# NTSB investigations: Lycoming VO-435 series, SD

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 CEN12LA557](https://openairdocs.org/ntsb/CEN12LA557.md): Bell 47G-2 · Flandreau, SD · Accident · No injuries · Limited investigation · Final report · Aug 14, 2012 · N444EH · Substantial damage
  > A malfunction of the helicopter’s throttle system, which resulted in a loss of engine power during cruise flight.
- [NTSB CHI05CA147](https://openairdocs.org/ntsb/CHI05CA147.md): Bell 47G · Twin Brooks, SD · Accident · Minor injuries · Data collection · Final report · May 19, 2005 · N8505F · Substantial damage
  > The pilot's inadequate lookout and his failure to maintain clearance with the power lines. A factor was the low altitude at which the helicopter was operating.
- [NTSB CHI97LA004](https://openairdocs.org/ntsb/CHI97LA004.md): Bell 47G-5 · Nunda, SD · Accident · No injuries · Limited investigation · Final report · Oct 6, 1996 · N7925J · Substantial damage
  > failure of maintenance personnel to properly torque the six accessory drive bolts, which resulted in fatigue failure of the undertorqued bolts.
- [NTSB MKC76AK012](https://openairdocs.org/ntsb/MKC76AK012.md): Bell 47G-5 · Keystone, SD · Accident · 3 fatal · Closed · Aug 5, 1975 · N4753R · Substantial damage
- [NTSB MKC76FTK02](https://openairdocs.org/ntsb/MKC76FTK02.md): Bell 47-G2A · Keystone, SD · Accident · Minor injuries · Closed · Jul 25, 1975 · N7578 · Substantial damage
- [NTSB MKC69F0086](https://openairdocs.org/ntsb/MKC69F0086.md): Bell 47G-2 · Interior, SD · Accident · Minor injuries · Closed · Aug 1, 1968 · N2813B · Substantial damage
- [NTSB MKC66A0005](https://openairdocs.org/ntsb/MKC66A0005.md): Bell 47G2 · Keystone, SD · Accident · No injuries · Closed · Jul 22, 1965 · N262MV · Substantial damage

## 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" = 'SD' 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 ('41525'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41525&state=SD

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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.