# NTSB investigations: Lycoming TVO-435-GIA, 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 DEN99LA168](https://openairdocs.org/ntsb/DEN99LA168.md): Bell 47G3B2A · Tremonton, UT · Accident · No injuries · Limited investigation · Final report · Sep 23, 1999 · N83246 · Substantial damage
  > The pilot's failure to maintain rotor rpm while attempting a precautionary autorotation landing. A factor was the loss of engine power for undetermined reasons.
- [NTSB MIA99LA217](https://openairdocs.org/ntsb/MIA99LA217.md): Bell 47G-B3 · Selma, AL · Accident · No injuries · Limited investigation · Final report · Aug 8, 1999 · N6712D · Substantial damage
  > The pilot's failure to maintain the proper touchdown point during landing causing the landing skid to become entangled with the edge of the helipad platform and the resultant rollover and main rotor blade strike of the tow vehicle.
- [NTSB ATL99LA105](https://openairdocs.org/ntsb/ATL99LA105.md): Bell 47 · Trenton, GA · Accident · Minor injuries · Limited investigation · Final report · Jul 2, 1999 · N23590 · Substantial damage
  > The loss of main rotor rpm due to improper use of the flight controls by the pilot. Factors were the tailwind and trees.
- [NTSB SEA99LA098](https://openairdocs.org/ntsb/SEA99LA098.md): Bell 47G3B2A · Pendleton, OR · Accident · No injuries · Limited investigation · Final report · Jun 10, 1999 · N24MP · Substantial damage
  > A fouled external load cable, and the pilot's operation of the helicopter with a non-approved external bucket installation, resulting in misrouted hydraulic lines and consequent malfunction of the external load release system.

## 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 ('41526'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41526&year=1999

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