# NTSB investigations: Bell 47G-4A: Airframe/component/system failure/malfunction

NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports.

## Latest cases

- [NTSB LAX04LA176](https://openairdocs.org/ntsb/LAX04LA176.md): Bell 47G-4A · Bakersfield, CA · Accident · Serious injuries · Limited investigation · Final report · Apr 3, 2004 · N7NB · Substantial damage
  > a loss of tail rotor drive due to a disconnection of the drive shaft's splined coupling at the tail rotor gear box. The splined coupling to tail rotor gear box disconnection occurred as a result of tail boom flexing due to the combined effects of an…
- [NTSB ATL96LA129](https://openairdocs.org/ntsb/ATL96LA129.md): Bell 47G-4A (Soloy) · Belmont, MS · Accident · Minor injuries · Limited investigation · Final report · Sep 19, 1996 · N23PH · Substantial damage
  > failure of the aft universal joint of the tail rotor drive shaft, due to inadequate lubrication by company maintenance personnel. A factor relating to the accident was the pilot's delay in discontinuing the flight after noting a progressively worse tail rotor…
- [NTSB LAX93LA120](https://openairdocs.org/ntsb/LAX93LA120.md): Bell 47G · Bakersfield, CA · Accident · No injuries · Limited investigation · Final report · Feb 13, 1993 · N1185W · Substantial damage
  > The clutch slippage and failure of the pilot to jettison the load.
- [NTSB FTW90DPJ05](https://openairdocs.org/ntsb/FTW90DPJ05.md): Bell 47G-4A · Bixby, OK · Accident · Minor injuries · Final report · Apr 14, 1990 · N2238W · Destroyed
  > Loss of control due to undetermined mechanical failure.
- [NTSB LAX86DVA13](https://openairdocs.org/ntsb/LAX86DVA13.md): Bell 47G-4A · Shafter, CA · Accident · No injuries · Final report · Aug 8, 1986 · N1185W · Substantial damage
  > Shortly after departing the loading rig, en route to an agricultural aerial application operation, the forward coupling tail rotor drive shaft failed. The helicopter was about 10 ft above ground level and about 100 ft west of the loading rig. The pilot…
- [NTSB FTW84LA144](https://openairdocs.org/ntsb/FTW84LA144.md): Bell 47G4A · Refugio, TX · Accident · Minor injuries · Limited investigation · Final report · Feb 21, 1984 · N7956J · Destroyed
  > The helicopter was being used to herd cattle in a heavily wooded/brushy area. The plt reported he was in a hover maneuver at 50-60 ft AGL when he heard a loud sound from the rear of the helicopter. It immediately pitched nose down & started to rotate to the…

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
SELECT c."ntsbNumber", c."eventDate", c."eventType", c."eventCity", c."eventStateOrRegion", a.n_number, a."aircraftMake", a."aircraftModel", c."highestInjuryLevel", c."totalFatal", c."completionStatus", c.report_url
FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c."mKey" AND a.position = 1
WHERE c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.aircraft_model_code IN ('1181031')
    AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o."occurrenceNumber" = 1 AND o."occurrenceCode" = 130))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?model=1181031&occurrence=130

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