United Airlines has 79 Max 9 aircraft and is the jet’s largest operator.
“Since we began preliminary inspections on Saturday, we have discovered areas where we believe there may be problems with the installation of door plugs, including areas where bolts may need to be tightened,” United said in a statement. “These findings will be corrected by the technical operations team to safely return the aircraft to service.”
Aircraft maker Boeing said early Monday that it had directed airlines to conduct inspections of Max 9 planes in their fleets. United had begun pre-testing operations in recent days.
There were no serious injuries in the accident aboard the Alaska Airlines flight, but initial details from the federal government indicate that the blown panel created such a force that the head restraints and part of the seat back were torn from the cabin. , the cockpit door swung open. Safety investigation. There were no passengers sitting in the two seats next to the panel.
The National Transportation Safety Board said the accident would have been worse at cruising altitude, when passengers and crew were walking around the cabin.
But the latest incident has prompted Boeing to ramp up production of its planes, including the 737 Max, while trying to eliminate years of quality defects. CEO Dave Calhoun has spent months assuring airlines, investors and financial analysts that the company is working to improve its supply chain and resolve quality issues.
Calhoun canceled this week’s internal leadership summit and plans to hold a conference call for all employees on Tuesday.
Alaska Airlines plans to inspect more than 60 737 Max 9s, but the airline did not immediately comment on whether it had found any loose bolts.
The FAA declined to comment on the United Airlines findings. Boeing did not immediately respond to CNBC’s request for comment.
The 737 Max is Boeing’s best-selling aircraft, with more than 4,000 on order. However, the more common Max 8, which is not susceptible to grounding, makes up the majority of orders.
Aviation Publications The Air Current first reported United discovered that the bolt was loose.
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