Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Pine Knot, Kentucky 42635
Sunday, April 2, 2000 20:30 EDT
NTSB Narrative Summary Released at Completion of Accident
While in cruise flight, the flightcrew selected "GPS" on the pilot's Electronic Horizontal Situation Indicator (EHSI). The number one inverter then began to malfunction and produce lower than normal voltage. As the voltage decreased, the vertical gyroscopes began to slow down and the displays on the Electronic Attitude Display Indicators (EADI) "blacked out," without any warning from the master caution panel. Shortly thereafter, heading warning flags appeared and the compass cards locked in position on both EHSI's. Due to the decreased voltage, the motors of the directional gyroscopes drew higher-than-normal amperage, and blew their respective internal 0.75-amp fuses. When the fuses blew, the load was decreased on the number one inverter, and the voltage output increased back to normal levels; however, because of their inaccessibility, the flightcrew could not reset the fuses. Additionally, a sensing relay, pre-set to de-energize at about 40-volts AC, did not activate to illuminate an "AC FAIL" light on the master caution annunciator panel. With the normal voltage levels restored, the vertical gyroscopes began to accelerate, and approximately 8 to 10 minutes later, the EADI displays returned. The flight landed uneventfully. After the incident, the airplane manufacturer issued an Alert Service Bulletin providing instructions to replace existing low voltage sensing relays with higher accuracy relays capable of providing a warning at higher voltages and to replace the 3-amp Directional Gyros circuit breakers on the overhead circuit breaker panel, with 0.5-amp circuit breakers, enabling disconnection of power to the EHSI's prior to their internal 0.75-amp blowing.
NTSB Probable Cause Narrative
The partial failure of an inverter and the inadequate design of the electrical circuit breaker system.
Event Information
| Type of Event | Incident |
| Event Date | 4/2/2000 |
| Event Day of the Week | Sunday |
| Time of Event | 2030 |
| Event Time Zone | Eastern Daylight Time |
| Event City | PINE KNOT |
| Event State | KENTUCKY |
| Event Country | -- |
| Zipcode of the event site | 42635 |
| Event Date Year | 2000 |
| Event Date Month | 4 |
| 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 | Weather Observation Facility |
| Time of the weather observation | 2054 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 165 |
| Weather Observation Facility ID | SME |
| Elevation of weather observation facility | 927 |
| Distance of event from weather observation facility (units?) | 25 |
| Time Zone of the weather observation | EDT |
| 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) | 46 |
| Dew Point at event time (in degress fahrenheit) | 28 |
| Wind Direction (degrees magnetic) | 10 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 3 |
| 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 | 4 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 13089 |
| NTSB Notification Source | FAA FSDO-05 Cincinnati, OH |
| NTSB Notification Date | Apr 18 1999 12:00AM |
| NTSB Notification Time | 1000 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | May 1 2003 7:34AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N511WA |
| NTSB Number | NYC00IA116 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | -- |
| Damage | None |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Israel Aircraft Industries |
| Aircraft Model | 1125 |
| Aircraft Series Identifier | 1125 |
| Aircraft Serial Number | 034 |
| Certified Max Gross Weight | 23500 |
| 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 | 10 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Mar 9 2000 12:00AM |
| Airframe hours since last inspection | 55 |
| Airframe Hours | 3755 |
| ELT Installed | No |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | SSW JET LIMITED |
| Aircraft Owner Street Address | 212 E. THIRD STREET |
| Aircraft Owner City | CINCINNATI |
| Aircraft Owner State | OH |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 45226 |
| 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 | 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 | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Executive/Corporate |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | APF |
| Departure City | NAPLES |
| Departure State | FL |
| Departure Country | |
| Departure Time | 1930 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | LUK |
| Destination City | CINCINNATI |
| Destination State | OH |
| Destination Country | |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Oct 3 2001 4:45AM |
| 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 | -- |