# NTSB investigations: Lycoming TVO-435-GIA: 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 DEN05LA137](https://openairdocs.org/ntsb/DEN05LA137.md): Bell 47G-3B-1 · Rock Springs, WY · Accident · No injuries · Limited investigation · Final report · Sep 13, 2005 · N24SD · Substantial damage
  > the pilot's failure to maintain control of the helicopter during the attempted autorotation after he experienced an engine overspeed that occurred for reasons undetermined.
- [NTSB SEA00FA061](https://openairdocs.org/ntsb/SEA00FA061.md): Bell 47G-3B-1 · Stanwood, WA · Accident · 1 fatal · Field investigation · Final report · Apr 2, 2000 · N3377H · Destroyed
  > The disengagement of the oil jet fitting from its threaded receptacle at the forward end of the engine crankshaft. This resulted in excessive oil within the clutch assembly, the subsequent slipping of the clutch, and ultimately the disengagement of the rotor…
- [NTSB CHI91LA257](https://openairdocs.org/ntsb/CHI91LA257.md): Bell 47G · Lake Ozark, MO · Accident · No injuries · Limited investigation · Final report · Aug 11, 1991 · N61SD · Substantial damage
  > Failure of the rotorcraft's tail boom in flight. Factors related to the accident were reduced aircraft control available to the pilot.
- [NTSB ATL91FA013](https://openairdocs.org/ntsb/ATL91FA013.md): Bell 47J-2 · Gatlinburg, TN · Accident · Serious injuries · Field investigation · Final report · Nov 1, 1990 · N49DA · Destroyed
  > The accident was inadequate maintenance of the helicopter, allowing a tail rotor drive shaft bearing to exceed wear limits. This resulted in high loads on the tail rotor drive shaft, and the resulting fatigue failure of the drive shaft.
- [NTSB DEN88FA106](https://openairdocs.org/ntsb/DEN88FA106.md): Bell 47G-3B1 · Cortez, CO · Accident · 1 fatal · Field investigation · Final report · May 7, 1988 · N8455E · Destroyed
  > The plt said that he had just taken off and reached an alt of about 300 ft when his collective control went 'limp'. The helicopter entered a descent, partially controlled by the plt using throttle and cyclic control inputs. The helicopter touched down in soft…

## 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.engine_model_code IN ('41526')
    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?engine=41526&occurrence=130

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OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.