# NTSB investigations: Lycoming T53-L-13, WA

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 WPR18LA147](https://openairdocs.org/ntsb/WPR18LA147.md): Bell UH 1H · Olympia, WA · Accident · Serious injuries · Class 3 · Limited · Final report · May 25, 2018 · N111DR · Substantial damage
  > A loss of tail rotor thrust due to the improper installation of the tail rotor assembly by maintenance personnel resulted in the pilot’s inability to maintain control of the helicopter as he began transition into forward flight from a hover, which resulted in…
- [NTSB WPR15LA109](https://openairdocs.org/ntsb/WPR15LA109.md): Bell/Garlick UH 1H · Shelton, WA · Accident · No injuries · Limited investigation · Final report · Feb 19, 2015 · N166DR · Substantial damage
  > The fatigue failure of the engine-to-transmission driveshaft adapter attachment bolt due to the application of inadequate torque on the bolt during assembly.
- [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 SEA96FA076](https://openairdocs.org/ntsb/SEA96FA076.md): Bell UH-1H · Rainier, WA · Accident · No injuries · Field investigation · Final report · Apr 4, 1996 · N6166R · Substantial damage
  > failure of the forward power shaft (number 21) bearing. A factor relating to the accident was: the lack of suitable, unobstructed terrain for an emergency landing.
- [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.

## 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."eventStateOrRegion" = 'WA' AND c."eventCountry" = 'USA'
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41551'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

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

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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.