A UPS plane crash The accident, which killed 15 people last year, may have been prevented if the original inspection schedule had not been relaxed, but mechanics did not take a close look at the parts that should have been kept. Engine of flight from his wing Because federal regulators allowed Boeing to recommend it be inspected less frequently, according to testimony Wednesday.
NTSB questions also indicated that Boeing relied on outdated data when it requested an extension to the inspection schedule in 2015, and did not appear to be responsible for seven cases on other planes of the same model when major engine parts failed. For its part, the Federal Aviation Administration approved the request after a month-long review without obtaining further information.
“Safety is a shared responsibility between the airline, the manufacturer and the regulator,” said Jeff Guzzetti, an aviation safety expert. “The National Aviation Safety Board is trying to analyze the roles and responsibilities of each of these three entities.”
The two-day hearing made clear that basic safety information was not being shared among all participants, and the FAA should have been more skeptical of Boeing’s request, the former accident investigator said.
Boeing and FAA officials acknowledged that they misunderstood the risks related to the potential failure of a steel bearing and metal sheath in the engine mount before impact, and did not realize that it could break the lugs that secure the engines to the MD-11’s wings. The bearings are placed deep inside near the towers, so problems are difficult to detect without removing each motor for detailed inspections.
Boeing has extended required inspections from once every 19,900 takeoff and landing cycles, to once every 29,260 cycles, so airlines can complete more key maintenance tasks simultaneously, with less downtime. The aircraft manufacturer sought the change even after receiving reports of seven bearing defects long before the planes reached their original inspection limits. In the years after the schedule was relaxed, three more cases were discovered before the collapse.
The plane, which crashed after losing an engine while accelerating down the runway at Louisville’s Muhammad Ali International Airport, flew 21,043 cycles, so it would have been thoroughly inspected according to the original schedule. The accident killed everyone Three pilots and 12 people On the floor. Twenty-three others were injured. There was only one other crash, decades ago, that involved the loss of an engine on a similar model aircraft, but that accident was blamed on improper maintenance rather than the same defect.
Aircraft operators are not expected to deviate from federally approved maintenance schedules, said Greg Rife, who owns several aviation maintenance companies and manages a fleet of aircraft at Elevate Aviation Group.
“I wouldn’t expect UPS or any other operator to do that unless it’s specifically related to the manufacturer’s design maintenance programs,” Rife said. “Certainly everyone at UPS is dismayed by this tragic incident, but it is not up to individual airlines to reinvent their aircraft inspection program.”
NTSB Chair Jennifer Homendy said the FAA should have done more to challenge Boeing’s application in 2015, because even if regulators did not know about all the defects, they knew the planemaker had sent a service letter about them and had previously reported two of them.
“I’m confused as to why they didn’t ask for more information, do more testing, and why they only accept information that Boeing provided in the late 1980s during the certification process, basically 30 years ago,” Homendy said.
Justin Konopaski, Boeing’s director of airframe service engineering, didn’t always have answers about what his company thought at the time because the planemaker didn’t have the records. MD-11 The previous DC-10 was designed and built by McDonnell Douglas before that company merged with Boeing in 1997. However, he said Boeing should have shared details of the problems it was aware of with the FAA when it applied to extend the inspection schedule.
“I think transparency is critical in this process,” Konobaski said. “I don’t know what the engineers were thinking or how they were thinking about it, or whether they took into account those who are responsible for the failures in that discussion, I can’t say that.”
The NTSB will continue to investigate everything that may have contributed to this crash before issuing its final report likely either late this year or sometime next year.
But FedEx I resumed flying The MD-11 planes were grounded earlier this month after the Federal Aviation Administration approved Boeing’s plan to ensure their safety. The engine mounts were closely inspected after the November accident, and from now on the ball bearings will be replaced regularly, after every 4,000 take-off and landing cycles. The problems documented from 2002 to 2009 all occurred between 6,058 cycles and 13,650 cycles, Homendy said.