# NTSB OAK77DXQ30: Bell 47G3B1, N337RH, Rubicon Spring, CA, July 31, 1977

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Closed
- Date: July 31, 1977
- Place: Rubicon Spring, CA · RUBICON SPRING, CA
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 3 minor
- Status: Completed, report October 18, 1977
- Report: Brief approved by the director
- NTSB case key (mKey): 146247
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=OAK77DXQ30
- Page: https://openairdocs.org/ntsb/OAK77DXQ30

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-2174  77/7/31    RUBICON SPRING,CA   BELL 47G3B1         CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 30, 2353
        TIME - 1000                    N337RH              PX-  0  0  2  AIR TAXI-PASSG            TOTAL HOURS, 224 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          RUBICON SPRING,CA           LOON LAKE,CA
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            TAKEOFF: RUNNING
           COLLIDED WITH: TREES                                     LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: INADEQUATE MAINTENANCE AND INSPECTION
           POWERPLANT - IGNITION SYSTEM: SPARK PLUG
           MISCELLANEOUS ACTS,CONDITIONS - CARBON DEPOSITS
           POWERPLANT - ENGINE STRUCTURE: CRANKCASE
           MISCELLANEOUS ACTS,CONDITIONS - LOW COMPRESSION
        FACTOR(S)
           WEATHER - HIGH DENSITY ALTITUDE
        COMPLETE POWER LOSS - COMPLETE ENGINE FAILURE/FLAMEOUT-1 ENGINE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        SKY CONDITION                                            CEILING AT ACCIDENT SITE
          CLEAR                                                    UNLIMITED
        VISIBILITY AT ACCIDENT SITE                              PRECIPITATION AT ACCIDENT SITE
          5 OR OVER(UNLIMITED)                                     NONE
        OBSTRUCTIONS TO VISION AT ACCIDENT SITE                  TEMPERATURE-F
          NONE                                                      85
        WIND DIRECTION-DEGREES                                   WIND VELOCITY-KNOTS
           90                                                       5
        TYPE OF WEATHER CONDITIONS                               TYPE OF FLIGHT PLAN
          VFR                                                      NONE
        REMARKS- LEAD,OIL,AND CARBON FOULING.
```

## Aircraft

- Registration: [N337RH](https://openairdocs.org/deregistered/N337RH-2009-11-12), registration cancelled 2009-11-12, S/N 6583, built 1966 (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 TVO-435-GIA](https://openairdocs.org/engine/lycoming-tvo-435-gia) (registry code 41526, turbo-prop) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Substantial damage

## 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 19770731026649A](https://openairdocs.org/incident/19770731026649A), Jul 31, 1977: Bell 47G3B1, Rubicon Spring, CA, Substantial damage. Lead,oil,and carbon fouling.

## Other investigations on N337RH (2)

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 OAK70FXQ12](https://openairdocs.org/ntsb/OAK70FXQ12), May 21, 1970: Bell 47G3B1 (N337RH), Reno, NV, substantial damage
- [NTSB OAK67A0023](https://openairdocs.org/ntsb/OAK67A0023), Aug 11, 1966: Bell 47G3B1 (N337RH), Bridgeport, CA, 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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