# NTSB investigations: Lycoming T53-L-13: Airframe/component/system failure/malfunction

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 SEA02FA108](https://openairdocs.org/ntsb/SEA02FA108.md): Garlick UH-1H · Clark Fork, ID · Accident · 1 fatal · Field investigation · Final report · Jun 21, 2002 · N114DR · Substantial damage
  > A failure of unknown origin in the tail rotor drive assembly. Factors include mountainous terrain unsuitable for an emergency landing.
- [NTSB SEA97LA025](https://openairdocs.org/ntsb/SEA97LA025.md): Garlick TH-1L · Leavenworth, WA · Accident · 1 fatal · Limited investigation · Final report · Nov 5, 1996 · N465JR · Destroyed
  > Fatigue failure of the vertical stabilizer spar cap and subsequent loss of the rotorcraft's vertical stabilizer. Factors include inadequate inspection or trouble-shooting of the aircraft tail cone and vertical stabilizer at and after the time sheet-metal…
- [NTSB LAX94LA132](https://openairdocs.org/ntsb/LAX94LA132.md): Bell TH-1L · Etna, CA · Accident · Minor injuries · Limited investigation · Final report · Feb 23, 1994 · N204AP · Substantial damage
  > The faituge of the gear tooth which caused the failure of the 42-degree gear box.
- [NTSB SEA89FA111](https://openairdocs.org/ntsb/SEA89FA111.md): Oregon Helicopters UH-1L · Baring, WA · Accident · Serious injuries · Field investigation · Final report · Jun 14, 1989 · N157LC · Destroyed
  > Fatigue failure of the tail rotor 42 degree gear box due to pilot induced overstress. Navy data and FAA type certificate limitations were not adhered to.
- [NTSB MIA89LA081](https://openairdocs.org/ntsb/MIA89LA081.md): Bell TH-1L · Greenville, FL · Accident · No injuries · Limited investigation · Final report · Feb 8, 1989 · N204AP · Substantial damage
  > Installation of the improper sprag clutch assembly by the owners maintenance personnel resulting in failure of the sprag clutch and the loss of transmission drive.
- [NTSB ATL88FA213](https://openairdocs.org/ntsb/ATL88FA213.md): Bell TH-1L · Walterboro, SC · Accident · Serious injuries · Field investigation · Final report · Jul 12, 1988 · N465JR · Substantial damage
  > The military surplus helicopter experienced a 42 degree gear box failure while lifting a load of logs. The helicopter subsequently landed hard as the plt was attempting to autorotate to a ldg. Metallurgical examination of the gearbox revealed that a gear…

## 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."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41551')
    AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o."occurrenceNumber" = 1 AND o."occurrenceCode" = 130))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41551&occurrence=130

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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.