
A critical engine part failure that led to a deadly UPS crash in Kentucky was flagged by Boeing in 2011 but dismissed as non-critical.
Story Highlights
- Boeing identified the part failure in 2011 but didn’t classify it as a safety risk.
- The crash resulted in 15 fatalities, including three pilots and 12 on the ground.
- The National Transportation Safety Board (NTSB) is investigating Boeing and UPS maintenance practices.
- All MD-11 and related DC-10 aircraft have been grounded worldwide.
Boeing’s 2011 Oversight
In 2011, Boeing issued a service letter documenting four failures of a spherical bearing race on MD-11 aircraft. Despite this, the issue was deemed non-critical, with Boeing recommending inspections but not a redesign.
This oversight is now under scrutiny as the part’s failure led to an engine detachment and subsequent crash of a UPS MD-11 cargo plane in Kentucky, resulting in significant loss of life and property damage.
Cracked part in fatal UPS crash flagged in 2011 by Boeing via CNBC:https://t.co/0BbJbY0ADN
A cracked part found on a UPS MD-11 cargo jet that crashed in November in Kentucky was reportedly flagged in a Boeing service letter more than a decade earlier.— 🌊💙 Viking Resistance 💙🌊 (@BlueCrewViking) January 15, 2026
The spherical bearing race, crucial for securing engines to the wings, was last inspected on the UPS plane in October 2021. This inspection failed to detect critical cracks that eventually led to the engine’s detachment.
The current NTSB investigation highlights potential gaps in maintenance protocols and in Boeing’s initial assessment of the part’s safety significance.
Immediate and Long-term Implications
The grounding of all MD-11 and related DC-10 aircraft has disrupted operations for major cargo carriers like UPS and FedEx. The incident has prompted a reevaluation of maintenance practices for aging aircraft fleets and may accelerate the phase-out of these older models.
The crash has also sparked legal and regulatory scrutiny of Boeing’s past safety assessments and of operators’ ongoing maintenance compliance.
The economic impact includes significant cargo delays and the cleanup of the crash site, which involves removing millions of gallons of contaminated water. This tragedy has reignited public and political debate over aviation safety standards and corporate accountability within the aerospace industry.
Stakeholder Reactions and Future Prospects
The NTSB has released a factual report confirming the part’s failure and Boeing’s prior awareness of the issue. No additional failures of the part have been documented since 2011, but the investigation continues.
Boeing, UPS, and the FAA have yet to release new statements following the NTSB’s latest findings. The final report on the crash’s cause is expected to take over a year to complete.
With the investigation ongoing, stakeholders, including Boeing and UPS, are under pressure to demonstrate their commitment to safety and transparency.
The findings may lead to policy changes that enhance oversight and maintenance practices for aging aircraft, helping prevent such tragedies in the future.
Sources:
A part that broke on a UPS plane that crashed in Kentucky failed 4 times on other planes years ago
UPS crash in Kentucky prompts scrutiny on Boeing and UPS maintenance practices








