(Reuters) - Alaska Air (NYSE:ALK) said on Monday its technicians found some loose hardware in the door plug area on some of its Boeing (NYSE:BA) 737 MAX 9 fleet.
U.S. regulators grounded 171 MAX 9 planes after a door plug panel blew off an Alaska Airlines-operated flight not long after taking off from a Portland, Oregon, airport on Friday, forcing pilots to scramble to land the plane safely.
"As our maintenance technicians began preparing our 737-9 MAX fleet for inspections, they accessed the area in question," Alaska Air said, referring to the door plug panel area.
"Initial reports from our technicians indicate some loose hardware was visible on some aircraft."
Earlier in the day, United Airlines said it had found loose bolts on multiple grounded MAX 9 aircraft, raising new concerns among industry experts about how its best-selling jet family is manufactured.