The FAA on Jan. 6 grounded 171 Boeing 737 MAX 9 planes following the mid-air cabin blowout of a door plug on an eight-week old Alaska Airlines jet.
United said Monday it had "found instances that appear to relate to installation issues in the door plug -- for example, bolts that needed additional tightening."
A sightseeing plane crashes in southeast Alaska Thursday killing all nine people onboard, US police have said.
An Alaska Airlines plane declares emergency and makes priority landing at Seattle after taking off with a worker trapped in the cargo hold.
