# NTSB NYC71FGM14: Enstrom F-28A, N4894, Marianna, PA, September 23, 1970

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: September 23, 1970
- Place: Marianna, PA · MARIANNA, PA
- Location: 40.0128° N, 80.1121° W: Placed by OpenAirDocs: center of Marianna, PA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=40.0128&lon=-80.1121&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report September 6, 1971
- Report: Brief approved by the director
- NTSB case key (mKey): 158943
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC71FGM14
- Page: https://openairdocs.org/ntsb/NYC71FGM14

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-4213  70/9/23    MARIANNA,PA         ENSTROM F-28A       CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 25, 3747
        TIME - 0740                    N4894               PX-  0  0  1  CTR CARGO-D               TOTAL HOURS, 410 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          WASHINGTON,PA               MARIANNA,PA
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE: TAIL ROTOR                      IN FLIGHT: DESCENDING
           HARD LANDING                                             LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: TAIL ROTOR GEAR BOX
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
           PERSONNEL - PRODUCTION-DESIGN-PERSONNEL: SUBSTANDARD QUALITY CONTROL
           PILOT IN COMMAND - IMPROPER OPERATION OF FLIGHT CONTROLS
           MISCELLANEOUS ACTS,CONDITIONS - SIMULATED CONDITIONS
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- TAIL ROTOR GR BOX,POROSITY HI,HARDNESS 15PCT LWR THAN SPECIFIED.
```

## Aircraft

- Registration: [N4894](https://openairdocs.org/deregistered/N4894-1999-03-12), registration cancelled 1999-03-12, S/N 046 (OpenAirDocs)
- Reported make and model: ENSTROM F-28A
- Registry model: [Enstrom F-28A](https://openairdocs.org/model/enstrom-f-28a) (registry code 3300406) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Substantial damage

## Other investigations on N4894 (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 FTW75FPA10](https://openairdocs.org/ntsb/FTW75FPA10), Sep 14, 1974: Enstrom F-28A (N4894), Dallas, TX, 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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