# NTSB investigations: Lycoming T-53 series, 1993

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 ATL94LA035](https://openairdocs.org/ntsb/ATL94LA035.md): Kaman HH-43B/F · Mobile, AL · Accident · No injuries · Limited investigation · Final report · Dec 29, 1993 · N5197W · Substantial damage
  > An inadequate major repair by company maintenance personnel who failed to install the cotter pin which secured the retaining nut of the right main rotor hub teeter pin.
- [NTSB SEA93LA207](https://openairdocs.org/ntsb/SEA93LA207.md): Bell UH-1B · Pierce, ID · Accident · No injuries · Limited investigation · Final report · Sep 23, 1993 · N3979C · Substantial damage
  > Separation of the 90 degree gearbox after fatigue failure of the gearbox attach bolts. Factors include hilly/mountainous terrain.
- [NTSB ANC93FA056](https://openairdocs.org/ntsb/ANC93FA056.md): Bell 204B · Copper Harbor, AK · Accident · 1 fatal · Field investigation · Final report · May 2, 1993 · N204AQ · Destroyed
  > Fatigue failure of the tail rotor gearbox, and improper helicopter operations being conducted by the operator resulting in repetitive at and over maximum loads. Factors in the accident were: material defect of the tail rotor gear box (inadequate quality…
- [NTSB ATL93LA075](https://openairdocs.org/ntsb/ATL93LA075.md): Bell UH1F · Gatlinburg, TN · Accident · Minor injuries · Limited investigation · Final report · Apr 16, 1993 · N4040P · Substantial damage
  > The loss of engine power for unknown reasons.

## 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") = 1993
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41552', '41549', '41587'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41552&year=1993

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