On May 31, 1990, a Douglas DC-9-31 (registration N8982E) was involved in an aviation accident near Atlanta, GA. Investigators recorded the probable cause as: The AC cross tie relay had failed in the closed position, preventing either generator from being brought back online. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
After takeoff, a loud clunk preceded the failure of both generators. Crew used emergency power and returned safely. Investigation found the AC cross tie relay had failed closed, preventing generator reset.
Incident Sequence
Shortly after takeoff, the flight crew heard a loud 'clunk' noise. Immediately afterward, the right generator dropped offline. The crew attempted to reset the right generator, but the attempt was unsuccessful. Subsequently, the left generator also fell offline. An attempt to reset the left generator similarly failed. The crew then selected emergency power and returned to the airport, where they performed an uneventful landing.
Examination Findings
Following the incident, an examination of the electrical system revealed that the AC cross tie relay had failed in the 'closed' position. This condition prevented either generator from being brought back online. Both generators and their associated components were examined thoroughly, and no evidence of malfunction or failure was observed in those components. The relay failure was determined to be the root cause of the inability to restore generator operation.
Probable cause
The AC cross tie relay had failed in the closed position, preventing either generator from being brought back online.
A SkyWalk Join't 3 paraglider crashed into the ground near Las Vizcachas, Chile, on September 1, 2024. The pilot and passenger sustained serious spinal…
PARAPENTE (ULTRALIVIANO NO MOTORIZADO)·2024-09-01DGAC Chile
A Cessna 172N struck electrical cables while on final approach to land at Aucó Aerodrome in Chile. The pilot was uninjured, but the aircraft sustained damage…
A Bombardier DHC-8-402 suffered a tail strike during landing at Puerto Williams on September 9, 2024. All 76 occupants were unharmed, but the aircraft…
A MYD JS-MD 3 glider veered off the runway and struck a wall at Vitacura Aerodrome on January 6, 2025. The pilot was uninjured, but the aircraft sustained…
A recreational paraglider flight in Puchuncaví, Chile, ended with the pilot sustaining serious injuries after a rapid descent and impact with a hillside on…
PARAPENTE (ULTRALIVIANO NO MOTORIZADO)·2025-03-29DGAC Chile
A Tecnam P2006T landed on its belly at an aerodrome in Poland after the crew failed to confirm landing gear deployment. The incident resulted in no injuries…