Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Valdez, Alaska 99686
Monday, April 7, 2003 11:15 AKD
NTSB Narrative Summary Released at Completion of Accident
The commercial certificated pilot was landing a wheel/ski-equipped helicopter at a remote spot on a snow-covered ridgeline, about 4,200 feet msl. The pilot said that as the landing gear wheels touched the ridgeline, the helicopter started to shake in ground resonance. He decided to lift off, and the vibration became severe. The pilot said he lowered the collective pitch control and began a descent toward lower terrain. During the descent, the pilot said the helicopter nearly became uncontrollable until he heard one of the main rotor spacing cables snap. The previous 3 per revolution vibrations smoothed out, and became a 1 per revolution vibration. The pilot landed the helicopter on a glacier moraine. After landing, the pilot discovered that the broken spacing cable damaged the inboard trailing edge of one main rotor blade. The tail boom assembly was buckled and torn at the bottom attach point to the fuselage. A postaccident examination of the helicopter revealed that an attaching bolt, used to secure the yellow blade spacing cable to the red blade rotor grip fitting, was missing and the yellow blade damper was compressed. The missing bolt from the spacing cable fitting has a hollow shaft design which enables the bolt to shear when excessively loaded. Under extreme unbalanced conditions, the separation of the spacing cable permits an unbalanced rotor blade additional horizontal movement. Following the accident, the main rotor dampers were sent to an overhaul facility by the operator's insurance company. The overhaul facility reported that examination of the dampers did not reveal any observed malfunction.
NTSB Probable Cause Narrative
The pilot's encounter with a ground resonance condition during the landing touchdown, which resulted in the shearing of a main rotor spacing cable bolt, and buckling of the tail boom.
Event Information
| Type of Event | Accident |
| Event Date | 4/7/2003 |
| Event Day of the Week | Monday |
| Time of Event | 1115 |
| Event Time Zone | -- |
| Event City | VALDEZ |
| Event State | ALASKA |
| Event Country | -- |
| Zipcode of the event site | 99686 |
| Event Date Year | 2003 |
| Event Date Month | 4 |
| MidAir Collision Indicator | -- |
| On Ground Collision occurred ? | -- |
| Event Location Latitude | 611118N |
| Event Location Longitude | 1452041W |
| 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 | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1115 Atlantic Daylight Time |
| Direction of event from weather observation facility (degrees) | 245 |
| Weather Observation Facility ID | PAVD |
| Elevation of weather observation facility | 120 |
| Distance of event from weather observation facility (units?) | 26 |
| Time Zone of the weather observation | ADT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 7500 |
| Lowest Non-Ceiling Height | 4300 |
| Sky/Lowest/Cloud Conditions | Few |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 2 |
| Dew Point at event time (in degress fahrenheit) | -11 |
| Wind Direction (degrees magnetic) | 115 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 9 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.32 |
| 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 | 6 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 14507 |
| NTSB Notification Source | FAA REGIONAL OPERATIONS CENTER |
| NTSB Notification Date | Apr 7 2003 12:00AM |
| NTSB Notification Time | 1452 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Dec 30 2003 8:55AM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | FAA-AL-ANC FSDO 03 |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N119PH |
| NTSB Number | ANC03LA042 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 135: Air Taxi & Commuter |
| 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 | Aerospatiale |
| Aircraft Model | SA-319B |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 2119 |
| Certified Max Gross Weight | 4960 |
| 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 | 7 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Conditional |
| Date of Last Inspection | Mar 30 2003 12:00AM |
| Airframe hours since last inspection | 21 |
| Airframe Hours | 4611 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | AIRBORNE TURBINE INC. |
| Aircraft Owner Street Address | 903 AIRPORT DR., SUITE 2 |
| Aircraft Owner City | SAN LUIS OBISPO |
| Aircraft Owner State | CA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 93401 |
| Operator is an individual? | No |
| Operator Name | PERFORMANCE HELICOPTERS LLC. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | PMB216 1830 E. PARKS HIGHWAY |
| Operator City | WASILLA |
| Operator State | AK |
| Operator Country | USA |
| Operator Zip code | 99654 |
| Operator Code | PYFC |
| Owner has at least one certificate | -- |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | Non-scheduled |
| Indicates Domestic or International Flight | Domestic |
| Operator carrying Pax/Cargo/Mail | Passenger Only |
| Type of Flying (Per_Bus / Primary) | -- |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | -- |
| Departure City | VALDEZQ |
| Departure State | AK |
| Departure Country | USA |
| Departure Time | 1115 |
| Departure Time Zone | ADT |
| 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 | Landing - flare/touchdown |
| Report sent to ICAO? | Yes |
| Evacuation occurred | -- |
| Date of most recent change to record | Oct 23 2003 4:05PM |
| 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 | -- |