Accident Hughes 369D N90431, Monday 31 March 2003
ASN logo
 

Date:Monday 31 March 2003
Time:10:00 LT
Type:Silhouette image of generic H500 model; specific model in this crash may look slightly different    
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:
cover
  
Investigating agency: NTSB
Report number: ANC03LA038
Status: Investigation completed
Duration: 6 months
Download report: Final report

Sources:

NTSB ANC03LA038

History of this aircraft

Other occurrences involving this aircraft

10 May 2024 N969VS Vertol Systems Co Inc 0 Bob Sikes Airport (CEW/KCEW), Crestview, FL sub

Revision history:

Date/timeContributorUpdates
13-Oct-2022 16:06 ASN Update Bot Added

Corrections or additions? ... Edit this accident description

The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2025 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314
www.FlightSafety.org