United Airlines Finds Issues With MAX 9 Door Bolts

United Airlines has found issues with some MAX 9 door bolts during its inspections of its grounded fleet.

In its statement, United said: "Since we began preliminary inspections on Saturday, we have found instances that appear to relate to installation issues in the door plug - for example, bolts that needed additional tightening."

Inspections began after an exit door blew out from an Alaska Airlines 737 Max 9 on Friday on the flight from Portland to Ontario. The aircraft was at 16,000ft when the accident occurred and the pilots were able to successfully return the 737 to Portland.

The exit door has since been recovered (above).

United Airlines added that "installation issues" relating to door plugs would be "remedied" before the aircraft type would return to service.

United cancelled 200 flights on Monday and expected significant cancellations on Tuesday and Wednesday.

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