What to know about the blowout on a Boeing 737 Max 9 jet and why most of the planes are grounded

An emergency landing by an Alaska Airlines jetliner last Friday prompted U.S. authorities to ground most of Boeing’s 737 Max 9 aircraft, another black mark in the troubled history of the company’s Max jets

​ABC News: US An emergency landing by an Alaska Airlines jetliner last Friday prompted U.S. authorities to ground most of Boeing’s 737 Max 9 aircraft, another black mark in the troubled history of the company’s Max jets