Shipping giant UPS won’t have its fleet of McDonnell Douglas MD-11s back in the air before the busy holiday season, an internal memo has revealed. The jets were grounded after a UPS MD-11 lost its left engine during takeoff in Louisville, Kentucky, on Nov. 4, and crashed in a fireball, killing 14 people. The company had hoped the process would take weeks, but it is now expected to take months. In a memo to employees, UPS Airlines president Bill Moore said, “Regarding the MD-11 fleet, Boeing’s ongoing evaluation shows that inspections and potential repairs will be more extensive than initially expected.” All carriers’ MD-11s were taken out of service for checks and repairs at the behest of the Federal Aviation Administration. According to the Associated Press, a UPS spokesperson said contingency plans would be put in place to mitigate the loss of 9 percent of its aerial fleet. They added Boeing “will take the time needed to ensure that every aircraft is safe.” Boeing merged with McDonnell Douglas in 1997 and assumed responsibility for the fleet, which has an average age of around 30 years. A Boeing spokesperson said in a statement that it was “working diligently to provide instructions and technical support to operators.”

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