The NTSB’s preliminary report reveals that a UPS MD-11F cargo plane in Louisville suffered a catastrophic engine separation due to metal fatigue, terrifying witnesses, causing injuries on the ground, and raising urgent concerns over aircraft maintenance and safety oversight.

Louisville, Kentucky—Newly released images and a preliminary report from the National Transportation Safety Board (NTSB) have shed dramatic light on the UPS McDonnell Douglas MD-11F crash that occurred on November 4, 2025, at Louisville Muhammad Ali International Airport.

The investigation reveals that a catastrophic structural failure caused the left engine and its pylon to detach from the wing moments after the aircraft lifted off the runway, horrifying airport personnel and sparking renewed scrutiny of aircraft maintenance procedures and structural integrity protocols.

According to the NTSB’s preliminary findings, the incident unfolded as the MD-11F began its climb after takeoff.

Airport surveillance footage captured the shocking moment when the left engine violently separated from the aircraft, trailing sparks and debris, and forcing the pilots to struggle to maintain control.

“It was surreal,” said James O’Leary, a ground controller who witnessed the event.

“One second the plane was climbing normally, the next the engine was gone.

Everyone on the tower just froze.

” Emergency crews immediately responded, securing the aircraft, tending to minor injuries on the ground, and beginning debris recovery operations.

Investigators quickly focused on the recovered engine pylon, examining it for signs of structural failure.

The NTSB report highlights evidence of significant metal fatigue on the lugs of the pylon’s aft mount, the critical component connecting the engine to the wing.

Fatigue cracks had developed over time, likely due to repeated stress from thousands of takeoffs, landings, and normal operational loads.

These cracks are believed to have played a central role in the catastrophic separation.

“The structural damage was subtle but fatal,” noted aviation safety expert Karen Simmons.

“It was like a ticking time bomb hidden in plain sight.”

The NTSB also released still images taken from airport surveillance video, showing the engine in midair, detached from the wing.

These visuals have gone viral online, igniting global conversations about the incident and prompting comparisons to historical aviation disasters.

One striking parallel noted by investigators is the 1979 crash of American Airlines Flight 191, where an MD-11 predecessor aircraft suffered a similar engine separation due to maintenance damage at the rear attachment point of the engine pylon.

“History seems to have a habit of repeating itself,” commented Jeff Ostroff, aviation journalist, while reviewing both accidents.

“It’s a sobering reminder of how small oversights or undetected stress can lead to catastrophic consequences.”

UPS has issued a statement confirming cooperation with the NTSB investigation while emphasizing its ongoing commitment to operational safety.

“We are reviewing the preliminary report thoroughly and working with authorities to understand all factors that contributed to this incident,” said a UPS spokesperson.

The company noted that the MD-11F fleet undergoes rigorous inspections and maintenance, but the findings underscore the critical need for continued vigilance in monitoring aircraft structures for signs of fatigue.

Eyewitnesses on the ground reported hearing a loud metallic explosion and seeing debris scattered across the runway area.

“It sounded like something ripped the sky apart,” said airport worker Angela Ruiz.

“People were screaming and running.

It was terrifying.

” While no fatalities were reported on the ground, several employees sustained minor injuries, adding to the human impact of the event.

The NTSB continues to examine potential contributing factors, including aircraft age, maintenance history, weight distribution, and environmental conditions during the flight.

Preliminary reports indicate no evidence of pilot error as a primary cause, though investigators are analyzing flight data recorders and cockpit voice recordings to construct a full sequence of events.

The agency emphasizes that these are early findings, and the final report will provide a comprehensive understanding of the incident.

The release of the surveillance images has sent shockwaves through the aviation community, prompting airlines, cargo operators, and regulatory bodies worldwide to reexamine inspection protocols for engine pylons and attachment points.

Experts have stressed that while incidents of this magnitude are rare, the potential consequences of undetected metal fatigue are severe.

“Even routine maintenance and inspections can’t always reveal hidden stress fractures,” explained Dr.

Miriam Cohen, a structural engineer specializing in aerospace.

“That’s why vigilance and redundancy in safety checks are critical.”

As the aviation industry absorbs the preliminary findings, the Louisville crash has become a case study in the risks posed by structural fatigue, highlighting both the resilience and fragility of modern aircraft.

Families of the crew have been briefed and supported, and local authorities continue to manage cleanup and airport operations.

Meanwhile, the global aviation community awaits the final NTSB report, which will likely influence policy, maintenance procedures, and aircraft design for years to come.

The UPS MD-11F crash in Louisville serves as a stark reminder that in aviation, even a single weak point can turn routine operations into a dramatic emergency, and that structural integrity remains a cornerstone of flight safety worldwide.