The Federal Aviation Administration has opened an investigation into Boeing’s role in a Friday blowout that left a refrigerator-sized hole in an Alaska Airlines 737 Max 9. The incident occurred on Alaska Airlines Flight 1282, headed from Portland to Ontario, California. The Alaska flight was operating a Boeing 737 Max 9 aircraft. The FAA grounded that model of the Max on Saturday. Investigators say a door plug positioned to fill a fuselage hole where an emergency exit can be installed blew out as the plane climbed to 16,000 feet. The plane returned safely to Portland International Airport, whe…