# NTSB SEA79FYP21: Thorp T-18, N1947, Zillah, WA, May 11, 1979

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Closed
- Date: May 11, 1979
- Place: Zillah, WA · ZILLAH, WA
- Location: 46.4084° N, 120.2727° W: Placed by OpenAirDocs: center of Zillah, WA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=46.4084&lon=-120.2727&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed, report July 9, 1979
- Report: Brief approved by the director
- NTSB case key (mKey): 136144
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA79FYP21
- Page: https://openairdocs.org/ntsb/SEA79FYP21

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-1034  79/5/11    ZILLAH,WA           THORP T-18          CR-  0  1  0  NONCOMMERCIAL             PRIVATE, AGE 50, 701
        TIME - 1832                    N1947               PX-  0  1  0  PLEASURE/PERSONAL TRANSP  TOTAL HOURS, 80 IN TYPE,
                                       DAMAGE-DESTROYED    OT-  0  0  0                            NOT INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          PENDLETON,OR                YAKIMA,WA
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE: PROPELLER                       IN FLIGHT: NORMAL CRUISE
           COLLIDED WITH: WIRES/POLES                               LANDING: FINAL APPROACH
        PROBABLE CAUSE(S)
           POWERPLANT - PROPELLER AND ACCESSORIES: BLADES
           MISCELLANEOUS ACTS,CONDITIONS - FATIGUE FRACTURE
        FACTOR(S)
           TERRAIN - HIGH OBSTRUCTIONS
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
         FIRE AFTER IMPACT
```

## Aircraft

- Registration: [N1947](https://openairdocs.org/deregistered/N1947-1979-08-09), registration cancelled 1979-08-09, S/N 6, built 1968 (OpenAirDocs)
- Reported make and model: THORP T-18
- Registry model: [Thorp T-18](https://openairdocs.org/model/thorp-t-18) (registry code 89510TE) (OpenAirDocs)
- Category: Airplane, amateur-built
- 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 19790511011449A](https://openairdocs.org/incident/19790511011449A), May 11, 1979: Amtrth THORPT18, Zillah, WA, Substantial damage. Propeller blade failure in flight. Prop was sensenich model M74DM modified for amateur aircraft only.

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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