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Fatal UPS cargo jet crash tied to long-standing structural issue
Federal investigators revealed that the November crash of a UPS-operated MD-11F freighter in Kentucky stemmed from a structural defect Boeing had flagged in similar aircraft 15 years earlier.
Crash details
The aircraft lost an engine during takeoff from Louisville International Airport, briefly becoming airborne before veering off course and slamming into an industrial zone. Three crew members and 12 ground workers died in the inferno.
NTSB findings
The National Transportation Safety Board's latest report identified fatigue cracks in the engine mounting assembly-a critical component that secures the engine to the wing. Investigators noted that repeated stress had fractured both the bearing and its housing.
Boeing had previously documented identical failures in four incidents involving three separate MD-11 aircraft. In 2011, the company issued a non-binding service letter advising operators to inspect the part every five years and referencing an optional upgraded bearing assembly.
"This component isn't cosmetic-it bears thrust and drag loads essential for flight. Boeing's assessment that its failure posed no safety risk is baffling,"
Tim Atkinson, aviation safety consultant and former air accident investigator
Boeing's history with the MD-11
The MD-11, originally developed by McDonnell Douglas, entered production in 1990. Boeing absorbed the manufacturer in 1997 and halted production in 2001, though it continues to supply parts and maintenance support.
In its 2011 service bulletin, Boeing described the defect as non-critical, a conclusion now under scrutiny following the Kentucky disaster.
Broader safety concerns
The NTSB has not yet determined the crash's root cause, with a final report pending. Boeing's internal safety protocols have faced repeated criticism, including the 737 Max's flawed flight control software linked to two fatal crashes in 2018 and 2019, and a 2024 incident where a door panel detached mid-flight on a new 737 Max.
Boeing's response
The company expressed condolences to victims' families and pledged cooperation with the NTSB's ongoing probe.
"We continue to support the investigation led by the NTSB. Our deepest condolences go out to the families who lost loved ones and our thoughts remain with all those affected."
Boeing statement
