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

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 WPR26LA083](https://openairdocs.org/ntsb/WPR26LA083.md): Robinson R44 · Parkman, WY · Accident · No injuries · Class 4 · Limited · Final report · Jan 19, 2026 · N996NR · 2 aircraft · Substantial damage
  > The pilots’ failure to maintain separation while conducting air work in a common operational area. Contributing to the accident was the pilots’ divided attention associated with the mission activity and unreliable radio communications.
- [NTSB CEN17LA219](https://openairdocs.org/ntsb/CEN17LA219.md): Robinson Helicopter R44 II · Douglas, WY · Accident · Serious injuries · Limited investigation · Final report · Jun 9, 2017 · N590GG · Substantial damage
  > The pilot's inability to control the helicopter's descent after encountering a sudden wind shift to a tailwind while performing a near maximum gross weight landing at a high density altitude.
- [NTSB CEN15LA387](https://openairdocs.org/ntsb/CEN15LA387.md): Robinson R44 II · Cheyenne, WY · Accident · Serious injuries · Limited investigation · Final report · Aug 28, 2015 · N440SA · Substantial damage
  > The pilot's improper preflight performance planning, which resulted in a hard landing due to low rotor rpm while operating near maximum gross weight in high density altitude conditions.

## 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" = 'WY' 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=WY

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