Engine brace cracked before fatal UPS plane crash, report says

A preliminary report from the US National Transportation Safety Board (NTSB) indicates a critical engine brace on the UPS cargo plane that crashed in Louisville, Kentucky, earlier this month had cracked in two places prior to the fatal incident. The bracket, designed to secure the left engine, showed signs of fatigue, contributing to the McDonnell Douglas MD-11 jet's crash shortly after takeoff on November 4. The accident tragically claimed the lives of the three crew members and 11 individuals on the ground, with 23 others sustaining injuries.

Further investigation revealed additional fatigue cracks in other parts of the pylon, the structure attaching the engine to the wing, beyond the two initial fractures identified at the crash site. The left engine detached as the aircraft accelerated down the runway, leading to a fiery crash just past the runway's end. While a comprehensive "heavy check" was performed on the plane in September, and a visual inspection by a UPS maintenance crew occurred seven days before the crash, the report notes the aircraft was not yet due for a more detailed inspection of the affected parts. The cockpit voice recorder indicated a routine preflight check, though a bell sound in the final moments remains unexplained by the current report.

In response to the preliminary findings, the US Federal Aviation Administration (FAA) has issued a temporary ban on flying MD-11s and nearly a dozen other Boeing-built jet models that share similar engine-pylon structures. Boeing, which acquired McDonnell Douglas, had already recommended that all operators ground their MD-11s while the NTSB investigation proceeded. UPS proactively grounded its MD-11 fleet, citing an abundance of caution, even before the FAA's Emergency Airworthiness Directive.

The MD-11, introduced in the 1990s, transitioned from widespread passenger service to primarily cargo operations after production ceased in 2000. These aircraft constitute nearly 10% of UPS's extensive cargo fleet. Both UPS and Boeing have affirmed their full cooperation with the NTSB's ongoing investigation, emphasizing their commitment to aviation safety as the inquiry progresses.