# NTSB SEA84IA008: S.N.I.A.S. AS350D, N350GT, Seattle, WA, October 11, 1983

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: October 10, 1983, 18:25 local (Oct 11, 1983, 01:25 UTC)
- Place: Seattle, WA
- Coordinates: 47.540229, -122.309486 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.5402&lon=-122.3095&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 39833
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA84IA008
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/39833/pdf
- Page: https://openairdocs.org/ntsb/SEA84IA008

## Analysis

THE ACFT SUSTAINED A COMPLETE FAILURE OF THE TAIL ROTOR DRINE SHAFT DUE TO FATIGUE FROM STRESS CORROSION PRECIPITATED BYPREVIOUS DAMAGE AT WHICH TIME NO LOGBOOK ENTRY WAS RECORDED TO INDICATE THAT THE SHAFT HAD BEEN INSPECTED.

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - rotor drive system,tail rotor drive shaft - failure,total (cause)
  - maintenance,major repair - inadequate, other maintenance personnel (contributing factor)
  - rotor drive system,tail rotor drive shaft - previous damage
  - rotor drive system,tail rotor drive shaft - stress corrosion
  - rotor drive system,tail rotor drive shaft - fatigue

## Aircraft

- Registration: [N350GT](https://openairdocs.org/deregistered/N350GT-1996-05-31), registration cancelled 1996-05-31, S/N 1458 (OpenAirDocs)
- Reported make and model: S.N.I.A.S. AS350D
- Registry model: [S N I A S AS350D ASTAR](https://openairdocs.org/model/s-n-i-a-s-as350d-astar) (registry code 8680803) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1458
- Airframe hours: 265
- Engines: LYCOMING LTS 101-600A2 615 horsepower turbo shaft
- Damage: No damage
- Flight: Personal, Part 91
- Registered owner: American Helicopters Corp.
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, August 12, 1983, 48 hours before
- Flight plan: Company VFR
- Airport: BFI, Boeing Field, runway 13, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 5,000 total, 370 in this make and model, 4,400 as pilot in command, 150 in the last 90 days, 50 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Dusk
- Wind: 350° at 11 knots
- Lowest ceiling: none
- Temperature: 55 °F, dew point 39 °F
- Observed at: BFI, 1 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Incident 19831010074419I](https://openairdocs.org/incident/19831010074419I), Oct 10, 1983: Snias AS350D, Seattle, WA. Tail rotor drive shaft failed on a local flight. Made safe run on landing. Tail rotor shaft failed from fatigue.

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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