UPS MD-11F Preliminary Accident Report in Louisville

The NTSB presentó The preliminary report of the accident toéreo del MD-11F the UPS that took offó from Louisville to Hawái, which focuses on engine disengagement 1.

The 4 November 2025, a trálogical accidentésentencing took place at Louisville Muhammad Ali International Airport (SDF), in Louisville, Kentucky. The cargo flight 2976 de United Parcel Service (UPS), a Boeing (McDonnell-Douglas) MD-11F, crashedó shortly afterés taking off from runway 17R.

Preliminary report of the MD-11F of UPS

The Committeeé National Transportation Safety (NTSB) has issued a preliminary report detailing the initial facts and crucial findings, destaccando la separationón in flight of an engine and the subsequent caíday of the aircraft.

The flight 2976 (MD-11F), honor (Honolulu (HNL), I receivedó are authorizationsótakeoff time around 17:11. Taxiing and takeoff were uneventful until rotation.ón.

Separationóengine n in flight

• Airport surveillance videos showed that the left engine (No. 1) and his pilóThey separated from the wing shortly afterés that the aircraft rotated for takeoff.
• Separate engine caught fireó while flying over the fuselage and impactó against the ground.
• A fire startedó near to ábad connectionsón share arrowón left to the wing and persistedó until the final impact.

Impact and trajectory:

• The aircraft initially ascendedó, but not superó the 30 feet above ground level (agl) themselvesún FDR data (until 100 pies agl seún ADS-B).
• the grandfatherón clearanceó the protective fenceón, but the left main landing gear impactedó the roof of a warehouseén of UPS Supply Chain Solutions on the south edge of the airport.
• Subsequently, the grandfatherón impactó a depóstorage site and two additional buildings, including an installationópetr recycling nóleo, being largely consumed by fire.
• Witnesses reported that the rate of climb was not normal and that the aircraft lostó altitude and startedó to lean slightly to the left.

Research Findingsón y AnáComponent lysis

The investigationón with centeró ráask at the connection pointón share arrowón from engine to wing.

flight recorders

• Both the CVR (Cockpit Voice Recorder) like FDR (Flight Data Recorder) were recovered and discharged with ésuccess.
• The CVR contains the recordingócomplete n of 2 hours and 4 minutes of the accident flight.
• FDR recordedó about 450 parámeters; the recordingón terminó at 17:13:30 EAST.

pil examinationón and assembly

• The pilón left and engine were found on or near runway 17R.
• The initial examination of the rear pil assemblyón left (where it joins the wing) reveló fractures in the lugs’ (lugs) of fixationón.
• Testing at the NTSB Materials Laboratory found evidence of fatigue cracks in the rear pil assemblyón left, I addedón a áfinal overstress areas. The fatigue crack was observedó in three of the four lug fractures.
• The esf bearingérich ass tooéno fractureó circumferentially.

• To the aircraft nowó near 92,992 hours and 21,043 cycles at the time of the accident.
• An inspectionóDetailed visual of the rear pil assemblyón left was madeó for úlast time the 28 October 2021 (required each 72 months).
• The lubricación of esf bearingsérich comes trueó the 18 October 2025.
• Special detailed inspections (SDI) related to the 'lugs’ and wing support (scheduled to 29,200 and 28,000 cycles respectively) aúthere was noíhave been made, since the aircraft had notíhas reached those límites.

Immediate security actions

In response to the accident, regulatory measures were takenáask due to the nature críethics of structural failure:

• UPS inmovilizó its fleet of MD-11s 7 November 2025 as a precautionón.
• The FAA issuedó the Emergency Airworthiness Directive (AD) 2025-23-51 the 8 November 2025, prohibiting the flight of the MD-11/MD-11F until its inspectionón.
• Subsequently, Emergency AD 2025-23-53 se emitió the 14 November 2025, including both MD-11 and DC-10 series, due to its designñor the like of connectionón batteryón.

Similar events

The report isñwing the flight accident 191 de American Airlines (DC-10-10) in Chicago on 25 May 1979, where the aircraft crashedó afteréwith de la separationóengine and battery numberóleft during rotationón. This similar event highlights a concernón of sayingño histórichly associated with this family of aircraft.

The investigationóNTSB n on flight 2976 of UPS containúa ongoing to determine the precise cause of the fatigue failure and the sequence of events.

You can read the full report hereí: https://www.ntsb.gov/investigations/Pages/DCA26MA024.aspx