The Federal Aviation Administration said that Boeing’s instructions for how airlines should check the planes were insufficient and that the company would revise them.
The cancellations were felt most acutely in Chicago, where ice and snow briefly halted all flights on Tuesday afternoon. Airports elsewhere in the Midwest and the Northeast were also affected.
Bob Sauer said that his 50-foot cedar trees had acted on the same scientific principle as an airbag, disrupting the door plug’s fall in an act known in physics as impulse.