Submissions to Boeing's tip line for safety and quality concerns surged 500% in the first quarter of this year compared to a year ago. Boeing's manufacturing processes have been under heightened scrutiny for quality and safety issues after a Jan. 5 incident in which a Boeing 737 Max 9 operated by Alaska Airlines experienced a mid-air blowout of its plug door panel after taking off, causing the cabin to depressurize and prompting the flight to return to Oregon's Portland International Airport. A Boeing spoke ...