# NTSB investigations: Allison 250 SER 250HP, 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 WPR26LA277](https://openairdocs.org/ntsb/WPR26LA277.md): Bell 206B III · Stonewall, OK · Accident · Serious injuries · Class 4 · Limited · Final report · Jul 21, 2026 · N2193X · Substantial damage
  > The pilot’s failure to maintain clearance from power lines while conducting a low-altitude aerial application.
- [NTSB CEN11LA200](https://openairdocs.org/ntsb/CEN11LA200.md): Hughes 369D · Henryetta, OK · Accident · No injuries · Limited investigation · Final report · Feb 23, 2011 · N112AS · Substantial damage
  > Failure of the cyclic control system for reasons undetermined.
- [NTSB FTW84LA081](https://openairdocs.org/ntsb/FTW84LA081.md): Bell 206L-1 · Ardmore, OK · Accident · Minor injuries · Limited investigation · Final report · Dec 2, 1983 · N2005A · Substantial damage
  > The plt stated that before he took off from Oklahoma city, OK, he called the Oklahoma city fss & obtained a wx briefing. The briefing called for light rain showers, minimum ceiling of 1800 ft, visibility of 3 to 5 miles & no chance of fog, except in low lying…
- [NTSB FTW81FA023](https://openairdocs.org/ntsb/FTW81FA023.md): Bell 206B · Norman, OK · Accident · 5 fatal · Closed · Jan 9, 1981 · N10785 · Destroyed
- [NTSB FTW72AF079](https://openairdocs.org/ntsb/FTW72AF079.md): Hiller Acft FH1100 · Yukon, OK · Accident · No injuries · Closed · May 19, 1972 · N748FH · 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 ('03002', '03003'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=03002&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.