At United and Alaska airlines, frustration with Boeing's manufacturing problems is boiling over

“I am more than frustrated and disappointed. I am angry,” Alaska Airlines CEO Ben Minicucci said. “My demand on Boeing is, what are they going to do to improve their quality programs in-house?”

Boeing under scrutiny again after plane blowout: What's next

Alaska returned 18 of its 65 737 Max 9 aircraft to service on Saturday following inspections, but then re-grounded them hours later after learning more work may be needed.