# NTSB UNK64X2210: Bell 47G3, N8400E, Yack Flats, MT, June 9, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: June 9, 1964
- Place: Yack Flats, MT · YACK FLATS, MT
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report August 26, 1964
- Report: Brief approved by the director
- NTSB case key (mKey): 183606
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK64X2210
- Page: https://openairdocs.org/ntsb/UNK64X2210

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
2-0406   64/6/9  NR.YACK FLATS MONT    BELL 47G3           CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 31, 1600
        TIME - 2015                    N8400E              PX-  0  0  1  POWER/PIPELINE            TOTAL HOURS, UNK/NR IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, INSTRUMENT RATED.
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            TAKEOFF: INITIAL CLIMB
           ROLL OVER                                                LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - IMPROPER OPERATION OF POWERPLANT & POWERPLANT CONTROLS
           PILOT IN COMMAND - IMPROPER OPERATION OF FLIGHT CONTROLS
           PILOT IN COMMAND - LACK OF FAMILIARITY WITH AIRCRAFT
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - ENGINE LOADED UP
           MISCELLANEOUS ACTS,CONDITIONS - AIRCRAFT CAME TO REST IN WATER
        COMPLETE POWER LOSS - COMPLETE ENGINE FAILURE/FLAMEOUT-1 ENGINE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- ENGINE POWER LAG.
```

## Aircraft

- Registration: N8400E (not matched to a registry record)
- Reported make and model: BELL 47G3
- Category: Helicopter
- Engines: reciprocating
- Damage: 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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