“You look at something like that and you say ‘Wow! This is not just a Monday Morning Mistake on a production line. There is something deeper here,’ ” said Gene Doub, a former air-crash investigator for the NTSB, about the kind of failure the board had found in the case of Flight 812. Pat Duggins, a member of the Aviation Safety Institute with 28 years of experience in the industry, agreed. He told me: “It is impossible for this to have happened on just one airplane, it’s not a flash in the pan. The production regime and the maintenance-checking regimes are failing.”

– Is Boeing’s 737 an Airplane Prone to Problems? - The Daily Beast