The NTSB announced that the crash of UPS Flight 2976 in Louisville in November 2025 was caused by a fatigue-related failure of a 3-inch bearing seat in the left engine pylon. Boeing had notified operators of this risk in a technical bulletin issued in 2011, but replacement of the part was not made mandatory.
Footage showed the engine separating from the wing shortly after takeoff, with the fire originating in the attachment area. Investigations revealed that the crack initiated in a design-related groove and spread around the bearing, ultimately compromising structural integrity.
It was reported that 15 people lost their lives in the accident. Following the crash, UPS grounded its MD-11 fleet, while the NTSB began reviewing maintenance practices as well as correspondence between the FAA and Boeing.
