A UPS McDonnell Douglas MD-11F cargo aircraft crashed during takeoff on November 4 in Louisville, Kentucky, resulting in 15 fatalities. The incident led to the temporary grounding of MD-11 fleets by UPS and FedEx, initially based on a Boeing recommendation and subsequently mandated by the Federal Aviation Administration (FAA). Subsequent investigation by the National Transportation Safety Board (NTSB) identified fatigue cracks in a critical engine mounting component, a condition Boeing had previously noted in other MD-11 aircraft in 2011.
Incident Details
On November 4, a UPS MD-11F cargo aircraft, operating as Flight 2976, was involved in a takeoff incident at Louisville Muhammad Ali International Airport. The aircraft was bound for Honolulu, Hawaii, and was carrying 38,000 gallons of fuel. During its takeoff sequence, the aircraft's left engine ignited and detached from the wing. Investigators observed the left wing ablaze as the plane briefly lifted off the runway, reaching an altitude of no more than 30 feet, before crashing into an industrial area. The crash impacted a petroleum recycling facility and a UPS warehouse, leading to a large fire and causing damage to multiple structures.
The incident resulted in the deaths of three pilots aboard the aircraft and 12 individuals on the ground, totaling 15 fatalities. Following the crash, Louisville International Airport was temporarily closed. UPS Worldport, the company's largest package handling facility located in Louisville, resumed its Next Day Air service operations the night after the incident.
Fleet Grounding and Regulatory Response
Immediately following the crash, both UPS and FedEx announced the temporary grounding of their respective MD-11 cargo aircraft fleets. This decision was initially made after a recommendation from manufacturer Boeing, which stated the measure was taken "in an abundance of caution" while additional engineering analysis was performed. The Federal Aviation Administration (FAA) subsequently issued an emergency directive on Saturday, mandating the grounding of all MD-11 aircraft. The FAA cited "an unsafe condition likely to exist or develop in other products of the same type design" as the basis for its order.
- UPS Fleet: UPS operates approximately 26 MD-11s, which constitute about 9% of its total fleet exceeding 500 aircraft. The company had announced plans in 2023 to replace these aircraft with Boeing 767s.
- FedEx Fleet: FedEx operates 28 MD-11s, representing about 4% of its fleet of approximately 700 aircraft. FedEx had plans to retire its MD-11 fleet by fiscal year 2032, having retired 20 MD-11s in the three years prior to the incident.
- Other Operators: Western Global Airlines is also noted as an operator of MD-11 aircraft.
Both companies stated they had implemented contingency plans to mitigate potential disruptions to delivery services. However, aviation experts suggested that the grounding, particularly if extended beyond one to two weeks, could impact holiday shipping capacity, given projected increases in holiday package deliveries. Cargo redirection to alternative transportation methods, including passenger planes, trains, and trucks, was noted as a possibility.
Investigation Findings
The National Transportation Safety Board (NTSB) commenced an investigation into the crash. Preliminary findings indicated that approximately 37 seconds after the crew initiated takeoff thrust, a bell sounded in the cockpit. This sound continued for 25 seconds as pilots attempted to control the aircraft and was confirmed on the cockpit voice recorder. Former federal crash investigators suggested the bell likely signaled an engine fire, noting the incident occurred past the typical decision speed for pilots to safely abort a takeoff.
Later NTSB updates identified a specific mechanical failure as a key factor. Investigators found evidence of pre-existing metal fatigue and cracking in a 3-inch-wide metal housing around a bearing, which was integral to the mount securing the left engine to the MD-11Fâs wing. Images of the split bearing race were released. The NTSB highlighted that this specific bearing housing was the subject of a 2011 Boeing service letter. This document had alerted airlines to four previous failures of engine bearing races on three different MD-11s. At that time, Boeing had concluded that these failures "would not result in a safety of flight condition" and recommended general visual checks of the part at five-year intervals. A revised bearing assembly was also made available, though its installation was not mandatory. Aviation safety consultants noted the critical role of this structure in attaching the engine to the wing and carrying loads.
The NTSB's investigation is ongoing, and a final report detailing the probable causes of the crash and providing safety recommendations is anticipated within 18 to 24 months.
Aircraft Background
The involved MD-11F aircraft was manufactured in 1991. It began service 34 years ago as a passenger jet with Thai Airways before being transferred to UPS in 2006. The MD-11 series, originally produced by McDonnell Douglas and later by Boeing after their merger in 1997, concluded production in 2000. Its use in passenger service officially ceased in 2014. Flight records indicated the involved aircraft underwent maintenance in San Antonio for over a month until mid-October prior to the crash. The specifics of this maintenance have not been disclosed.