# NTSB investigations: Lycoming TVO-435-GIA, 1991

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 FTW92LA026](https://openairdocs.org/ntsb/FTW92LA026.md): Bell 47G3B2A · Texarkana, TX · Accident · Serious injuries · Limited investigation · Final report · Nov 24, 1991 · N8134J · Substantial damage
  > The pilot's failure to maintain proper terrain clearance during takeoff. A factor was his lack of total experience in helicopters.
- [NTSB NYC92LA006](https://openairdocs.org/ntsb/NYC92LA006.md): Bell 47G-3B-1 · Catawissa, PA · Accident · Minor injuries · Limited investigation · Final report · Oct 12, 1991 · N5NH · Substantial damage
  > Pilot factor in that the pilot used poor judgement and loaded more passengers than were seats on the helicopter this resulted in control interference and subsequent loss of control. Contributing was the pilot's failure to check the weight and balance for the…
- [NTSB MIA91LA217](https://openairdocs.org/ntsb/MIA91LA217.md): Bell 47G-3B-1 · Penuelas, PR · Accident · No injuries · Limited investigation · Final report · Sep 15, 1991 · N1397X · Substantial damage
  > Inadvertent control interference by a passenger shortly after takeoff resulting in the loss of control and roll over after touchdown.
- [NTSB CHI91LA257](https://openairdocs.org/ntsb/CHI91LA257.md): Bell 47G · Lake Ozark, MO · Accident · No injuries · Limited investigation · Final report · Aug 11, 1991 · N61SD · Substantial damage
  > Failure of the rotorcraft's tail boom in flight. Factors related to the accident were reduced aircraft control available to the pilot.
- [NTSB DEN91LA096](https://openairdocs.org/ntsb/DEN91LA096.md): Bell 47G-3B-1 · Colorado Spring, CO · Accident · No injuries · Limited investigation · Final report · Jul 4, 1991 · N40DP · Substantial damage
  > The pilot attempting to operate the helicopter outside the design operating envelope. Factors were: high altitude, high temperature, and high density altitude.
- [NTSB CHI91DER05](https://openairdocs.org/ntsb/CHI91DER05.md): Bell 47G3B1 · Lasalle, MN · Accident · No injuries · Final report · Jun 11, 1991 · N73284 · Substantial damage
  > The pilot's failure to maintain adequate clearance from the terrain. A related factor is the pilot's misjudged altitude above the crop.
- [NTSB SEA91LA109](https://openairdocs.org/ntsb/SEA91LA109.md): Bell 47G-3B-1 · Malott, WA · Accident · No injuries · Limited investigation · Final report · May 19, 1991 · N73903 · Destroyed
  > An undetermined failure of the fuel pump casing resulting in an in flight fire and loss of engine power.

## 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") = 1991
  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=1991

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