The National Transportation Safety Board on Tuesday questioned key witnesses from Boeing, Spirit AeroSystems and the Federal Aviation Administration on the mid-air cabin panel blowout of an Alaska Airlines 737 MAX 9 door plug in January.During the start of its two-day investigative hearing, the board released 3,800 pages of factual reports and interviews from the ongoing investigation.The incident badly damaged Boeing’s reputation and led to the MAX 9 being grounded for two weeks, a ban by the FAA on expand ...