Boeing issued a warning in 2011 regarding a critical part that contributed to the November 2025 crash of a UPS plane, which resulted in the deaths of 15 individuals. Though the part was found to have failed on multiple occasions in other aircraft, Boeing at that time did not classify it as a safety threat, according to the National Transportation Safety Board (NTSB).
The UPS aircraft crashed shortly after takeoff from Louisville, Kentucky, when its left engine detached from the wing, leading to a catastrophic fireball upon impact with nearby industrial buildings.
The NTSB findings indicated that Boeing had noted four prior failures of the spherical bearing used to secure the MD-11 engine to its wing. Maintenance checks had failed to catch cracks developing in these parts, raising concerns over the adequacy of inspection protocols. The last detailed examination of the engine mounts was performed in October 2021, with no further inspections scheduled for many flights.
This incident echoes a tragic crash in 1979 involving American Airlines, where a similar design flaw in the DC-10 was identified. Past lessons about engine failure related to these aircraft models have sparked discussions regarding the safety regulations and maintenance practices that have been employed over the decades.
Notably, the NTSB has not disclosed whether there have been any further failures of the spherical bearing since Boeing's 2011 warning. In the aftermath of the crash, all MD-11 aircraft were grounded as investigations proceeded.
Boeing and UPS expressed condolences to the families impacted by this tragedy, underscoring the aviation industry's continuing struggle with ensuring safety amidst complex engineering challenges. The final conclusions from the NTSB on this accident won't be available for over a year, leaving significant questions about the incident unanswered.
