Individually Owned: 150,657
Corporate Owned: 137,281
Blue Grass Airport
Aircraft Accident/Incident Report
Lexington, Kentucky 40501
Friday, February 5, 1999 10:00 EDT
NTSB Narrative Summary Released at Completion of Accident
The during descent for landing, the airplane's right engine, a TPE331-14B, experienced an uncontained gearcase failure. Disassembly of the engine revealed that the gearcase was ruptured in the 1st bull gear's plane of rotation and that the 1st bull gear had a 90 degree arc of the rim and gear teeth separated. Metallurgical examination of the 1st bull gear revealed a fatigue fracture that had originated in the gear's bore splines. The fatigue originated in area where the spline thickness was significantly reduced by indentations on the pressure surface of the splines. Review of the engine's overhaul manual revealed a tie-rod was used to provide a clamping force between the spur gear and 1st bull gear. The assembly procedures required that the tie-rod be stretched with a load of 22,000 pounds, and then secured with a nut that was hand-tightened. During disassembly of the gearcase, it was not possible to determine the amount of stretch on the tie-rod, or the breakaway torque on the retaining nut. Maintenance records revealed that the gearcase was disassembled, and reassembled during repairs, which were performed by engine manufacturer.
NTSB Probable Cause Narrative
Improper assembly of the engine gearcase by the manufacturer, which resulted in an uncontained failure of the 1st bull gear.
Event Information
| Type of Event | Incident |
| Event Date | 2/5/1999 |
| Event Day of the Week | Friday |
| Time of Event | 1000 |
| Event Time Zone | Eastern Daylight Time |
| Event City | LEXINGTON |
| Event State | KENTUCKY |
| Event Country | -- |
| Zipcode of the event site | 40501 |
| Event Date Year | 1999 |
| Event Date Month | 2 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | |
| Event Location Longitude | |
| Event Location Airport | BLUE GRASS |
| Event Location Nearest Airport ID | LEX |
| Indicates whether the acc/inc occurred off or on an airport | Unknown |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | 980 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 954 Eastern Standard Time |
| Direction of event from weather observation facility (degrees) | 0 |
| Weather Observation Facility ID | LEX |
| Elevation of weather observation facility | 980 |
| Distance of event from weather observation facility (units?) | 0 |
| Time Zone of the weather observation | EST |
| Lighting Conditions | Day |
| 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) | 2 |
| Dew Point at event time (in degress fahrenheit) | -4 |
| Wind Direction (degrees magnetic) | 150 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 9 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 30 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | Unknown |
| 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 | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 5006 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Feb 10 1999 12:00AM |
| NTSB Notification Time | 1530 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 12 2000 11:24AM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N37KW |
| NTSB Number | NYC99IA056 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | -- |
| Damage | Minor |
| Aircraft Fire | In-flight |
| Aircraft Explosion | In-flight |
| Aircraft Manufacturer's Full Name | Piper |
| Aircraft Model | PA42-1000 |
| Aircraft Series Identifier | PA42-1000 |
| Aircraft Serial Number | 425527039 |
| Certified Max Gross Weight | 12100 |
| Aircraft Category | Airplane |
| 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 | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Nov 18 1998 12:00AM |
| Airframe hours since last inspection | 90 |
| Airframe Hours | 3694 |
| ELT Installed | Yes |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | CUMBERLAND MANGMNT & HOLDINGS |
| Aircraft Owner Street Address | 30 OLD RUDNICK LANE |
| Aircraft Owner City | DOVER |
| Aircraft Owner State | DE |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 19901 |
| 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 | |
| Owner has at least one certificate | None |
| 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 | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | ILG |
| Departure City | WILMINGTON |
| Departure State | DE |
| Departure Country | |
| Departure Time | 800 |
| Departure Time Zone | EST |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | LEX |
| Destination City | |
| Destination State | |
| Destination Country | |
| Specific Phase of Flight | Descent |
| 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 | 22 |
| Runway Length | 7003 |
| Runway Width | 153 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |