Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Pahoa, Hawaii 96778
Friday, January 21, 2005 15:30 HST
NTSB Narrative Summary Released at Completion of Accident
The helicopter impacted small trees during an autorotational landing that was preceded by the in-flight separation of a tail rotor blade abrasion strip. According to the pilot, the helicopter developed a "sudden vibration in the tail rotor pedals followed immediately by a loud 'crack' or 'snap', and then an extremely loud banging noise and a sharp vibration in both airframe as well as the tail rotor pedals." The pilot made an off-airport autorotational landing to a clearing, but during the landing flare, the tail section snagged a tree. Post-accident examination of the tail rotor blades revealed that the leading edge abrasion strip debonded from one of the blades. Based on the surface finish, the debonding was most probably an adhesive failure at the interface with the abrasion strip. The cause of the bond failure is unknown, but could be the result of in-service conditions, a production problem, or undetected impact damage. The adhesive is the primary means of holding the strip to the blade, but there are also two rivets on the inboard end of the blade that serve as a secondary securing method. The abrasion strip fractured at the outboard rivet and the fracture surface revealed evidence of fatigue cracking indicating that the abrasion strip was completely debonded for a period of time. In addition, dark sooty deposits were visible in the bond area on both sides of the blade. Maintenance records indicated that the helicopter underwent a 100-hour inspection approximately 62 hours prior to the accident. The inspection calls for a visual examination of the tail rotor blades to ensure no separation of the bond around the edges or at the tip end of the blade exist. The inspection process calls for a dye-penetrant inspection or tap test only if a debond is suspected. However, detection of the debond during the visual only 100-hour inspection would depend on whether the separation intersected on the strip edges. The preflight examination procedures called for the pilot to visually examine the tail rotor blades to ensure there is no debonding along the abrasion strip-to-airfoil bond line. The pilot reported that he inspected the abrasion strip prior to the accident flight, but did not notice any evidence of an abrasion strip debond. The blade accumulated 2,379.7 total hours of operation, and 1,820.6 hours since its last overhaul.
NTSB Probable Cause Narrative
the in-flight separation of the tail rotor blade abrasion strip due to a degraded adhesive bond and fatigue fracture of the metallic abrasion strip. The ultimate cause for the degraded bond is unknown.
Event Information
| Type of Event | Accident |
| Event Date | 1/21/2005 |
| Event Day of the Week | Friday |
| Time of Event | 1530 |
| Event Time Zone | Hawaii Standard Time |
| Event City | Pahoa |
| Event State | HAWAII |
| Event Country | -- |
| Zipcode of the event site | 96778 |
| Event Date Year | 2005 |
| Event Date Month | 1 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 192721N |
| Event Location Longitude | 1150117W |
| 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 | Weather Observation Facility |
| Time of the weather observation | 1453 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | 285 |
| Weather Observation Facility ID | KOA |
| Elevation of weather observation facility | -- |
| Distance of event from weather observation facility (units?) | 45 |
| Time Zone of the weather observation | PST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 4500 |
| Lowest Non-Ceiling Height | 3600 |
| Sky/Lowest/Cloud Conditions | Scattered |
| Sky Condition for Lowest Ceiling | Overcast |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 27 |
| Dew Point at event time (in degress fahrenheit) | 21 |
| Wind Direction (degrees magnetic) | 250 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 7 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.84 |
| 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 | 5 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 19550 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Feb 3 2005 12:00AM |
| NTSB Notification Time | 830 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Apr 25 2006 11:00AM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Federql Aviation Administration Honolulu FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N142MK |
| NTSB Number | LAX05LA074 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 135: Air Taxi & Commuter |
| Type of Flight Plan filed | Company VFR |
| Flight plan Was Activated? | Yes |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | MDHI |
| Aircraft Model | 369E |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 187E |
| Certified Max Gross Weight | 3000 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | -- |
| 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 | Jan 1 2005 12:00AM |
| Airframe hours since last inspection | 65.2 |
| Airframe Hours | 7592.6 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Schuman Aviation Co. Ltd |
| Aircraft Owner Street Address | 1534 Uluhaku Pl |
| Aircraft Owner City | Kailua |
| Aircraft Owner State | HI |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 96734 |
| Operator is an individual? | No |
| Operator Name | K & S Helicopters, Inc. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | P.O. Box 5371 |
| Operator City | Kailua-Kona |
| Operator State | HI |
| Operator Country | USA |
| Operator Zip code | 96745 |
| Operator Code | K2DA |
| 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 | No |
| Departure Airport Code | ITO |
| Departure City | Hilo |
| Departure State | HI |
| Departure Country | USA |
| Departure Time | 1500 |
| Departure Time Zone | HST |
| 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 | Emergency descent/landing |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Feb 7 2006 4:10PM |
| User who most recently changed record | COOS |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | Yes |
| Air Medical Flight | No |
| Medical Flight | -- |