Ups accident, Boeing had issued a warning in 2011 about the MD-11
A structural component found damaged in the plane involved in the fatal crash in Louisville had already caused problems in the past
by Mara Monti
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In 2011 Boeing warned airlines about a faulty component on the MD-11 that may have contributed to the UPS plane crash last November in which 15 people died, but at the time the manufacturer did not consider this to be a safety hazard. This is stated by the National Transportation Safety Board (NTSB), which is investigating the Louisville crash: the UPS plane crashed shortly after take-off with the left engine detaching from the wing as the plane was flying down the runway.
The NTSB stated that Boeing had documented four previous failures of a component that helps secure the MD-11's engines to the wings on three different aircraft in 2011, but the manufacturer 'determined that this would not compromise flight safety'. The NTSB did not specify whether other failures of the spherical bearing track, the part involved in the crash, had been documented since 2011. Investigators found that the component had snapped in two after the UPS crash and that the bolts securing it were cracked.
Photos released by the NTSB of the crash on 4 November show flames bursting out as the rear of the engine began to detach before flying off and overtaking the wing, which itself ignited. The three pilots of the Hawaii-bound plane were killed along with 12 other people on the ground near Louisville's Muhammad Ali International Airport.
The report published yesterday does not indicate what caused the engine to break down. The NTSB said its investigation is ongoing and includes, among other things, verification of how the BOeing letter was received by UPS, as well as correspondence between Boeing and the FAA on the subject.
The NTSB had previously stated that investigators had found cracks in some of the parts that attached the engine to the wing. However, these cracks had not been detected during the regular maintenance carried out on the aircraft, raising doubts about the adequacy of the maintenance programme. The last time those key parts of the engine mount had been closely examined was in October 2021 and the aircraft was not due for another detailed inspection before about 7,000 take-offs and landings.
