Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Tyonek, Alaska 99682
Monday, March 31, 2003 10:00 AST
NTSB Narrative Summary Released at Completion of Accident
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.
NTSB Probable Cause Narrative
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.
Event Information
| Type of Event | Accident |
| Event Date | 3/31/2003 |
| Event Day of the Week | Monday |
| Time of Event | 1000 |
| Event Time Zone | Atlantic Standard Time |
| Event City | TYONEK |
| Event State | ALASKA |
| Event Country | -- |
| Zipcode of the event site | 99682 |
| Event Date Year | 2003 |
| Event Date Month | 3 |
| MidAir Collision Indicator | -- |
| On Ground Collision occurred ? | -- |
| Event Location Latitude | 610100N |
| Event Location Longitude | 1512656W |
| Event Location Airport | -- |
| Event Location Nearest Airport ID | -- |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Pilot |
| Time of the weather observation | |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | -- |
| Elevation of weather observation facility | -- |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | -- |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 30 |
| Air Temperature at event time (in degrees celsius) | -7 |
| Dew Point at event time (in degress fahrenheit) | -- |
| Wind Direction (degrees magnetic) | 200 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 5 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | -- |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 13871 |
| NTSB Notification Source | PRISM HELICOPTERS INC. |
| NTSB Notification Date | Apr 4 2003 12:00AM |
| NTSB Notification Time | 950 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Sep 30 2003 9:55AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | FAA-AL-ANC FSDO 03 |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N90431 |
| NTSB Number | ANC03LA038 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 133: Rotorcraft Ext. Load |
| Type of Flight Plan filed | Company VFR |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Hughes |
| Aircraft Model | 369D |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 1100833D |
| Certified Max Gross Weight | 3000 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 5 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Feb 27 2003 12:00AM |
| Airframe hours since last inspection | 67 |
| Airframe Hours | 11172 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | WELLS FARGO BANK NW, TRUSTEE |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | SALT LAKE |
| Aircraft Owner State | UT |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | -- |
| Operator is an individual? | No |
| Operator Name | PRISM HELICOPTERS INC. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | P.O. BOX 872807 |
| Operator City | WASILLA |
| Operator State | AK |
| Operator Country | USA |
| Operator Zip code | 99687 |
| Operator Code | EOOA |
| Owner has at least one certificate | -- |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | External Load |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Other Work Use |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | -- |
| Departure City | TYONEK |
| Departure State | AK |
| Departure Country | USA |
| Departure Time | 1000 |
| Departure Time Zone | AST |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | -- |
| Destination City | -- |
| Destination State | -- |
| Destination Country | -- |
| Specific Phase of Flight | Hover |
| Report sent to ICAO? | No |
| Evacuation occurred | -- |
| Date of most recent change to record | Jul 2 2003 7:41PM |
| User who most recently changed record | PETL |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | -- |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |