# NTSB Accident CHI89DEP04
> **HILLER UH-12E** · 1989-05-22 · WATERFORD, WI, USA · NONE
## Event
- **NTSB number:** CHI89DEP04
- **Event ID:** 20001213X28258
- **Type:** Accident
- **Date:** 1989-05-22
- **Location:** WATERFORD, WI, USA
- **Coordinates:** 42.759864, -88.209365
## Injuries
- **Highest injury:** NONE
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 1
- **Total aboard:** 1
## Aircraft
- **Make:** HILLER
- **Model:** UH-12E
- **Registration:** N3829
- **FAR Part:** 091
- **Engines:** 1
- **Damage:** SUBS
## Conditions
- **Light:** DAYL
- **Weather:** VMC
## Probable cause

THE PILOT'S INABILITY TO MAINTAIN CONTROL DURING AN AUTOROTATIONAL LANDING ATTEMPT FOLLOWING THE FAILURE OF THE MAIN ROTOR DRIVE TRAIN TORSIONAL COUPLING.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=CHI89DEP04) · AI Analytics · CC0 1.0*