# NTSB OAK70F0086: Bell 47G3B1, N8529F, Stirling Cy, CA, July 23, 1969

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Closed
- Date: July 23, 1969
- Place: Stirling Cy, CA · STIRLING CY, CA
- Location: 39.9050° N, 121.5373° W: Placed by OpenAirDocs: center of Stirling City, CA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=39.9050&lon=-121.5373&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor, 1 uninjured
- Status: Completed, report April 13, 1970
- Report: Brief approved by the director
- NTSB case key (mKey): 163194
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=OAK70F0086
- Page: https://openairdocs.org/ntsb/OAK70F0086

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-3595  69/7/23    STIRLING CY,CALIF   BELL 47G3B1         CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 35, 8900
        TIME - 1830                    N8529F              PX-  0  0  2  ASSOC FIRE CTL ACTIVITY   TOTAL HOURS, 1400 IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          STIRLING CY,CALIF           STIRLING CY,CALIF
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            TAKEOFF: INITIAL CLIMB
           COLLIDED WITH: TREES                                     LANDING: FINAL APPROACH
        PROBABLE CAUSE(S)
           POWERPLANT - EXHAUST SYSTEM: EXTERNAL SUPERCHARGER
           MISCELLANEOUS ACTS,CONDITIONS - FATIGUE FRACTURE
           TERRAIN - HIGH OBSTRUCTIONS
        PARTIAL POWER LOSS - PARTIAL LOSS OF POWER - 1 ENGINE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- OXIDATION,COKE BUILD UP IN TURBINE WHEEL CAUSED METAL FATIGUE FAILURE.
```

## Aircraft

- Registration: [N8529F](https://openairdocs.org/deregistered/N8529F-2018-03-01), registration cancelled 2018-03-01, S/N 3386, built 1965 (OpenAirDocs)
- Reported make and model: BELL 47G3B1
- Registry model: [Bell 47G-3B-1](https://openairdocs.org/model/bell-47g-3b-1) (registry code 1181028) (OpenAirDocs)
- Registry engine: [Lycoming 0-435](https://openairdocs.org/engine/lycoming-0-435) (registry code 41516, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Substantial damage

## Other investigations on N8529F (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 DEN82FTC09](https://openairdocs.org/ntsb/DEN82FTC09), Aug 8, 1982: Bell 47G-3B-L (N8529F), Kaycee, WY, destroyed, 1 fatal

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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