# NTSB CHI90DTG02: Hiller UH-12-E, N133HA, Garrison, ND, August 4, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: August 4, 1990, 09:45 local (15:45 UTC)
- Place: Garrison, ND
- Coordinates: 47.649581, -101.42015 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.6496&lon=-101.4202&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report December 14, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14508
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI90DTG02
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14508/pdf
- Page: https://openairdocs.org/ntsb/CHI90DTG02

## Probable cause

THE FAILURE OF THE HELICOPTER TAIL ROTOR CONTROL CABLE. A FACTOR RELATED TO THE ACCIDENT WAS THE CHAFING OF THE TAIL ROTOR CONTROL CABLE.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, takeoff
  - rotorcraft flight control,tail rotor cable - failure,total (cause)
  - directional control - not possible, pilot in command (cause)
  - rotorcraft flight control,tail rotor cable - chafed (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

DURING THE TAKEOFF TRANSITION TO FORWARD FLIGHT THE HELICOPTER PILOT FELT THE LEFT ANTITORQUE PEDAL GO TO THE FLOOR, AND THE HELICOPTER BEGAN TO ROTATE UNCONTROLLED. THE PILOT MANEUVERED THE HELICOPTER TO A CLEAR AREA AND ATTEMPTED TO LAND. UNCONTROLLED CONTACT WAS MADE WITH THE TERRAIN. THE INVESTIGATION REVEALED THAT THE LEFT TAIL ROTOR CONTROL CABLE HAD FAILED DUE TO OVERLOAD IN AN AREA WHICH HAD BEEN SUBJECT TO MECHANICAL ABRASION.

## Aircraft

- Registration: [N133HA](https://openairdocs.org/aircraft/N133HA), registered now, S/N HA3033, built 1976 (OpenAirDocs)
- Reported make and model: HILLER UH-12-E
- Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs)
- Registry engine: [Lycoming VO-540 series](https://openairdocs.org/engine/lycoming-vo-540-series) (registry code 41534, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 3033
- Airframe hours: 1328
- Engines: LYCOMING VO-540-C2A 305 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Morten, Shawn B., doing business as N/A
- Registered owner: Shawn B Morten
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, May 18, 1990, 258 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 29; commercial, flight instructor; airplane ratings: single-engine land; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 5,000 total, 700 in this make and model, 4,700 as pilot in command, 355 in the last 90 days, 177 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 360° at 7 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 75 °F, dew point -0 °F
- Altimeter: 30.00 inHg
- Observed at: BIS, 40 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19900804030089A](https://openairdocs.org/incident/19900804030089A), Aug 4, 1990: Hiller UH12E, Garrison, ND, Substantial damage. Tail rotor control cable broke on lift off. Caused loss of control and crash.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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