The National Transportation Safety Board is conducting a two-day hearing to review documented reports of cracks in a key component linked to the fatal November crash of a UPS MD-11 cargo jet in Kentucky that claimed 15 lives - three crew members and 12 people on the ground.
As part of its investigation, the NTSB has reported finding fatigue cracks in a support structure on the left pylon that connects the wing and the engine. The cracked element is identified as the bearing race.
In January, the NTSB disclosed that the same cracked part had been highlighted in a Boeing 2011 report which noted four prior failures of the part across three different airplanes. The agency said there were multiple reports over the prior decade of cracks in race parts on MD-11 aircraft.
The scope of the hearing extends beyond the immediate inspection findings. Participants are examining the design requirements for these components and evaluating how the Federal Aviation Administration has overseen the issue during the last two decades.
Industry operators have already taken actions tied to the crash and subsequent regulatory steps. FedEx indicated last week that it had begun resuming use of its MD-11 aircraft after the FAA lifted an order that had previously barred those planes from flying following the fatal UPS accident. Separately, UPS retired its remaining MD-11 fleet - more than two dozen cargo jets - at the end of last year.
The hearing aims to bring clarity to the chain of reports and failures tied to the bearing race and to evaluate both the component's design requirements and historical oversight. Officials and stakeholders are using the session to assemble a record of what was known about the part, how recurrent failures were reported, and how regulatory attention was applied over the prior 20 years.
Given the human toll of the accident and the recurrent technical reports noted in the investigation, the hearing is expected to concentrate on the intersection of engineering, maintenance reporting and regulatory supervision as they relate to MD-11 operations and component integrity.