# NTSB SEA81DYE31: Hiller UN-12D, N62377, Castle Rock, WA, June 10, 1981

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Closed
- Date: June 10, 1981
- Place: Castle Rock, WA · CASTLE ROCK, WA
- Location: 46.2719° N, 122.9037° W: Placed by OpenAirDocs: center of Castle Rock, WA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=46.2719&lon=-122.9037&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report September 10, 1981
- Report: Brief approved by the director
- NTSB case key (mKey): 125337
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA81DYE31
- Page: https://openairdocs.org/ntsb/SEA81DYE31

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-2724  81/6/10  NR.CASTLE ROCK,WA     HILLER UN-12D       CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 46, 12353
        TIME - 0930                    N62377              PX-  0  0  0  OTHER                     TOTAL HOURS, 2226 IN
                                       DAMAGE-DESTROYED    OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        DEPARTURE POINT             INTENDED DESTINATION
         CASTLE ROCK,WA               LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE: TAIL ROTOR                      IN FLIGHT: CLIMB TO CRUISE
        PROBABLE CAUSE(S)
           ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: TAIL ROTOR GEAR BOX
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - JETTISONED LOAD
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
                                  DIRECTIONAL CONTROL PROBLEM
        REMARKS- T/R INPUT BEVEL GEARSHAFT,P/N 25211-5,FAILED.LONG LINE SLING OPN.
```

## Aircraft

- Registration: [N62377](https://openairdocs.org/deregistered/N62377-2013-04-29), registration cancelled 2013-04-29, S/N 1152, built 1958 (OpenAirDocs)
- Reported make and model: HILLER UN-12D
- Registry model: [Hiller H-23D](https://openairdocs.org/model/hiller-h-23d) (registry code 4360120) (OpenAirDocs)
- Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: turbo shaft
- 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 19810610032829A](https://openairdocs.org/incident/19810610032829A), Jun 10, 1981: Hiller UH12D, Toledo, WA, Destroyed. Helicopter spun into ground uncontrolably when tail rotor drive system failed.

## Other investigations on N62377 (3)

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 SEA84LA066](https://openairdocs.org/ntsb/SEA84LA066), Mar 12, 1984: Hiller UH-12E (N62377), Forest Grove, OR, substantial damage
- [NTSB SEA82DA057](https://openairdocs.org/ntsb/SEA82DA057), Apr 23, 1982: Hiller-Soloy 12E (N62377), Christmas Valle, OR, minor damage
- [NTSB SEA80DYE03](https://openairdocs.org/ntsb/SEA80DYE03), Oct 29, 1979: Hiller Acft UH-12D (N62377), Amanda Park, WA, 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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