# NTSB DEN08LA071: Hiller UH-12E, N40289, La Porte, TX, April 4, 2008

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: April 4, 2008, 15:03 local (20:03 UTC)
- Place: La Porte, TX
- Coordinates: 29.671388, -95.073608
- Nearby events: https://openairdocs.org/map.md?lat=29.6714&lon=-95.0736&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Defining event: [Maneuvering-hover: Loss of control in flight](https://openairdocs.org/ntsb-events/240)
- Highest injury: Minor injuries
- Injuries: 1 minor, 1 uninjured
- Status: Completed, report August 28, 2008
- Report: Approved by Office Director
- Parties: Houston, Texas
- NTSB case key (mKey): 67780
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN08LA071
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67780/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=67780
- Page: https://openairdocs.org/ntsb/DEN08LA071

## Probable cause

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.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Wind: sudden wind shift](https://openairdocs.org/ntsb-findings/03034010): Environmental issues › Conditions/weather/phenomena · Not specified (probable cause); cases with it: [Hiller UH-12E, 1 case](https://openairdocs.org/ntsb-findings/03034010/cases.md?model=4360122), [All aircraft, 114 cases](https://openairdocs.org/ntsb-findings/03034010/cases.md)
- [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Not specified (probable cause); cases with it: [Hiller UH-12E, 1 case](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=4360122), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md)
- [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Hiller UH-12E, 3 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=4360122), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md)
- [Runway/land/takeoff/taxi surface: glassy surface](https://openairdocs.org/ntsb-findings/03023025): Environmental issues › Physical environment · Not specified; cases with it: [Hiller UH-12E, 1 case](https://openairdocs.org/ntsb-findings/03023025/cases.md?model=4360122), [All aircraft, 25 cases](https://openairdocs.org/ntsb-findings/03023025/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Maneuvering: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Hiller UH-12E, 1 case](https://openairdocs.org/ntsb-events/400/sequence.md?model=4360122), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md)
- [Maneuvering-hover: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Hiller UH-12E, 7 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=4360122), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md)
- [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Hiller UH-12E, 14 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=4360122), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The pilot was test flying the helicopter after maintenance. He did two "quick stop" maneuvers into the wind. After completing the quick stop maneuver, and while in a 5-foot hover, he initiated a slow pedal turn to the left to return to the hangar. As he began the turn, he noticed "a loss of control effectiveness" and he attempted to set the helicopter down. Before he could regain control, the helicopter "slammed" into the ground. The pilot said it had begun to rain, and after he exited the helicopter, he noticed the wind sock had shifted 180 degrees. The tail boom was severed and the main rotor blades were destroyed.

## Factual narrative

On April 4, 2008, at 1503 central daylight time, a Hiller UH-12E, N40289, registered to and operated by Ascent Aviation, was substantially damaged when it struck the ground while maneuvering and rolled over at La Porte Municipal Airport (T14), La Porte, Texas. Visual meteorological conditions prevailed at the time of the accident. The test flight was being conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The airline transport certificated pilot received minor injuries, and his pilot certificated passenger was not injured. The local flight originated at T41 approximately 10 minutes before the accident.

According to the pilot's accident report, he was test flying the helicopter after performing some maintenance that had been requested by its new owner. He performed two "quick stop" maneuvers into the wind. After completing the quick stop maneuver and while in a 5-foot hover, he initiated a slow pedal turn to the left to return to the hangar. As he began the turn, he noticed "a loss of control effectiveness" and he attempted to set the helicopter down. Before he could regain control, the helicopter "slammed" into the ground. The pilot said it had begun to rain and after he exited the helicopter, he noticed the wind sock had shifted 180 degrees. The tail boom was severed and the main rotor blades were destroyed.

## Aircraft

- Registration: [N40289](https://openairdocs.org/deregistered/N40289-2012-11-15), registration cancelled 2012-11-15, S/N 5096, built 1979 (OpenAirDocs)
- Reported make and model: Hiller UH-12E
- 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: 5096
- Airframe hours: 2216
- Engines: Lycoming VO-540-C2A 305 horsepower reciprocating
- Damage: Substantial damage
- Flight: Flight test, Part 91
- Operator: Paul Legris
- Registered owner: Ascent Aviation
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, January 1, 2008
- Departed: T41, La Porte, TX
- Destination: T41, La Porte, TX
- Airport: T41, La Porte Municipal

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Flight instructor; age 52; injuries: serious; commercial, flight instructor, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review May 1, 2007; seat: left; flight hours: 20,000 total, 700 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 330° at 13 knots, gusting 21
- Visibility: 10 statute miles
- Lowest ceiling: 800 ft broken
- Temperature: 64 °F, dew point 61 °F
- Altimeter: 29.81 inHg

## 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 20080404832169A](https://openairdocs.org/incident/20080404832169A), Apr 4, 2008: Hiller UH12E, La Porte, TX, Substantial damage. (-23) Aircraft control was lost while doing hover practice in the grassy area at the approach end of runway 05 at the La Porte (T41) airport. Pilot stated he…

## Other investigations on N40289 (1)

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.

- [NTSB ATL80FIJ02](https://openairdocs.org/ntsb/ATL80FIJ02), May 12, 1980: Hiller Acft UH-12E (N40289), Oak Hill, WV, substantial damage

## Docket (3 files)

The files NTSB released with the investigation on July 21, 2008, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=67780. 1.2 MB in all.

- Supplemental E, Second Pilot Information (item 1, .PDF, 117 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40297155&FileExtension=.PDF&FileName=Supplemental%20E,%20Second%20Pilot%20Information-Master.PDF
- NTSB Form 6120.1, Pilot Operator Accident Report (item 2, .PDF, 783 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40297157&FileExtension=.PDF&FileName=NTSB%20Form%206120.1,%20Pilot%20Operator%20Accident%20Report-Redacted.PDF
- FAA Form 8020-23 (item 3, .PDF, 350 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40297181&FileExtension=.PDF&FileName=FAA%20Form%208020-23-Redacted.PDF

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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