# NTSB SEA78FYE11: Hiller Acft UH-12E, N100LM, Montesano, WA, March 6, 1978

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: March 6, 1978
- Place: Montesano, WA · MONTESANO, WA
- Location: 47.0147° N, 123.5857° W: Placed by OpenAirDocs: center of Montesano, WA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=47.0147&lon=-123.5857&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 12, 1978
- Report: Brief approved by the director
- NTSB case key (mKey): 143254
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA78FYE11
- Page: https://openairdocs.org/ntsb/SEA78FYE11

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-0555   78/3/6    MONTESANO,WA        HILLER ACFT UH-12E  CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 36, 2925
        TIME - 1100                    N100LM              PX-  0  0  0  OTHER                     TOTAL HOURS, UNK/NR IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          MONTESANO,WA                LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE: MAIN ROTOR                      IN FLIGHT: OTHER
           ROLL OVER                                                LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: MAIN ROTOR INTERMEDIATE GEARS
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
        FACTOR(S)
           TERRAIN - ROUGH/UNEVEN
           MISCELLANEOUS ACTS,CONDITIONS - JETTISONED LOAD
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- CARRYING CEDAR BLOCKS. 2ND STAGE REDUCTION GEAR  FAILED. LND ON HILL SIDE.
```

## Aircraft

- Registration: [N100LM](https://openairdocs.org/aircraft/N100LM), registered now, S/N 1583 (OpenAirDocs)
- Reported make and model: HILLER ACFT UH-12E
- Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs)
- Registry engine: [Allison 250-C20 series](https://openairdocs.org/engine/allison-250-c20-series) (registry code 03020, 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 19780306006809A](https://openairdocs.org/incident/19780306006809A), Mar 6, 1978: Hiller OH23G, Montesano, WA, Substantial damage. Carrying cedar blocks. 2nd stage reduction gear failed. Landed on side

## Other investigations on N100LM (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 LAX93LA319](https://openairdocs.org/ntsb/LAX93LA319), Aug 11, 1993: Hiller UH-12E (N100LM), Dixon, CA, destroyed. Probable cause: the failure of the pilot to visually detect and avoid the guy wire.
- [NTSB SEA85LA031](https://openairdocs.org/ntsb/SEA85LA031), Dec 18, 1984: Hiller UH-12ET (N100LM), Hoquiam, 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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