| Date: | Monday 31 March 2003 |
| Time: | 10:00 LT |
| Type: | Hughes 369D |
| Owner/operator: | Prism Helicopters Inc. |
| Registration: | N90431 |
| MSN: | 1100833D |
| Year of manufacture: | 1980 |
| Total airframe hrs: | 11172 hours |
| Engine model: | Allison 250-C20B |
| Fatalities: | Fatalities: 0 / Occupants: 2 |
| Other fatalities: | 0 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | TYONEK, Alaska -
United States of America
|
| Phase: | Unknown |
| Nature: | Unknown |
| Departure airport: | TYONEK, AK |
| Destination airport: | |
| Investigating agency: | NTSB |
| Confidence Rating: | Accident investigation report completed and information captured |
Narrative:The commercial certificated helicopter pilot was conducting external load operations in support of seismic operations, and landed a high skid-equipped helicopter in a confined area to pick up a passenger. The landing area had knee to waist level brush. The pilot did not exit the helicopter, but waited until the passenger climbed aboard. The pilot reported that the passenger unknowingly drug a seismic cable over the toe of the left skid as he climbed into the helicopter. As the pilot was lifting the helicopter into a hover, the cable slid aft into the helicopter's external load mirror. The cable severed the mirror from the helicopter, and the mirror was propelled upward, into the main rotor blades. The mirror then struck the vertical stabilizer. A postaccident examination of the rotor system revealed that one rotor blade sustained a dent on the underside of the blade. The director of operations stated that the damaged blade was beyond allowable repair limits, and had to be replaced.
Probable Cause: The pilot's inadequate visual lookout while lifting into a hover to ensure the helicopter was clear of all objects, which resulted in separation of an external mirror that then struck and damaged a main rotor blade. Factors in the accident were the presence of a seismic cable, and high vegetation around the helicopter's takeoff spot.
Accident investigation:
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| | |
| Investigating agency: | NTSB |
| Report number: | ANC03LA038 |
| Status: | Investigation completed |
| Duration: | 6 months |
| Download report: | Final report
|
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Sources:
NTSB ANC03LA038
History of this aircraft
Other occurrences involving this aircraft
| 10 May 2024 |
N969VS |
Vertol Systems Co Inc |
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Bob Sikes Airport (CEW/KCEW), Crestview, FL |
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sub |
Revision history:
| Date/time | Contributor | Updates |
| 13-Oct-2022 16:06 |
ASN Update Bot |
Added |
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