UPS Plane Engine Fell Off, Killing 15 in Louisville Crash

UPS switched planes hours before an engine fell off its aircraft, causing a fiery crash that killed 15 people in Louisville, according to investigators.

The left engine detached from the MD-11’s left wing as the aircraft accelerated along the runway at Louisville’s Muhammad Ali International Airport in November. The plane barely cleared the airport fence before crashing into nearby businesses in a massive fireball.

All three pilots on board and 12 people on the ground were killed, with a further 23 people sustaining injuries.

The National Transportation Safety Board is convening hearings in Washington this week focusing on what led to the tragedy.

It emerged at Tuesday’s hearing that UPS had an issue with a different plane hours before the crash, and that investigators have uncovered records detailing ten prior flaws in the critical components designed to secure engines to aircraft wings. The majority of the issues were never reported to the Federal Aviation Administration.

Officials from the FAA and UPS indicated that reports they did receive regarding problems with the spherical bearings, a key focus of the investigation, may have lacked sufficient detail.

David Springer of UPS stated that Boeing’s service letters made the bearing issue "sound almost benign" and failed to mention any potential collateral damage to the lugs connecting the engine to the wing.

"I think if we would have known that at UPS, I think we would have asked a lot of different questions over the years," Springer said.

The crash

The board released over 2,000 pages of documents as it began two days of proceedings to examine the root causes of the crash.

The documents revealed that UPS switched planes hours before the crash, after a preflight inspection found a fuel leak in the first plane loaded for the trip to Hawaii.

The cargo was then loaded onto a second plane, and the flight crew shared good-natured banter with the maintenance team during its inspection about “meeting again” so soon.

This second plane promptly lost its left engine. Dramatic images the NTSB released after the crash showed the engine detaching as flames erupted on the wing.

The plane was already ablaze as it briefly got airborne, leaving behind trails of smoke.

Examining the wreckage, investigators found cracks in some of the parts that held the engine to the wing, the NTSB said. Those cracks hadn’t been caught in regular maintenance, which raised questions about the adequacy of the maintenance schedule.

The last time those key engine mount parts were examined closely was in October 2021, and the plane wasn’t due for another detailed inspection for roughly 7,000 more takeoffs and landings.

Meanwhile, all MD-11s and DC-10s, a predecessor aircraft, were grounded after the Louisville crash. NTSB investigators said Tuesday that similar part flaws were subsequently found in three other UPS planes and a DC-10.

Past problems

NTSB member Tom Chapman said investigators also found 10 different earlier examples of flaws in MD-11s, dating back more than 15 years, involving the same key part that failed in Louisville, but only four were reported to the FAA.

Chapman said all of them should have been reported. FAA officials testified Tuesday that four, spread over years, would not have been enough to demonstrate a problem trend.

Boeing determined that those flaws “would not result in a safety of flight condition,” so the plane maker didn’t require plane owners to make repairs. And the FAA never issued an airworthiness directive that would have ensured that was done. Instead, Boeing just recommended replacing the bearings with a redesigned part that was less likely to fail.

UPS officials told the NTSB that they could have done more to prevent the crash if they had only known more.

The Louisville disaster was reminiscent of a 1979 crash in Chicago involving a DC-10. The left engine also fell off in that crash, which killed 273 people and led to the worldwide grounding of 274 DC-10s.

The airliner returned to the skies because the NTSB determined that maintenance workers had damaged the plane that crashed while improperly using a forklift to reattach the engine. That meant the crash wasn’t caused by a fatal design flaw even though there had already been a number of accidents involving DC-10s.

But even at that point, the plane’s manufacturer, McDonnell Douglas, raised concerns about the spherical bearing that helps hold the engines to the wings. McDonnell Douglas later merged with Boeing.

MD-11 planes flying again

Some MD-11s, a workhorse of the cargo fleet, are now back in the air after the FAA approved Boeing's plan to replace the spherical bearing on each aircraft and increase inspections.

FedEx resumed using the planes to deliver packages on May 10, but UPS has said it plans to retire its fleet of MD-11s. Western Global also uses MD-11s but hasn’t said what it plans to do.

Some experts speculated after the crash that the MD-11s might never fly again if the repair proved to be more expensive that it was worth in these older planes.

But Boeing said it found a way to address the safety concerns simply by replacing the bearing and stepping up inspections.