Airlines stocks experienced a decline on Monday after the Federal Aviation Administration (FAA) grounded all Boeing 737 Max 9 aircraft due to an emergency “incident” involving one of Alaska Airlines’ planes. The incident occurred during a scheduled flight from Portland to Ontario, California, when a mid-cabin fuselage component separated from the aircraft, causing it to make an unscheduled emergency landing. In response, Alaska Airlines grounded its fleet of 65 Boeing 737-9 aircraft for maintenance inspections. The FAA has ordered inspections for the affected 171 aircraft, with each inspection expected to take four to eight hours. As a result of these events, shares of Boeing and supplier Spirit AeroSystems declined, impacting the stock market. Alaska Airlines, Southwest Airlines, and United Airlines also experienced stock declines.