Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Lanai City,Maui, Hawaii 96763
Wednesday, May 20, 1998 5:00 HST
NTSB Narrative Summary Released at Completion of Accident
The engine chip light illuminated during cruise and about 10 seconds later the engine out light flickered and then fully illuminated. As the pilot was performing an autorotation he and his passengers heard a loud bang, the helicopter landed on uneven terrain, and subsequently rolled over onto its side. A postcrash fire consumed the helicopter. The third turbine wheel was not located. The fourth turbine wheel was found remote from the helicopter with missing airfoils. In the 5 months prior to the accident, the power turbine had been removed for inspection and repaired several times due to one instance of an N2 lockup and chipped drive splines, and several instances of engine chip light illuminations with high temperatures and turbine rub. In each case, the plugs were removed, inspected per the manufacturer's maintenance manuals, and the oil system flushed. The day before the accident the engine chip light illuminated and the operator found a pasty substance on the chip detector. The chip detector was inspected in accordance with the manufacturer's maintenance manuals and the helicopter was then returned to service. Postaccident disassembly of the engine revealed an oil starvation failure of the No. 5 bearing and a subsequent failure of the No. 3 bearing due to a transfer of the axial loads normally carried by the No. 5 bearing. After the loss of the No. 5 bearing, there was an uncontained overspeed failure of the power turbine rotor to loss of power turbine gear train tooth engagement. Metal debris was encased on the tip of one of the chip detectors. The oil delivery tube that supplies oil to the No. 5 bearing was not recovered and was assumed to have been consumed in the postimpact fire.
NTSB Probable Cause Narrative
An oil starvation failure of the number 5 bearing for undetermined reasons.
Event Information
| Type of Event | Accident |
| Event Date | 5/20/1998 |
| Event Day of the Week | Wednesday |
| Time of Event | 500 |
| Event Time Zone | Hawaii Standard Time |
| Event City | LANAI CITY,MAUI |
| Event State | HAWAII |
| Event Country | -- |
| Zipcode of the event site | 96763 |
| Event Date Year | 1998 |
| Event Date Month | 5 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | |
| Event Location Longitude | |
| 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 | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 500 Hawaii Standard Time |
| Direction of event from weather observation facility (degrees) | 180 |
| Weather Observation Facility ID | LNY |
| Elevation of weather observation facility | 1308 |
| Distance of event from weather observation facility (units?) | 5 |
| Time Zone of the weather observation | HST |
| Lighting Conditions | Night/Dark |
| Lowest Ceiling Height | 0 |
| Lowest Non-Ceiling Height | 0 |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | -- |
| Dew Point at event time (in degress fahrenheit) | -- |
| Wind Direction (degrees magnetic) | 60 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 15 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | -- |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | Minor |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | 4 |
| Injury Total Serious | -- |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 1816 |
| NTSB Notification Source | -- |
| NTSB Notification Date | May 20 1998 12:00AM |
| NTSB Notification Time | 1040 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 11 2000 11:22AM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N112HD |
| NTSB Number | LAX98LA166 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 135: Air Taxi & Commuter |
| Type of Flight Plan filed | Company VFR |
| Flight plan Was Activated? | -- |
| Damage | Destroyed |
| Aircraft Fire | In-flight |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | McDonnell Douglas |
| Aircraft Model | 520N |
| Aircraft Series Identifier | 520N |
| Aircraft Serial Number | LN008 |
| Certified Max Gross Weight | 3350 |
| 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 | May 7 1998 12:00AM |
| Airframe hours since last inspection | 19 |
| Airframe Hours | 3861 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | WINDWARD AVIATION INC. |
| Aircraft Owner Street Address | 333 DAIRY RD. SUITE 103 |
| Aircraft Owner City | KAHULUI |
| Aircraft Owner State | HI |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 96732 |
| Operator is an individual? | -- |
| Operator Name | |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | |
| Operator City | |
| Operator State | |
| Operator Country | |
| Operator Zip code | |
| Operator Code | WVXA |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | External Load |
| 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) | Unknown |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | OGG |
| Departure City | MAUI |
| Departure State | HI |
| Departure Country | |
| Departure Time | 435 |
| Departure Time Zone | HST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | LNY |
| Destination City | LANAI CITY |
| Destination State | HI |
| Destination Country | |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jan 2 2001 10:34AM |
| User who most recently changed record | dbo |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | 0 |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |