Failed Component in UPS Plane Crash was Previously Problematic, NTSB Reveals

In 2011, Boeing informed aircraft owners about a malfunctioning component that, the following year, played a part in a UPS cargo plane disaster. This accident resulted in the death of 15 individuals, yet initially, Boeing did not consider the issue to be a direct safety risk, according to the National Transportation Safety Board (NTSB).

The tragedy struck in November 2025, when a UPS aircraft crashed soon after its departure from Louisville, Kentucky. This occurred when a component within the engine attachment structure compromised the craft as it gained velocity on the runway. Unfortunately, all three pilots aboard were killed when the plane, which was en route to Hawaii, crashed into an industrial area.

According to the NTSB, as of 2011, Boeing had a record showing four former failures of the part in question that is crucial to attaching the MD-11’s engines to its wings. Despite this history, the manufacturer concluded there was no immediate flight safety risk. Notably, these aircraft were originally built by McDonnell Douglas before Boeing's acquisition of the company.

Investigations discovered fissures in the engine mounting hardware. These defects had gone unnoticed during routine maintenance checks, raising concerns about the sufficiency of the maintenance intervals. The last thorough inspection of the engine mount components was conducted in October 2021, with another detailed examination not due for approximately another 7,000 flight cycles.

Parallels Drawn to 1979 Crash in Chicago

It remains unclear precisely when the stress fractures emerged in the support components. However, this incident recalls a 1979 catastrophe in Chicago in which an American Airlines DC-10 tragically crashed after an engine separation during takeoff, causing 273 fatalities.

This prior disaster prompted a temporary global grounding of the DC-10 fleet. Yet, subsequent investigation showed that improper maintenance practices, rather than a fundamental design defect, led to the failure.

Jeff Guzzetti, a former investigator, pointed out a service advisory from McDonnell Douglas in 1980, which explicitly named the spherical bearing failure as a flight risk. This contrasts with Boeing's 2011 stance, questioning why the latter did not treat it as seriously.

FAA's Stance on 2011 Boeing Service Bulletin

The FAA refrained from mandating a response to Boeing's 2011 bulletin, which offered a recommendation rather than an obligatory repair directive.

Alan Diehl, another crash investigator, argued that the outdated bearings could still be used as replacements, despite their known tendency to fail. The NTSB continues its probe to determine the adequacy of Boeing's response to this recognized hazard.

Ongoing Investigation: Why the Engine Detached

The NTSB has yet to finalize the cause behind the engine detachment, but the focus remains on the failed bearing.

Legal actions are already in motion, with claims focusing on what both Boeing and UPS knew, and how they reacted to the identification of these issues. Attorney Brad Cosgrove emphasized that warning signs which should have prevented the Louisville disaster were evident well before the crash.

While the investigation proceeds, Boeing, UPS, and the FAA are restricted in commenting, having only shared condolences with the bereaved families.

Aging Aircraft Raises Safety Concerns

The aircraft in question, a 34-year-old MD-11, barely cleared the runway before descending into buildings and generating a significant blaze. Witnesses reported a series of explosions that followed.

Given that these models had been withdrawn from passenger service due to inefficiencies, their continued use in cargo fleets is under scrutiny, and their recent grounding underscores their potential obsolescence.