# NTSB SEA91LA013: Aerospatiale SA315B Lama, N36012, Trout Lake, WA, November 8, 1990

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: November 8, 1990, 14:00 local (22:00 UTC)
- Place: Trout Lake, WA
- Coordinates: 45.969295, -121.529083 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.9693&lon=-121.5291&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report November 23, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 41360
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA013
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41360/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA013

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN CLEARANCE FROM AN OBSTACLE.

## Sequence of events

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

- In flight collision with object, maneuvering
  - weather condition - high wind (contributing factor)
  - compensation for wind conditions - inadequate, pilot in command (contributing factor)
  - object - tree(s)
  - clearance - not maintained, pilot in command (cause)
- Loss of control - in flight, maneuvering
  - directional control - not possible, pilot in command

## Analysis

DURING AN EXTERNAL LOAD OPERATION, THE PILOT HAD JUST RELEASED A LOAD OF LOGS WHEN THE HELICOPTER DRIFTED TO ONE SIDE AND THE LONG LINE BECAME ENTANGLED IN TREES. THE PILOT RELEASED THE LONG LINE BUT WAS UNABLE TO MAINTAIN CONTROL AS THE HELICOPTER COLLIDED WITH TREES AND THE TERRAIN. THE PILOT REPORTED THAT THERE WERE NO MECHANICAL FAILURES OR MALFUNCTIONS WITH THE HELICOPTER AT THE TIME OF THE ACCIDENT.

## Aircraft

- Registration: [N36012](https://openairdocs.org/deregistered/N36012-1995-05-03), registration cancelled 1995-05-03, S/N 2513 (OpenAirDocs)
- Reported make and model: AEROSPATIALE SA315B LAMA (SA315B LAM)
- Registry model: [Aerospatiale SA315B ALOUETTE III](https://openairdocs.org/model/aerospatiale-sa315b-alouette-iii) (registry code 8680516) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2513
- Engines: TURBOMECA ARTOUSTE IIIB 853 horsepower turbo shaft
- Damage: Destroyed
- Flight: Other work use, Part 133
- Operator: Rocky Mountain Helicopters
- Registered owner: Unknown

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; flight hours: 12,000 total, 1,500 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 25 knots
- Visibility: 1 statute miles
- Lowest ceiling: 500 ft overcast
- Temperature: 39 °F, dew point 39 °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 19901108049299A](https://openairdocs.org/incident/19901108049299A), Nov 8, 1990: Aerosp SA315B, Trout Lake, WA, Destroyed. Drifted after dropping load. Long line caught in trees. Lost control struck more trees demolishing helicopter.

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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