# NTSB DEN82DA088: Aerospatiale SA315B, N48089, Thayne, WY, April 15, 1982

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Final report
- Date: April 15, 1982, 10:53 local (16:53 UTC)
- Place: Thayne, WY
- Coordinates: 42.910919, -110.999275 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.9109&lon=-110.9993&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report April 15, 1983
- Report: Approved by Office Director
- NTSB case key (mKey): 72808
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN82DA088
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/72808/pdf
- Page: https://openairdocs.org/ntsb/DEN82DA088

## Sequence of events

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

- Airframe/component/system failure/malfunction, hover
  - rotor drive system,tail rotor drive shaft - cracked (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE HELICOPTER WAS HOVERING TO PICK UP A SLING LOAD WHEN A LOUD BANG WAS HEARD AND THE AIRCRAFT BEGAN TO SPIN COUNTER CLOCKWISE. INVESTIGATION REVEALED THAT THE TAIL ROTOR DRIVE SHAFT HAD BROKEN. "EXAMINATION OF THE SHAFT BREAK DISCLOSED A SMALL FRACTURE REGION TYPICAL OF FATIGUE CRACKING."

## Aircraft

- Registration: [N48089](https://openairdocs.org/deregistered/N48089-2014-10-14), registration cancelled 2014-10-14, S/N 2397, built 1974 (OpenAirDocs)
- Reported make and model: AEROSPATIALE SA315B
- Registry model: [Aerospatiale SA315B](https://openairdocs.org/model/aerospatiale-sa315b) (registry code 8680615) (OpenAirDocs)
- Registry engine: [Turbomeca ARTOUSTEIIIB](https://openairdocs.org/engine/turbomeca-artousteiiib) (registry code 60003, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2397
- Airframe hours: 3149
- Engines: TURBO MECA ARTOUSTE IIIB 562 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Part 133
- Operator: Evergreen Helicopters, Inc.
- Registered owner: Evergreen Helicopters, Inc.
- Departed: AFTON, WY
- Destination: AFTON, WY

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 29; commercial; airplane ratings: multi-engine land, single-engine land; medical: class 2, valid medical--no waivers/lim.; flight hours: 3,270 total, 500 in this make and model, 5 as pilot in command, 50 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 10 knots
- Visibility: 10 statute miles

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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