# NTSB investigations: Hiller UH-12E: Collision with terr/obj (non-CFIT)

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 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 WPR15LA138](https://openairdocs.org/ntsb/WPR15LA138.md): Hiller UH 12E · Firebaugh, CA · Accident · No injuries · Limited investigation · Final report · Mar 29, 2015 · N130HA · Substantial damage
  > A loss of engine power for reasons that could not be determined because postaccident examination of the engine did not reveal any anomalies that would have precluded normal operation.
- [NTSB ERA14LA405](https://openairdocs.org/ntsb/ERA14LA405.md): Hiller UH 12E · Cape May Court House, NJ · Accident · Minor injuries · Limited investigation · Final report · Aug 25, 2014 · N4035A · Substantial damage
  > The mechanic’s failure to detect excessive wear on the engine’s lateral snubber vibration mount during the latest annual inspection, which resulted in an in-flight engine failure and a subsequent forced landing.
- [NTSB ERA14LA361](https://openairdocs.org/ntsb/ERA14LA361.md): Hiller UH 12E · Wadesboro, NC · Accident · No injuries · Limited investigation · Final report · Jul 26, 2014 · N107HA · Substantial damage
  > A partial loss of engine power due to the failure of the No. 2 engine accessory gearbox bearing for reasons that could not be determined based on the available information.
- [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 WPR11LA244](https://openairdocs.org/ntsb/WPR11LA244.md): Hiller UH-12E · Stockton, CA · Accident · No injuries · Limited investigation · Final report · Jun 1, 2011 · N68012 · Substantial damage
  > The pilot's failure to maintain clearance from obstacles.
- [NTSB WPR11CA146](https://openairdocs.org/ntsb/WPR11CA146.md): Hiller UH-12E · Colusa, CA · Accident · No injuries · Data collection · Final report · Feb 26, 2011 · N236HA · Substantial damage
  > The pilot's failure to maintain an adequate airspeed and an inadvertent encounter with settling with power while flying downwind.
- [NTSB WPR10CA466](https://openairdocs.org/ntsb/WPR10CA466.md): Hiller UH-12E · Mecca, CA · Accident · Minor injuries · Data collection · Final report · Sep 21, 2010 · N6053H · Substantial damage
  > The pilot's failure to maintain clearance from an obstacle while maneuvering.
- [NTSB WPR10FA440](https://openairdocs.org/ntsb/WPR10FA440.md): Hiller UH 12E · Kamiah, ID · Accident · 3 fatal · Field investigation · Final report · Aug 31, 2010 · N67264 · Substantial damage
  > In-flight impact of a passenger's metal clipboard with the helicopter’s tail rotor, which resulted in destruction of the tail rotor and subsequent loss of control of the helicopter. The original location of the clipboard and how it became free could not be…
- [NTSB ERA10LA383](https://openairdocs.org/ntsb/ERA10LA383.md): Hiller UH-12E · Holly Hill, SC · Accident · Serious injuries · Limited investigation · Final report · Jul 29, 2010 · N104HH · Substantial damage
  > Maintenance personnel's improper inspection and cleaning of the fuel nozzle, which resulted in a total loss of engine power.
- [NTSB CEN10CA362](https://openairdocs.org/ntsb/CEN10CA362.md): Hiller UH-12E · Grand Junction, CO · Accident · Minor injuries · Data collection · Final report · Jun 25, 2010 · N9754C · Substantial damage
  > The total loss of engine power for undetermined reasons.
- [NTSB WPR10LA127](https://openairdocs.org/ntsb/WPR10LA127.md): Hiller UH-12E · Los Banos, CA · Accident · No injuries · Limited investigation · Final report · Feb 2, 2010 · N36MV · Substantial damage
  > A partial loss of engine power due to a failure of the throttle interconnect hardware, which resulted in a hard landing.
- [NTSB CHI08CA252](https://openairdocs.org/ntsb/CHI08CA252.md): Hiller UH-12E · Cokato, MN · Accident · No injuries · Data collection · Final report · Aug 15, 2008 · N945HA · Substantial damage
  > The pilot did not visually identify and maintain clearance with the power lines, and the pilot's inability to maintain control of the helicopter once it contacted the power lines. Factors associated with the accident were the low altitude operations being…
- [NTSB DEN08LA071](https://openairdocs.org/ntsb/DEN08LA071.md): Hiller UH-12E · La Porte, TX · Accident · Minor injuries · Limited investigation · Final report · Apr 4, 2008 · N40289 · Substantial damage
  > The loss of tail rotor effectiveness. Contributing factors were the sudden windshift to a tailwind, and the pilot initiating a hovering turn in ground effect.

## 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" = '470' 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/470/sequence?model=4360122

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