# NTSB SEA86FA073: Aerospatiale SE 318C, N4966, Siletz, OR, March 7, 1986

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: March 7, 1986, 09:40 local (17:40 UTC)
- Place: Siletz, OR
- Coordinates: 43.179134, -120.959388 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.1791&lon=-120.9594&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 40274
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA86FA073
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40274/pdf
- Page: https://openairdocs.org/ntsb/SEA86FA073

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, hover
  - engine assembly - other (cause)
  - improper use of equipment/aircraft, pilot in command (contributing factor)
  - engine assembly - burned
- Forced landing, descent - emergency
- In flight collision with terrain/water, maneuvering - turn to landing area (emergency)
  - terrain condition - mountainous/hilly (contributing factor)

## Analysis

THE PLT UNSUCCESSFULLY ATTEMPTED TO LIFT A 1597 LB LOAD OF CEDAR BLOCKS WHICH WOULD HAVE PLACED THE HELICOPTER APRX 880 LBS OVER ITS MAX GROSS WEIGHT WITH AN EXTERNAL LOAD. THE PLT WAS SETTING THE LOAD DOWN FOR GROUND PERSONNEL TO UNLOAD SOME OF THE BLOCKS WHEN A LOSS OF PWR OCCURRED. THE HELICOPTER THEN DESCENDED TO GROUND IMPACT WITH THE EXTERNAL LOAD LINE STILL ATTACHED. INSPECTION REVEALED THE ENG SUSTAINED A COMPRESSOR STALL AND THE TURBINE SECTION OF THE ENG HAD BEEN BURNED.

## Aircraft

- Registration: [N4966](https://openairdocs.org/deregistered/N4966-2012-12-18), registration cancelled 2012-12-18, S/N 2227, built 1971 (OpenAirDocs)
- Reported make and model: AEROSPATIALE SE 318C
- Registry model: [S N I A S SA 318C ALOUETTE AST](https://openairdocs.org/model/s-n-i-a-s-sa-318c-alouette-ast) (registry code 8680511) (OpenAirDocs)
- Registry engine: [Turbomeca ASTAZOU IIA](https://openairdocs.org/engine/turbomeca-astazou-iia) (registry code 60006, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2227
- Airframe hours: 2725
- Engines: ASTAZOU IIG 523 horsepower turbo shaft
- Damage: Destroyed
- Flight: Other work use, Part 133
- Operator: Lorance E. Osborne, doing business as Golden Hawk Aviation
- Registered owner: Mountainair Helicopters
- Airworthiness certificate: Standard, Normal
- Last inspection: Unknown, March 6, 1986, 1 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; commercial; instrument ratings: helicopter; medical: class 2, valid medical--no waivers/lim.; seat: center; toxicology performed; flight hours: 6,000 total, 50 in this make and model, 6,000 as pilot in command, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 5 statute miles
- Lowest ceiling: 2,500 ft broken
- Temperature: 50 °F

## 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 19860307005679A](https://openairdocs.org/incident/19860307005679A), Mar 7, 1986: Snias SA318C, Siletz, OR, Destroyed. Engine compressor stall while trying to pick up excessive load. Unable to recover before striking trees and ground.

## Other investigations on N4966 (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 ANC82FA059](https://openairdocs.org/ntsb/ANC82FA059), Jul 15, 1982: Aerospatiale SA-318C (N4966), Skwentna, AK, substantial damage
- [NTSB ANC71AA062](https://openairdocs.org/ntsb/ANC71AA062), Jun 28, 1971: Alouette II (N4966), Minchumina, AK, substantial damage, 1 fatal

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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