On August 28, 1992, a Douglas DC-8-61 (registration N845AX) operated by Airborne Express Inc. was involved in an aviation accident near Morton Grove, IL. Investigators recorded the probable cause as: The fracture of the right main landing gear door actuator due to unidirectional bending fatigue, leading to component separation. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During climb, a right main landing gear door and actuator separated from the aircraft. The actuator struck a residence, penetrating the roof. The aircraft lost hydraulic pressure en route but landed safely. Metallurgical examination revealed fatigue fractures.
Incident
During the climb phase of flight, the right main landing gear door actuator and the main landing gear door separated from the aircraft. The detached door actuator collided with a residence, passing through the roof and lodging in the ceiling. No occupants of the residence were reported as injured. The flight crew returned to Chicago, during which the aircraft experienced total hydraulic pressure and fluid loss. Despite the hydraulic failure, the aircraft landed without further incident.
Examination
Post-incident examination of the separated components revealed fractures in both the operating gland housing and shaft, as well as the actuator rod end of the right main gear door. Metallurgical analysis was conducted on the gland shaft fracture. The fracture surface exhibited beach markings and other features that were largely characteristic of unidirectional bending fatigue progression. This type of fatigue indicates a progressive crack growth under cyclic loading.
Probable cause
The fracture of the right main landing gear door actuator due to unidirectional bending fatigue, leading to component separation.
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…