# NTSB SEA85LA031: Hiller UH-12ET, N100LM, Hoquiam, WA, December 18, 1984

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: December 18, 1984, 11:00 local (19:00 UTC)
- Place: Hoquiam, WA
- Coordinates: 46.879981, -123.990226 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.8800&lon=-123.9902&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 40097
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA85LA031
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40097/pdf
- Page: https://openairdocs.org/ntsb/SEA85LA031

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of engine power(total) - nonmechanical, cruise - normal
  - reason for occurrence undetermined (cause)
- Forced landing, descent - emergency
  - autorotation - attempted, pilot in command
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - none suitable (contributing factor)
  - terrain condition - mountainous/hilly (contributing factor)
  - terrain condition - high vegetation (contributing factor)

## Analysis

PLT REPORTED THAT WHILE IN NORMAL CRUISE FLIGHT, A TOTAL LOSS OF POWER OCCURRED. AUTOROTATION WAS EFFECTED IN MOUNTAINOUS, WOODED TERRAIN. EXAMINATION OF THE ENGINE SHOWED CONTINUITY AND FREEDOM OF ROTATION. EXAMINATION OF THE FUEL SYSTEM DISCLOSED NO DISCREPANCIS.

## Aircraft

- Registration: [N100LM](https://openairdocs.org/aircraft/N100LM), registered now, S/N 1583 (OpenAirDocs)
- Reported make and model: HILLER UH-12ET
- 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
- Serial number: 1583
- Airframe hours: 2701
- Engines: ALLISON 250C-20 305 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Positioning, Part 91
- Registered owner: Airlift Helicopters
- Airworthiness certificate: Standard, Normal
- Departed: ELMA
- Destination: CRANE CREEK, WA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 5,000 total, 3,500 in this make and model, 100 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 90° at 5 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 34 °F, dew point 18 °F
- Altimeter: 30.00 inHg
- Observed at: HQM

## 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 19841218075289A](https://openairdocs.org/incident/19841218075289A), Dec 18, 1984: Hiller STCUH12, Hoquiam, WA, Substantial damage. Emergency landing onto heavily timbered and sloping terrain because of engine failure. No prist in fuel.

## 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 SEA78FYE11](https://openairdocs.org/ntsb/SEA78FYE11), Mar 6, 1978: Hiller Acft UH-12E (N100LM), Montesano, 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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