# NTSB ANC75AA084: Hiller Acft UH12-E, N5335V, Maunetuk River, AK, May 17, 1975

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: May 17, 1975
- Place: Maunetuk River, AK · MAUNETUK RIVER, AK
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report November 4, 1975
- Report: Brief approved by the director
- NTSB case key (mKey): 149116
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC75AA084
- Page: https://openairdocs.org/ntsb/ANC75AA084

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-3331  75/5/17  NR.MAUNETUK RIVER,AK  HILLER ACFT UH12-E  CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 31, 1718
        TIME - 1210                    N5335V              PX-  0  0  0  AIR TAXI-CARGO            TOTAL HOURS, 317 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          DAHL CREEK,AK               AVARET LAKE,AK
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            IN FLIGHT: NORMAL CRUISE
           COLLIDED WITH: TREES                                     LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           POWERPLANT - ENGINE STRUCTURE: MASTER AND CONNECTING RODS
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
           MISCELLANEOUS ACTS,CONDITIONS - PREVIOUS DAMAGE
        FACTOR(S)
           TERRAIN - HIGH OBSTRUCTIONS
        COMPLETE POWER LOSS - COMPLETE ENGINE FAILURE/FLAMEOUT-1 ENGINE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
         FIRE AFTER IMPACT
        REMARKS- NR 4 PISTON CONROD BOLTS FAILED. BELIEVE EXCESSIVE RPMS PREV APPLIED.
```

## Aircraft

- Registration: [N5335V](https://openairdocs.org/deregistered/N5335V-2017-05-22), registration cancelled 2017-05-22, S/N 2009, built 1959 (OpenAirDocs)
- Reported make and model: HILLER ACFT UH12-E
- Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs)
- Registry engine: [Lycoming VO-540 series](https://openairdocs.org/engine/lycoming-vo-540-series) (registry code 41534, reciprocating) (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 19750517038599A](https://openairdocs.org/incident/19750517038599A), May 17, 1975: Hiller UH12E, Maunetuk River, AK, Substantial damage. Nr 4 piston conrod bolts failed. Believe excessive rpms prev applied.

## Other investigations on N5335V (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 LAX95LA109](https://openairdocs.org/ntsb/LAX95LA109), Feb 15, 1995: Hiller UH-12E (N5335V), Arvin, CA, substantial damage. Probable cause: The seizure of the transmission due to lack of lubrication from a plugged oil supply line.
- [NTSB LAX79DVA42](https://openairdocs.org/ntsb/LAX79DVA42), Jun 8, 1979: Hiller UH-12E (N5335V), Porterville, CA, destroyed

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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