# NTSB investigations: Lycoming VO-540 series, OK

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 CEN09CA359](https://openairdocs.org/ntsb/CEN09CA359.md): Hiller UH-12E · Stringtown, OK · Accident · No injuries · Data collection · Final report · Jun 11, 2009 · N34SD · Substantial damage
  > The pilot's failure to maintain clearance from power lines. Contributing to the accident was the pilot's preoccupation with personal affairs.
- [NTSB DFW08LA100](https://openairdocs.org/ntsb/DFW08LA100.md): Hiller UH-12E · Quinton, OK · Accident · No injuries · Limited investigation · Final report · Apr 7, 2008 · N34SD · Substantial damage
  > An undetermined mechanical malfuction associated with the tail rotor drive system which led to a loss of control.
- [NTSB FTW95LA230](https://openairdocs.org/ntsb/FTW95LA230.md): Hiller UH-12E · Checotah, OK · Accident · Minor injuries · Limited investigation · Final report · Jun 4, 1995 · N4254X · Substantial damage
  > The pilot allowing the helicopter to touchdown improperly. A factor was the erratic running engine.
- [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 FTW79FPJ26](https://openairdocs.org/ntsb/FTW79FPJ26.md): Hiller UH12L4 · Elk City, OK · Accident · Minor injuries · Closed · Jun 22, 1979 · N90453 · Substantial damage
- [NTSB FTW76FPJ46](https://openairdocs.org/ntsb/FTW76FPJ46.md): Brantley 305 · Chattanooga, OK · Accident · Serious injuries · Closed · Sep 11, 1976 · N2231U · Destroyed
- [NTSB FTW76DPJ25](https://openairdocs.org/ntsb/FTW76DPJ25.md): Bell 47G-4 · Billings, OK · Accident · Minor injuries · Closed · Feb 25, 1976 · N1150W · Destroyed

## 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."eventStateOrRegion" = 'OK' AND c."eventCountry" = 'USA'
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41534', '41582'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41534&state=OK

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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.