Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Hana, Hawaii 96713
Tuesady, November 12, 1996 14:50 HST
NTSB Narrative Summary Released at Completion of Accident
During flight, the pilot heard a loud noise from the engine compartment, accompanied by the engine out light & horn. He entered an autorotation, & the helicopter rolled over during touchdown on mountainous terrain. Disassembly of the engine revealed the forward splines of the Spur Adapter Gearshaft (SAG), which connected the compressor & turbine module shafts, had fractured, & the compressor module was disconnected from the turbine section. The SAG retaining ring was found to have machined into the compressor impeller, which allowed the SAG to shift aft. Aft movement of the SAG then resulted in heavy wear on the splines of both the Compressor Adapter Coupling (CAC) & the SAG, which resulted in a fatigue failure of the SAG splines. The CAC & impeller were of an old configuration. Allison Commercial Engine Bulletin 1325 recommended replacement of the old CAG, SAG, impellers, & retaining rings with models of a newer design to 'improve spline wear characteristics.' Allison engineers opined that the typical retaining ring to impeller machining was due to the same retaining ring being returned to the engine during overhaul, though evidence of this was not apparent in the engine examination.
NTSB Probable Cause Narrative
subsequent failure of the spur adapter gearshaft (SAG), after 'retaining ring to compressor impeller machining' occurred and allowed the SAG to shift aft. The mechanism which induced the ring to impeller machining was not determined. Mountainous terrain in the emergency landing area was a related factor.
Event Information
| Type of Event | Accident |
| Event Date | 11/12/1996 |
| Event Day of the Week | Tuesday |
| Time of Event | 1450 |
| Event Time Zone | Hawaii Standard Time |
| Event City | HANA |
| Event State | HAWAII |
| Event Country | -- |
| Zipcode of the event site | 96713 |
| Event Date Year | 1996 |
| Event Date Month | 11 |
| 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 | Unknown |
| Investigator's weather source | Pilot |
| Time of the weather observation | 0 |
| Direction of event from weather observation facility (degrees) | 0 |
| Weather Observation Facility ID | |
| Elevation of weather observation facility | 0 |
| Distance of event from weather observation facility (units?) | 0 |
| Time Zone of the weather observation | |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 3000 |
| Lowest Non-Ceiling Height | 0 |
| Sky/Lowest/Cloud Conditions | Unknown |
| Sky Condition for Lowest Ceiling | Overcast |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 20 |
| Air Temperature at event time (in degrees celsius) | 20 |
| Dew Point at event time (in degress fahrenheit) | -- |
| Wind Direction (degrees magnetic) | 0 |
| Variable Wind Indicator | Variable |
| Wind Speed (knots) | 5 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 29 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | Light |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 5 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 1733 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Nov 15 1996 12:00AM |
| NTSB Notification Time | 1100 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 8 2000 10:27AM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N8625F |
| NTSB Number | LAX97LA039 |
| 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 | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | McDonnell Douglas |
| Aircraft Model | 369D |
| Aircraft Series Identifier | 369D |
| Aircraft Serial Number | 470111D |
| 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 | Oct 12 1996 12:00AM |
| Airframe hours since last inspection | 79 |
| Airframe Hours | 17998 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | STEVEN H. ALEXANDER |
| Aircraft Owner Street Address | 355 HUKILIKE STREET, #211 |
| Aircraft Owner City | KAHULUI |
| Aircraft Owner State | HI |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 96732 |
| Operator is an individual? | -- |
| Operator Name | ALIKA AVIATION |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | HANGER 108, KAHULUI HELIPORT |
| Operator City | KAHULUI |
| Operator State | HI |
| Operator Country | |
| Operator Zip code | 96732 |
| Operator Code | DNWA |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | Unknown |
| 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 | KAHULUI |
| Departure State | HI |
| Departure Country | |
| Departure Time | 1430 |
| 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 landing |
| 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 | Yes |
| Air Medical Flight | No |
| Medical Flight | -- |