# NTSB investigations: Lycoming VO-435 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 FTW94FA158](https://openairdocs.org/ntsb/FTW94FA158.md): Bell 47G-2 · Tulsa, OK · Accident · 1 fatal · Field investigation · Final report · May 16, 1994 · N47GY · Destroyed
  > In flight loss of control due to the pilot's improper use of the cyclic and collective controls when he maneuvered abruptly to avoid colliding with a flock of birds. Factors were the birds and the inflight separation of the left synchronized elevator.
- [NTSB FTW87DPJ09](https://openairdocs.org/ntsb/FTW87DPJ09.md): G&C Helicopters EL Tomcat MK5A · Marlow, OK · Accident · Serious injuries · Final report · Sep 23, 1987 · N17315 · Substantial damage
  > Pilot failed to see and avoid tree at end of swath run during a spraying operation. After contacting the tree, the helicopter started to spin and struck the ground in an approximate 90 degree right bank and started to burn.
- [NTSB FTW83FA311](https://openairdocs.org/ntsb/FTW83FA311.md): Bell 47G-2 · Bethany, OK · Accident · Minor injuries · Field investigation · Final report · Jul 3, 1983 · N2495B · Destroyed
  > The helicopter collided with trees and rolled over during a forced landing after engine failure. The plt had been takingpassengers up for sight-seeing for several hours. After the last flt he and his wife had departed the city park to fly back to the acft…
- [NTSB FTW81DPJ24](https://openairdocs.org/ntsb/FTW81DPJ24.md): Bell 47D1 · Okeene, OK · Accident · No injuries · Closed · Apr 25, 1981 · N7768 · Substantial damage
- [NTSB FTW80DPJ20](https://openairdocs.org/ntsb/FTW80DPJ20.md): Hiller Acft HU-12D · Norman, OK · Accident · No injuries · Closed · May 13, 1980 · N102BC · Substantial damage
- [NTSB FTW76DPJ49](https://openairdocs.org/ntsb/FTW76DPJ49.md): Bell 47G-2 · Elgin, OK · Accident · Minor injuries · Closed · Aug 14, 1976 · N13299 · Destroyed
- [NTSB FTW74FPJ06](https://openairdocs.org/ntsb/FTW74FPJ06.md): EL Tomcat MK5 · Springer, OK · Accident · 1 fatal · Closed · Aug 16, 1973 · N11VH · Substantial damage
- [NTSB FTW72DPM26](https://openairdocs.org/ntsb/FTW72DPM26.md): Bell 47G · Wynona, OK · Accident · No injuries · Closed · Apr 5, 1972 · N993B · Substantial damage
- [NTSB UNK65X0693](https://openairdocs.org/ntsb/UNK65X0693.md): Bell 47G2A · Yukon, OK · Accident · No injuries · Closed · Nov 13, 1964 · N3355D · 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" = '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 ('41525'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

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