# NTSB investigations: Lycoming VO-435 series, 1999

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 ATL99FA132](https://openairdocs.org/ntsb/ATL99FA132.md): Continental Copters Tomcat MK5A · Heflin, AL · Accident · 2 fatal · Field investigation · Final report · Sep 16, 1999 · N9010T · 2 aircraft · Destroyed
  > The pilot of N9010T's failure to maintain visual lookout while maneuvering, resulting in a midair collision with N30899. A factor was the sun glare.
- [NTSB SEA99LA149](https://openairdocs.org/ntsb/SEA99LA149.md): Bell 47G-2 · Benton City, WA · Accident · 1 fatal · Limited investigation · Final report · Aug 26, 1999 · N11VH · Destroyed
  > A loss of power for undetermined reasons and the failure of the pilot to maintain adequate rotor RPM following the power loss. Contributing factors were the pilot's lack of certification and total experience.
- [NTSB FTW99TA194](https://openairdocs.org/ntsb/FTW99TA194.md): Bell 47G-3B-1 · Sour Lake, TX · Accident · No injuries · Final report · Jul 17, 1999 · N4002G · Substantial damage
  > The pilot's failure to adequately preflight the helicopter's fuel system resulting in the total loss of engine power as a result of water contamination. Factors were the incorrect filter installed on the fueling truck and the pilot's improper touchdown…
- [NTSB ATL99LA107](https://openairdocs.org/ntsb/ATL99LA107.md): Continental Copters Tomcat MK5A · Camden, AL · Accident · Minor injuries · Limited investigation · Final report · Jul 14, 1999 · N9086T · Substantial damage
  > The failure of the cyclic control rod due to an overstress separation resulting from a material defect (inadequate quality of material) by the manufacturer.
- [NTSB LAX99LA081](https://openairdocs.org/ntsb/LAX99LA081.md): Hiller UH-12E · Lemoore, CA · Accident · No injuries · Limited investigation · Final report · Jan 24, 1999 · N67064 · Substantial damage
  > The inadequate nature of the operator's maintenance, which failed to detect the primer and magneto discrepancies. An overly lean fuel mixture and/or magneto cross firing resulted in detonation, an ensuing connecting rod failure, and a total loss of engine…

## 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 year(c."eventDate") = 1999
  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&year=1999

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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.