On the evening of January 5th local time, shortly after takeoff, an Alaska Airlines 737 MAX 9 aircraft experienced a sudden detachment of the left center rear emergency hatch from the fuselage, causing the cabin to momentarily release pressure and all oxygen masks to fall off. Subsequently, the plane made an emergency landing at Portland International Airport in Oregon. Afterwards, multiple airlines took action against their Boeing aircraft.
On the evening of the 5th local time, Alaska Airlines announced preventive measures and temporarily suspended 65 Boeing 737 MAX 9 aircraft from its fleet. Each aircraft can only resume flight after completing comprehensive maintenance and safety checks, and all inspections are expected to be completed in the coming days.
On January 7th, Beijing time, United Airlines released an update on the Boeing 737 MAX 9 fleet: Following an accident on a flight of Alaska Airlines on Friday, the company has temporarily suspended Boeing 737 MAX 9 aircraft services to carry out safety inspections required by the Federal Aviation Administration. United Airlines is the largest operator of the 737 MAX 9, and earlier stated that 33 out of 79 aircraft have undergone necessary safety checks.
In addition, Panama Airlines, Air Mexico and Türkiye Airlines announced that they would ground their Boeing 737 MAX 9 aircraft, and the number of affected aircraft was 21, 19 and 5, respectively.