Duffy traveled to Washington and met with Boeing CEO Kelly Ortberg, along with acting FAA Administrator Chris Rocheleau, following last year's mid-air panel blowout on a new Alaska Airlines 737 MAX 9 airplane that was missing four key bolts.
Ortberg will testify April 2 before Congress.
"They've lost trust," Duffy said. "They have to take a look at how they're manufacturing. They have to look at their quality. They have to get it up to a place where the FAA and the American people and the airlines feel like they're producing incredibly safe airplanes."
Duffy noted that Boeing has new leadership.
"They are making efforts and strides to bring quality back to their aircraft," he said.