Individually Owned: 150,657
Corporate Owned: 137,281
Piedmont Triad International Airport
Aircraft Accident/Incident Report
Greensboro, North Carolina
Tuesady, August 8, 2000 15:44 EDT
NTSB Narrative Summary Released at Completion of Accident
Examination of the area of the fire origin revealed that relay R2-53, the left heat exchanger cooling fan relay, was severely heat damaged, as were R2-54 and the other relays in this area. However, the R2-53 relay also exhibited loose terminal studs and several holes that had burned through the relay housing that the other relays did not exhibit. The wire bundles that run immediately below the left and right heat exchanger cooling fans and the ground service tie relays exhibited heat damage to the wire insulation, with the greatest damage located just below the R2-53 relay. The unique damage observed on the R2-53 relay and the wire damage directly below it indicates that fire initiation was caused by an internal failure of the R2-53 relay. Disassembly of the relay revealed that the R2-53 relay had been repaired but not to the manufacturer's standards. According to the manufacturer, the damage to the relay housing was consistent with a phase-to-phase arc between terminals A2 and B2 of the relay. During the on-scene portion of the investigation, three of the four circuit breakers in the left heat exchanger cooling fan were found in the tripped position. To determine why only three of the four circuit breakers tripped, all four were submitted to the Materials Integrity Branch at Wright-Patterson Air Force Base, Dayton, Ohio, for further examination. The circuit breakers were visually examined and were subjected to an insulation resistance measurement, a contact resistance test, a voltage drop test, and a calibration test (which measured minimum and maximum ultimate trip times). Testing and examination determined that the circuit breaker that did not trip exhibited no anomalies that would prevent normal operation, met all specifications required for the selected tests, and operated properly during the calibration test. Although this circuit breaker appeared to have functioned properly during testing, the lab report noted that, as a thermal device, the circuit breaker is designed to trip when a sustained current overload exists and that it is possible during the event that intermittent arcing or a resistive short occurred or that the circuit opened before the breaker reached a temperature sufficient to trip the device.
NTSB Probable Cause Narrative
A phase-to-phase arc in the left heat exchanger cooling fan relay, which ignited the surrounding wire insulation and other combustible materials within the electrical power center panel. Contributing to the left heat exchanger fan relay malfunction was the unauthorized repair that was not to the manufacturer's standards and the circuit breakers' failure to recognize an arc-fault.
Event Information
| Type of Event | Accident |
| Event Date | 8/8/2000 |
| Event Day of the Week | Tuesday |
| Time of Event | 1544 |
| Event Time Zone | Eastern Daylight Time |
| Event City | GREENSBORO |
| Event State | NORTH CAROLINA |
| Event Country | -- |
| Zipcode of the event site | -- |
| Event Date Year | 2000 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | -- |
| Event Location Longitude | -- |
| Event Location Airport | PIEDMONT TRIAD INTERNATIONAL |
| Event Location Nearest Airport ID | GSO |
| 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 | |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | -- |
| Elevation of weather observation facility | -- |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | -- |
| Lighting Conditions | Not Reported |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| 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) | 0 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | Calm |
| Wind Gust Indicator | Unknown |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | -- |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| 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 | 13 |
| Injury Total None | 50 |
| Injury Total Serious | -- |
| Injury Total All | 13 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 13534 |
| NTSB Notification Source | Comm Center |
| NTSB Notification Date | Aug 8 2000 12:00AM |
| NTSB Notification Time | 1700 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Mar 3 2004 3:25PM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N838AT |
| NTSB Number | DCA00MA079 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | In-flight |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Douglas |
| Aircraft Model | DC-9-32 |
| Aircraft Series Identifier | DC-9-32 |
| Aircraft Serial Number | -- |
| Certified Max Gross Weight | -- |
| 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 | 119 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Unknown |
| Date of Last Inspection | -- |
| Airframe hours since last inspection | -- |
| Airframe Hours | -- |
| ELT Installed | Unknown |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | -- |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | -- |
| Aircraft Owner State | -- |
| Aircraft Owner Country | -- |
| Aircraft Owner Zipcode | -- |
| Operator is an individual? | No |
| Operator Name | AIRTRAN AIRLINES INC |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 9955 AIR TRAN BLVD |
| Operator City | ORLANDO |
| Operator State | FL |
| Operator Country | -- |
| Operator Zip code | 32827 |
| Operator Code | VJ6A |
| 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 | 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 | -- |
| Departure Point Same as Event | Yes |
| Departure Airport Code | -- |
| Departure City | -- |
| Departure State | -- |
| Departure Country | -- |
| Departure Time | 0 |
| Departure Time Zone | -- |
| Destination Same as Local Flt | -- |
| Destination Airport Code | ATL |
| Destination City | ATLANTA |
| Destination State | GA |
| Destination Country | -- |
| Specific Phase of Flight | Takeoff |
| Report sent to ICAO? | -- |
| Evacuation occurred | Yes |
| Date of most recent change to record | May 6 2003 4:43PM |
| User who most recently changed record | HAUT |
| 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 | -- |