# NTSB SEA77FYE24: Hiller Acft 12C, N5330V, Mt Vernon, WA, June 17, 1977

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Closed
- Date: June 17, 1977
- Place: Mt Vernon, WA · MT VERNON, WA
- Location: 48.4171° N, 122.3118° W: Placed by OpenAirDocs: center of Mount Vernon, WA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=48.4171&lon=-122.3118&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report November 30, 1977
- Report: Brief approved by the director
- NTSB case key (mKey): 146809
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA77FYE24
- Page: https://openairdocs.org/ntsb/SEA77FYE24

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-3390  77/6/17    MT VERNON,WA        HILLER ACFT 12C     CR-  0  1  0  NONCOMMERCIAL             PRIVATE, AGE 51, 400
        TIME - 1259                    N5330V              PX-  0  0  0  PRACTICE                  TOTAL HOURS, 20 IN TYPE,
                                       DAMAGE-DESTROYED    OT-  0  0  0                            NOT INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          MT VERNON,WA                LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            IN FLIGHT: NORMAL CRUISE
           HARD LANDING                                             LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: INADEQUATE MAINTENANCE AND INSPECTION
           POWERPLANT - IGNITION SYSTEM: MAGNETOS
           MISCELLANEOUS ACTS,CONDITIONS - GROUNDED
           PILOT IN COMMAND - FAILED TO FOLLOW APPROVED PROCEDURES,DIRECTIVES,ETC.
           PILOT IN COMMAND - MISJUDGED SPEED AND ALTITUDE
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - DOWNWIND
        COMPLETE POWER LOSS - COMPLETE ENGINE FAILURE/FLAMEOUT-1 ENGINE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- L MAG-P LEAD GNDD. R MAG-OIL LKG PAST SEAL INTO BRKR ASSY. DNWIND AUTOROTATION.
```

## Aircraft

- Registration: [N5330V](https://openairdocs.org/aircraft/N5330V), registered now, S/N 1042, built 1959 (OpenAirDocs)
- Reported make and model: HILLER ACFT 12C
- Registry model: [Hiller UH-12C](https://openairdocs.org/model/hiller-uh-12c) (registry code 4360116) (OpenAirDocs)
- Registry engine: [Franklin 6A&6V335 series](https://openairdocs.org/engine/franklin-6a-6v335-series) (registry code 27020, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Destroyed

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19770617031139A](https://openairdocs.org/incident/19770617031139A), Jun 17, 1977: Hiller UH12C, Mt Vernon, WA, Substantial damage. L mag-p lead gndd. R mag-oil lkg past seal into brkr assy. Dnwind autorotation.

## Other investigations on N5330V (3)

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 OAK74FVD14](https://openairdocs.org/ntsb/OAK74FVD14), Sep 14, 1973: Hiller Acft UH-12C (N5330V), Brentwood, CA, substantial damage
- [NTSB OAK71DVM12](https://openairdocs.org/ntsb/OAK71DVM12), Aug 28, 1970: Hiller Acft UH-12C (N5330V), Castroville, CA, substantial damage
- [NTSB ANC69A0052](https://openairdocs.org/ntsb/ANC69A0052), May 5, 1969: Hiller UH-12C (N5330V), Livengood, AK, 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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