# NTSB investigations: Hiller UH-12E: 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 CEN26LA175](https://openairdocs.org/ntsb/CEN26LA175.md): Hiller UH-12E · Chickasha, OK · Accident · No injuries · Class 3 · Limited · Preliminary report · Apr 30, 2026 · N22SP · Substantial damage
  > On April 30, 2026, about 1730 central daylight time, a Hiller UH-12E, N22SP, was substantially damaged when it was involved in an accident near Chickasha, Oklahoma. The pilot was not injured. The helicopter was operated as a Title 14 Code of Federal…
- [NTSB CEN22LA318](https://openairdocs.org/ntsb/CEN22LA318.md): Hiller UH12E · Becker, MN · Accident · Serious injuries · Class 3 · Limited · Final report · Jul 6, 2022 · N64272 · Substantial damage
  > The in-flight failure of the main rotor mast hub due to several undetected fatigue fractures.
- [NTSB ERA21LA386](https://openairdocs.org/ntsb/ERA21LA386.md): Hiller UH-12E · Millen, GA · Accident · Minor injuries · Class 3 · Limited · Final report · Sep 29, 2021 · N430NR · Substantial damage
  > The improper reassembly of the tail rotor gearbox following maintenance, which resulted in fatigue failure of the input pinion gear shaft, and the subsequent loss of tail rotor drive.
- [NTSB WPR14LA062](https://openairdocs.org/ntsb/WPR14LA062.md): Hiller UH 12E · Chowchilla, CA · Accident · No injuries · Limited investigation · Final report · Dec 9, 2013 · N36MV · Substantial damage
  > The failure of the torsional drive coupling, which resulted in a loss of drive to the main rotor system during low-altitude flight.
- [NTSB DFW08LA100](https://openairdocs.org/ntsb/DFW08LA100.md): Hiller UH-12E · Quinton, OK · Accident · No injuries · Limited investigation · Final report · Apr 7, 2008 · N34SD · Substantial damage
  > An undetermined mechanical malfuction associated with the tail rotor drive system which led to a loss of control.

## 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.aircraft_model_code IN ('4360122', '4360137')
    AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' s WHERE s.case_mkey = x.case_mkey AND s.aircrafts_position = x.position AND s."tier2Number" = '330' AND s.case_mkey IN (SELECT case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' WHERE "isDefiningEvent")))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb-events/330/sequence?model=4360122

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