# NTSB investigations: Lycoming O-540-F1B5: Sys/Comp malf/fail (non-power)

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 CEN26LA259](https://openairdocs.org/ntsb/CEN26LA259.md): Robinson Helicopter R44 · Adair, IA · Accident · No injuries · Class 3 · Limited · Preliminary report · Jul 18, 2026 · N484AT · Substantial damage
  > On July 18, 2026, about 1440 central daylight time, a Robinson Helicopter Company R44, N484AT, was substantially damaged when it was involved in an accident near Adair, Iowa. The pilot was not injured. The helicopter was operated as a Title 14 Code of Federal…
- [NTSB ANC24LA077](https://openairdocs.org/ntsb/ANC24LA077.md): Robinson R44 · Honolulu, HI · Accident · No injuries · Class 3 · Limited · Final report · Aug 19, 2024 · N740RH · Substantial damage
  > A failure of the flex plate yoke flange assembly due to incorrectly torqued bolts. Contributing was the maintenance personnel’s inadequate inspection of the tail rotor flex plate assembly.
- [NTSB ERA22LA256](https://openairdocs.org/ntsb/ERA22LA256.md): Robinson Helicopter R44 · North Myrtle Beach, SC · Accident · No injuries · Class 3 · Limited · Final report · May 26, 2022 · N132TC · Substantial damage
  > The fractured attachment lug on the forward clutch shaft yoke due to fatigue failure with multiple origins.

## 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 ('42353')
    AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' e WHERE e.case_mkey = x.case_mkey AND e.aircrafts_position = x.position AND e."isDefiningEvent" AND e."tier2Number" = '330'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb-events/330/cases?engine=42353

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