Boeing 2011 Warning May Offer Clues Into 2025 UPS Jet Crash (2)

Boeing Co. warned operators in 2011 that a key structural component found cracked in the plane involved in November’s fatal crash of a United Parcel Service Inc. freighter had failed on prior occasions.

The planemaker issued a service letter in February of that year notifying MD-11 operators of four past failures on three different planes to a part known as the spherical bearing race, safety investigators from the National Transportation Safety Board said on Wednesday. The component helps to relieve high loads and vibrations.

They included the information in a rare update released in between the agency’s preliminary and final ...