# NTSB investigations: Lycoming IO-540-AE1A5, IL

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 CEN25LA116](https://openairdocs.org/ntsb/CEN25LA116.md): Robinson Helicopter R44 II · Chicago, IL · Accident · No injuries · Class 3 · Limited · Preliminary report · Mar 10, 2025 · N128AF · Substantial damage
  > On March 10, 2025, about 18:30 central daylight time, a Robinson Helicopter R44 II, N128AF was substantially damaged when it was involved in an accident near Chicago, Illinois. The pilot and both passengers were not injured. The helicopter was operated under…
- [NTSB CEN23LA341](https://openairdocs.org/ntsb/CEN23LA341.md): Robinson Helicopter R44 II · Arthur, IL · Accident · Serious injuries · Class 4 · Limited · Final report · Jul 31, 2023 · N644ME · Substantial damage
  > The pilot’s failure to maintain clearance from trees during a low-level aerial application flight.
- [NTSB CEN23LA306](https://openairdocs.org/ntsb/CEN23LA306.md): Robinson Helicopter R44 II · Pocahontas, IL · Accident · No injuries · Class 3 · Limited · Final report · Jul 14, 2023 · N62RK · Substantial damage
  > A reported loss of engine power for undetermined reasons.
- [NTSB CEN21LA369](https://openairdocs.org/ntsb/CEN21LA369.md): Robinson Helicopter R44 II · Wheeling, IL · Accident · Minor injuries · Class 3 · Limited · Final report · Aug 11, 2021 · N4043B · Substantial damage
  > A partial loss of engine power for reasons that could not be determined based on available information.
- [NTSB GAA18CA430](https://openairdocs.org/ntsb/GAA18CA430.md): Robinson R44 · Okawville, IL · Accident · No injuries · Data collection · Final report · Jul 9, 2018 · N944DC · Substantial damage
  > The pilot's improper preflight weight and balance calculation, which resulted in his operating the helicopter over its maximum gross takeoff weight and in its subsequent failure to climb.
- [NTSB CEN15LA198](https://openairdocs.org/ntsb/CEN15LA198.md): Robinson Helicopter R44 II · Dunlap, IL · Accident · No injuries · Limited investigation · Final report · Apr 15, 2015 · N754R · Substantial damage
  > A loss of main rotor rpm for reasons that could not be determined during postaccident examinations.

## 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" = 'IL' 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 ('41899'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41899&state=IL

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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.