An Alaska Airlines Boeing 737 MAX 9 had an explosive decompression shortly after takeoff on Friday, but the crew was able to land safely back at Portland International Airport. Alaska immediately grounded all 65 of its MAX 9s pending an inspection and on Saturday the FAA ordered the full U.S. fleet grounded for inspection. A plug used to fill the space that could be occupied by an optional emergency exit on the left side of the aircraft and possibly some of the structure surrounding it blew out as the plane climbed through 16,000 feet on its way from Portland to Ontario, California. The plug was in place because Alaska doesn't put enough seats in its MAX 9s to warrant the additional emergency exit.
This is a companion discussion topic for the original entry at https://www.avweb.com/aviation-news/max-suffers-explosive-decompression-no-injuries-reported