# NTSB investigations: Bell 47D1: 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 LAX06LA030](https://openairdocs.org/ntsb/LAX06LA030.md): Bell 47D1 · Rancho Murieta, CA · Accident · Serious injuries · Limited investigation · Final report · Nov 10, 2005 · N16356 · Substantial damage
  > a separation of the tail rotor assembly due to the reverse bending fatigue fracture of a tail rotor pitch change link bolt, resulting in a loss of control of the helicopter, and a hard landing during the uncontrolled descent.
- [NTSB MIA98LA254](https://openairdocs.org/ntsb/MIA98LA254.md): Bell 47-D1 · Oxford, MS · Accident · Minor injuries · Limited investigation · Final report · Sep 29, 1998 · N755E · Substantial damage
  > The pilot's failure to maintain directional control due to vibration from the main rotor blade for undetermined reasons. A related finding was the improper repair of a crack in the laminant of the blue main rotor blade by other maintenance personnel.
- [NTSB MIA98LA230](https://openairdocs.org/ntsb/MIA98LA230.md): Bell 47D1 · Dawson, GA · Accident · No injuries · Limited investigation · Final report · Aug 29, 1998 · N4702S · Substantial damage
  > The pilot's selection of unsuitable terrain for landing resulting in debris being blown up during landing resulting in damage to the tail rotor and loss of control.
- [NTSB FTW98LA144](https://openairdocs.org/ntsb/FTW98LA144.md): Bell 47D1 · Jeanerette, LA · Accident · Minor injuries · Limited investigation · Final report · Mar 11, 1998 · N13012 · Substantial damage
  > The in-flight disconnect of the rotating scissors due to the separation of its hinge bolt.
- [NTSB MIA94FA125](https://openairdocs.org/ntsb/MIA94FA125.md): Bell 47D1 · Marathon, FL · Accident · 2 fatal · Field investigation · Final report · Apr 22, 1994 · N9660 · Destroyed
  > Separation of the tail rotor gearbox and tail rotor blades for an undetermined reason. Factors related to the accident were: failure of maintenance personnel to follow the proper maintenance procedure after a previous tail rotor strike, and failure to conduct…
- [NTSB ATL92LA017](https://openairdocs.org/ntsb/ATL92LA017.md): Bell 47D-1 · Rome, GA · Accident · No injuries · Limited investigation · Final report · Oct 28, 1991 · N925V · Substantial damage
  > The failure of a tail rotor blade for undetermined reasons.
- [NTSB MKC90LA144](https://openairdocs.org/ntsb/MKC90LA144.md): Bell 47D-1 · Fair Oaks, AR · Accident · Minor injuries · Limited investigation · Final report · Jul 12, 1990 · N8117 · Substantial damage
  > Tail rotor cable disengagement due to inadequate maintenance.
- [NTSB ATL89DLT03](https://openairdocs.org/ntsb/ATL89DLT03.md): Bell 47 · Shelbyville, TN · Accident · No injuries · Final report · May 12, 1989 · N908B · Substantial damage
  > Failure in the rotor drive system for unknown reasons. Contributing to the accident was the pilot's inability to perform an autorotation.
- [NTSB CHI88DEC05](https://openairdocs.org/ntsb/CHI88DEC05.md): Bell 47D1 (OH-13E) · Stockbridge, MI · Accident · No injuries · Final report · Jul 11, 1988 · N12087 · Substantial damage
  > The plt was spraying an onion field when he noted a vibration, followed by a loud noise & severe shaking of the helicopter. He attempted a forced landing, but the helicopter was unresponsive to cyclic & collective inputs. Subsequently, the right skid dug into…
- [NTSB ATL83LA315](https://openairdocs.org/ntsb/ATL83LA315.md): Bell 47D1 · Moultrie, GA · Accident · Minor injuries · Limited investigation · Final report · Aug 6, 1983 · N68632 · Substantial damage
  > After completing a swath run, the plt pulled up, made a turn, then started a let down for another pass. As he increased power, the eng RPM went from 3000 to 3100. At the same time, the plt heard a whining noise and noted that the rotor RPM was decreasing. 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 ('1180802')
    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=1180802&occurrence=130

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