003-04-07, S/N 2710, built 1964 (OpenAirDocs)
- Reported make and model: MOONEY MK21
- 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 N6959U (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 LAX94LA275](https://openairdocs.org/ntsb/LAX94LA275), Jul 5, 1994: Mooney M20C (N6959U), Las Vegas, NV, substantial damage. Probable cause: THE FAILURE OF THE PILOT TO OBTAIN THE PROPER TAKEOFF SPEED. FACTORS ARE THE HIGH DENSITY ALTITUDE AND THE CROSSWIND.

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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