UPS MD 11F in Louisville - Critical pylon structural failure

By Captain Bassani - ATPL/B-727/DC-10/B-767 - Former Air Accident Inspector SIA PT. captbassani@gmail.com - Dec/2025 - https://www.personalflyer.com.br

Key takeaways from the NTSB preliminary report

Image UPS via NTSB

On November 20, 2025, the NTSB released its preliminary report on the UPS MD‑11F accident, Flight 2976, which occurred on November 4 at Louisville International Airport in Kentucky, USA. Early findings point to fatigue cracking in the aft lug of the left engine pylon, the structural element that attaches the engine to the wing, leading to separation of the engine–pylon assembly shortly after rotation, a subsequent fire in the left wing, and loss of control at very low altitude.​

Airport surveillance footage shows the left engine detaching, passing over the fuselage and falling to the ground as a fire ignites at the wing–pylon junction; the MD‑11F briefly climbed to roughly 30 feet AGL before losing lift, striking a UPS facility, crossing a storage yard and other structures, and coming to rest, with three crew members and eleven people on the ground killed and twenty‑three additional ground injuries in the impact area.

Wreckage examination and follow‑up laboratory analysis identified multiple fracture surfaces with evidence of fatigue in the aft pylon lug and in the spherical bearing on the left side, combined with overstress failure, a pattern consistent with the type of structural degradation closely monitored by agencies such as NTSB, FAA and EASA in aging fleets.​

The flight data recorder and cockpit voice recorder captured the entire short takeoff sequence and are being reviewed by dedicated NTSB groups, in line with ICAO‑recommended investigation practices for major transport accidents. Available records indicate that the crew was experienced on type, with several thousand combined hours on the MD‑11, and that the aircraft had completed required structural visual inspections in 2021, along with recent lubrication of pylon components in October 2025; special cycle‑driven inspections were not yet due at the time of the event.​

In the immediate aftermath, UPS grounded its MD‑11 fleet in coordination with Boeing, while the FAA issued emergency Airworthiness Directives for MD‑11 and DC‑10 aircraft, mandating additional inspections of engine‑mounting components before full return to service. In parallel, organizations and knowledge bases such as EASA, ICAO and SKYbrary have reiterated in their safety material the need for robust structural‑integrity programs tailored to fleet age, including fatigue monitoring at high‑cycle load points, careful management of lifed parts and continuous updates to inspection criteria.​

This tragedy highlights the need to prioritize structural integrity in complex aircraft and to maintain constant vigilance over critical components exposed to fatigue — a stark reminder of latent fragility, even in certified aircraft maintained under approved programs. The investigation into UPS Flight 2976 remains active under case number DCA26MA024, and the NTSB cautions that all preliminary findings are subject to change as metallurgical work progresses, FDR/CVR data are fully correlated, and design and maintenance programs are examined in greater depth; for professional aviation, the takeaway is clear: no aging fleet can afford to operate without solid in‑service data, strong structural‑integrity engineering and continuously updated inspection programs.​

Safe flights!

Captain Bassani

References:

• NTSB – Official investigation page for UPS Airlines Flight 2976, case DCA26MA024 (preliminary report, factual summary, damage and casualty information).​

• FAA – Emergency Airworthiness Directives and guidance on aging aircraft and structural inspection requirements affecting MD‑11/DC‑10.​

• UPS – Official corporate statement on the accident and subsequent grounding of the MD‑11 fleet.​

• Aviation press and technical outlets summarizing the NTSB preliminary report and emphasizing left‑pylon structural failure and fatigue in the aft lug.​

• General concepts on structural fatigue, accident investigation and aging‑aircraft policy from EASA, ICAO and SKYbrary, used for high‑level context only.

Wings of Knowledge Collection – International Release

In the next two months, the first three volumes of this 18-book series will be available for online purchase in

Portuguese and English, already positioned as a reference for aviation professionals and enthusiasts:

Volume 1 – Introduction to Aviation and the Role of the Pilot

Volume 2 – Human and Physiological Factors in Flight Safety

Volume 3 – The Importance of Aeronautical Knowledge in Pilot Training

More than books, these guides represent a true transformation in the training and development of aviation players — whether cadets, experienced pilots, instructors, safety managers, or enthusiasts. They provide a solid path to mastering the art and science of flying, integrating technical fundamentals, human factors, international best practices, and a forward-looking vision.

An indispensable collection for those who pursue excellence and safety in the skies.